<PAGE>   1
                                                                    Exhibit 10.1


                 -----------------------------------------------



                             BURR-BROWN CORPORATION


                                       To


                    UNITED STATES TRUST COMPANY OF NEW YORK,
                                   as Trustee


                           ---------------------------


                                    INDENTURE


                                   Dated as of

                                February 24, 2000


                           ---------------------------



                 4 1/4% CONVERTIBLE SUBORDINATED NOTES DUE 2007



                 -----------------------------------------------
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                                TABLE OF CONTENTS

<TABLE>
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ARTICLE 1.  DEFINITIONS..................................................................................    1

         Section 1.1.   Definitions......................................................................    1

ARTICLE 2.  ISSUE, DESCRIPTION, EXECUTION, REGISTRATION AND EXCHANGE OF NOTES............................    8

         Section 2.1.   Designation Amount And Issue Of Notes............................................    8
         Section 2.2.   Form Of Notes....................................................................    8
         Section 2.3.   Date And Denomination Of Notes; Payments Of Interest.............................    9
         Section 2.4.   Execution Of Notes...............................................................   10
         Section 2.5.   Exchange And Registration Of Transfer Of Notes; Restrictions On Transfer;
                        Depositary.......................................................................   11
         Section 2.6.   Mutilated, Destroyed, Lost Or Stolen Notes.......................................   18
         Section 2.7.   Temporary Notes..................................................................   19
         Section 2.8.   Cancellation Of Notes Paid, Etc..................................................   19
         Section 2.9.   CUSIP Numbers....................................................................   19

ARTICLE 3.  REDEMPTION OF NOTES..........................................................................   20

         Section 3.1.   (a)  Initial Prohibition On Redemption...........................................   20
         Section 3.2.   Notice Of Redemptions; Selection Of Notes........................................   20
         Section 3.3.   Payment Of Notes Called For Redemption...........................................   22
         Section 3.4.   Conversion Arrangement On Call For Redemption....................................   22
         Section 3.5.   Redemption At Option Of Holders..................................................   23

ARTICLE 4.  SUBORDINATION OF NOTES.......................................................................   25

         Section 4.1.   Agreement Of Subordination.......................................................   25
         Section 4.2.   Payments To Noteholders..........................................................   26
         Section 4.3.   Subrogation Of Notes.............................................................   28
         Section 4.4.   Authorization To Effect Subordination............................................   29
         Section 4.5.   Notice To Trustee................................................................   30
         Section 4.6.   Trustee's Relation To Senior Indebtedness........................................   30
         Section 4.7.   No Impairment Of Subordination...................................................   31
         Section 4.8.   Certain Conversions Not Deemed Payment...........................................   31
         Section 4.9.   Article Applicable To Paying Agents..............................................   31
         Section 4.10.  Senior Indebtedness Entitled To Rely.............................................   32
         Section 4.11.  Reliance On Judicial Order Or Certificate Of Liquidating Agent...................   32

ARTICLE 5.  PARTICULAR COVENANTS OF THE COMPANY..........................................................   32

         Section 5.1.   Payment Of Principal, Premium And Interest.......................................   32
         Section 5.2.   Maintenance Of Office Or Agency..................................................   32
         Section 5.3.   Appointments To Fill Vacancies In Trustee's Office...............................   33
         Section 5.4.   Provisions As To Paying Agent....................................................   33
         Section 5.5.   Existence........................................................................   34
</TABLE>


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<TABLE>
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         Section 5.6.   Maintenance Of Properties........................................................   34
         Section 5.7.   Payment Of Taxes And Other Claims................................................   35
         Section 5.8.   Rule 144a Information Requirement................................................   35
         Section 5.9.   Stay, Extension And Usury Laws...................................................   35
         Section 5.10.  Compliance Certificate...........................................................   36
         Section 5.11.  Liquidated Damages Notice........................................................   36

ARTICLE 6.  NOTEHOLDERS' LISTS AND REPORTS BY THE COMPANY AND THE TRUSTEE................................   36

         Section 6.1.   Noteholders' Lists...............................................................   36
         Section 6.2.   Preservation And Disclosure Of Lists.............................................   37
         Section 6.3.   Reports By Trustee...............................................................   37
         Section 6.4.   Reports By Company...............................................................   37

ARTICLE 7.  REMEDIES OF THE TRUSTEE AND NOTEHOLDERS ON AN EVENT OF DEFAULT...............................   38

         Section 7.1.   Events Of Default................................................................   38
         Section 7.2.   Payments Of Notes On Default; Suit Therefor......................................   39
         Section 7.3.   Application Of Monies Collected By Trustee.......................................   41
         Section 7.4.   Proceedings By Noteholder........................................................   42
         Section 7.5.   Proceedings By Trustee...........................................................   43
         Section 7.6.   Remedies Cumulative And Continuing...............................................   43
         Section 7.7.   Direction Of Proceedings And Waiver Of Defaults By Majority Of Noteholders.......   43
         Section 7.8.   Notice Of Defaults...............................................................   44
         Section 7.9.   Undertaking To Pay Costs.........................................................   44

ARTICLE 8.  THE TRUSTEE..................................................................................   44

         Section 8.1.   Duties And Responsibilities Of Trustee...........................................   44
         Section 8.2.   Reliance On Documents, Opinions, Etc.............................................   46
         Section 8.3.   No Responsibility For Recitals, Etc..............................................   46
         Section 8.4.   Trustee, Paying Agents, Conversion Agents Or Registrar May Own Notes.............   47
         Section 8.5.   Monies To Be Held In Trust.......................................................   47
         Section 8.6.   Compensation And Expenses Of Trustee.............................................   47
         Section 8.7.   Officers' Certificate As Evidence................................................   47
         Section 8.8.   Conflicting Interests Of Trustee.................................................   48
         Section 8.9.   Eligibility Of Trustee...........................................................   48
         Section 8.10.  Resignation or Removal Of Trustee................................................   48
         Section 8.11.  Acceptance By Successor Trustee..................................................   49
         Section 8.12.  Succession By Merger, Etc........................................................   50
         Section 8.13.  Preferential Collection Of Claims................................................   50
         Section 8.14.  Trustee's Application For Instructions From The Company..........................   50

ARTICLE 9.  THE NOTEHOLDERS..............................................................................   51

         Section 9.1.   Action By Noteholders............................................................   51
         Section 9.2.   Proof Of Execution By Noteholders................................................   51
</TABLE>


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<TABLE>
<CAPTION>
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         Section 9.3.   Who Are Deemed Absolute Owners...................................................   51
         Section 9.4.   Company-Owned Notes Disregarded..................................................   52
         Section 9.5.   Revocation Of Consents; Future Holders Bound.....................................   52

ARTICLE 10. MEETINGS OF NOTEHOLDERS......................................................................   52

         Section 10.1.  Purpose Of Meetings..............................................................   52
         Section 10.2.  Call Of Meetings By Trustee......................................................   53
         Section 10.3.  Call Of Meetings By Company Or Noteholders.......................................   53
         Section 10.4.  Qualifications For Voting........................................................   53
         Section 10.5.  Regulations......................................................................   53
         Section 10.6.  Voting...........................................................................   54
         Section 10.7.  No Delay Of Rights By Meeting....................................................   54

ARTICLE 11. SUPPLEMENTAL INDENTURES......................................................................   55

         Section 11.1.  Supplemental Indentures Without Consent Of Noteholders...........................   55
         Section 11.2.  Supplemental Indenture With Consent Of Noteholders...............................   56
         Section 11.3.  Effect Of Supplemental Indenture.................................................   57
         Section 11.4.  Notation On Notes................................................................   57
         Section 11.5.  Evidence Of Compliance Of Supplemental Indenture To Be Furnished To Trustee......   57

ARTICLE 12. CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE............................................   58

         Section 12.1.  Company May Consolidate, Etc.On Certain Terms....................................   58
         Section 12.2.  Successor Corporation To Be Substituted..........................................   58
         Section 12.3.  Opinion Of Counsel To Be Given Trustee...........................................   59

ARTICLE 13. SATISFACTION AND DISCHARGE OF INDENTURE......................................................   59

         Section 13.1.  Discharge Of Indenture...........................................................   59
         Section 13.2.  Deposited Monies To Be Held In Trust By Trustee..................................   59
         Section 13.3.  Paying Agent To Repay Monies Held................................................   60
         Section 13.4.  Return Of Unclaimed Monies.......................................................   60
         Section 13.5.  Reinstatement....................................................................   60

ARTICLE 14. IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS AND DIRECTORS..............................   60

         Section 14.1.  Indenture And Notes Solely Corporate Obligations.................................   60

ARTICLE 15. CONVERSION OF NOTES..........................................................................   61

         Section 15.1.  Right To Convert.................................................................   61
         Section 15.2.  Exercise Of Conversion Privilege; Issuance Of Common Stock On Conversion;
                        No Adjustment For Interest Or Dividends..........................................   61
         Section 15.3.  Cash Payments In Lieu Of Fractional Shares.......................................   63
         Section 15.4.  Conversion Price.................................................................   63
         Section 15.5.  Adjustment Of Conversion Price...................................................   63
         Section 15.6.  Effect Of Reclassification, Consolidation, Merger Or Sale........................   72
         Section 15.7.  Taxes On Shares Issued...........................................................   73
</TABLE>


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<TABLE>
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         Section 15.8.  Reservation Of Shares; Shares To Be Fully Paid; Compliance With
                        Governmental Requirements; Listing Of Common Stock...............................   73
         Section 15.9.  Responsibility Of Trustee........................................................   74
         Section 15.10. Notice To Holders Prior To Certain Actions.......................................   74

ARTICLE 16. MISCELLANEOUS PROVISIONS.....................................................................   75

         Section 16.1.  Provisions Binding On Company's Successors.......................................   75
         Section 16.2.  Official Acts By Successor Corporation...........................................   75
         Section 16.3.  Addresses For Notices, Etc.......................................................   75
         Section 16.4.  Governing Law....................................................................   76
         Section 16.5.  Evidence Of Compliance With Conditions Precedent; Certificates To Trustee........   76
         Section 16.6.  Legal Holidays...................................................................   76
         Section 16.7.  Trust Indenture Act..............................................................   77
         Section 16.8.  No Security Interest Created.....................................................   77
         Section 16.9.  Benefits Of Indenture............................................................   77
         Section 16.10. Table Of Contents, Headings, Etc.................................................   77
         Section 16.11. Authenticating Agent.............................................................   77
         Section 16.12. Execution In Counterparts........................................................   78
         Section 16.13. Severability.....................................................................   78

</TABLE>




                                       iv
<PAGE>   6
Reconciliation and Tie Between the Trust Indenture Act of 1939 and Indenture,
dated as of February __, 2000, between Burr-Brown Corporation and United States
Trust Company of New York, as Trustee.

<TABLE>
<CAPTION>
TRUST INDENTURE ACT SECTION                                    INDENTURE SECTION

<S>                                                        <C>
Section 310(a)(1)............................................................8.9
         (a)(2)..............................................................8.9
         (a)(3).............................................................N.A.
         (a)(4).............................................................N.A.
         (a)(5)..............................................................8.9
         (b)................................................8.8; 8.9; 8.10; 8.11
Section 311(a)..............................................................8.13
         (b)................................................................8.13
         (c)................................................................N.A.
Section 312(a).......................................................6.1; 6.2(a)
         (b)..............................................................6.2(b)
         (c)..............................................................6.2(c)
Section 313(a)............................................................6.3(a)
         (b)..............................................................6.3(a)
         (c)..............................................................6.3(a)
         (d)..............................................................6.3(b)
Section 314(a).........................................................5.10, 6.4
         (b)................................................................N.A.
         (c)(1).............................................................16.5
         (c)(2).............................................................16.5
         (c)(3).............................................................N.A.
         (d)................................................................N.A.
         (e)................................................................16.5
         Section 315(a)......................................................8.1
         (b).................................................................7.8
         (c).................................................................8.1
         (d).................................................................8.1
         (d)(1)...........................................................8.1(a)
         (d)(2)...........................................................8.1(b)
         (d)(3)...........................................................8.1(c)
         (e).................................................................7.9
Section 316(a)..........................................................7.7, 9.4
         (a)(1)(A)...........................................................7.7
         (a)(1)(B)...........................................................7.7
         (a)(2).............................................................N.A.
         (b).................................................................7.4
         (c).................................................................9.1
Section 317(a)(1).......................................................7.2, 7.5
         (a)(2).........................................................7.2, 7.5
         (b).................................................................5.4
Section 318(a)..............................................................16.7
</TABLE>

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*        Note: This reconciliation and tie shall not, for any purpose, be deemed
         to be a part of the Indenture.
<PAGE>   7
**       Note: N.A. means Not Applicable.
<PAGE>   8
                                    INDENTURE

                  INDENTURE, dated as of February 24, 2000, between Burr-Brown
Corporation, a Delaware corporation (hereinafter called the "Company"), having
its principal office at 6730 South Tucson Boulevard, Tucson, Arizona 85706, and
United States Trust Company of New York, a New York corporation, as trustee
hereunder (hereinafter called the "Trustee"), having its principal corporate
office at 114 W. 47th Street, New York, New York 10036-1532.

                              W I T N E S S E T H:

                  WHEREAS, for its lawful corporate purposes, the Company has
duly authorized the issue of its 4 1/4% Convertible Subordinated Notes due 2007
(hereinafter called the "Notes"), in an aggregate principal amount not to exceed
$287,500,000 and, to provide the terms and conditions upon which the Notes are
to be authenticated, issued and delivered, the Company has duly authorized the
execution and delivery of this Indenture; and

                  WHEREAS, the Notes, the certificate of authentication to be
borne by the Notes, a form of assignment, a form of option to elect repayment
upon a Fundamental Change, and a form of conversion notice to be borne by the
Notes are to be substantially in the forms hereinafter provided for; and

                  WHEREAS, all acts and things necessary to make the Notes, when
executed by the Company and authenticated and delivered by the Trustee or a duly
authorized authenticating agent, as in this Indenture provided, the valid,
binding and legal obligations of the Company, and to constitute this Indenture a
valid agreement according to its terms, have been done and performed, and the
execution of this Indenture and the issue hereunder of the Notes have in all
respects been duly authorized.

                  NOW, THEREFORE, THIS INDENTURE WITNESSETH:

                  That in order to declare the terms and conditions upon which
the Notes are, and are to be, authenticated, issued and delivered, and in
consideration of the premises and of the purchase and acceptance of the Notes by
the holders thereof, the Company covenants and agrees with the Trustee for the
equal and proportionate benefit of the respective holders from time to time of
the Notes (except as otherwise provided below), as follows:

                                   ARTICLE 1.

                                   DEFINITIONS

                  Section 1.1. Definitions. The terms defined in this Section
1.1 (except as herein otherwise expressly provided or unless the context
otherwise requires) for all purposes of this Indenture and of any indenture
supplemental hereto shall have the respective meanings specified in this Section
1.1. All other terms used in this Indenture that are defined in the Trust
Indenture Act or which are by reference therein defined in the Securities Act
(except as herein otherwise expressly provided or unless the context otherwise
requires) shall have the meanings assigned to such terms in said Trust Indenture
Act and in said Securities Act as in force at the date of the execution of this
Indenture. The words "herein", "hereof", "hereunder", and words of
<PAGE>   9
similar import refer to this Indenture as a whole and not to any particular
Article, Section or other Subdivision. The terms defined in this Article include
the plural as well as the singular.

                  "Affiliate" of any specified Person means any other Person
directly or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person. For the purposes of this definition,
"control", when used with respect to any specified Person means the power to
direct or cause the direction of the management and policies of such Person,
directly or indirectly, whether through the ownership of voting securities, by
contract or otherwise, and the terms "controlling" and "controlled" have
meanings correlative to the foregoing.

                  "Board Of Directors" means the Board of Directors of the
Company or a committee of such Board duly authorized to act for it hereunder.

                  "Business Day" means each Monday, Tuesday, Wednesday, Thursday
and Friday which is not a day on which the banking institutions in The City of
New York or the city in which the Corporate Trust Office is located are
authorized or obligated by law or executive order to close or be closed.

                  "Closing Price" has the meaning specified in Section
15.5(h)(1).

                  "Commission" means the Securities and Exchange Commission, as
from time to time constituted, created under the Exchange Act, or, if at any
time after the execution of this Indenture such Commission is not existing and
performing the duties now assigned to it under the Trust Indenture Act, then the
body performing such duties at such time.

                  "Common Stock" means any stock of any class of the Company
which has no preference in respect of dividends or of amounts payable in the
event of any voluntary or involuntary liquidation, dissolution or winding up of
the Company and which is not subject to redemption by the Company. Subject to
the provisions of Section 15.6, however, shares issuable on conversion of Notes
shall include only shares of the class designated as common stock of the Company
at the date of this Indenture (namely, the Common Stock, par value $.01 per
share) or shares of any class or classes resulting from any reclassification or
reclassifications thereof and which have no preference in respect of dividends
or of amounts payable in the event of any voluntary or involuntary liquidation,
dissolution or winding up of the Company and which are not subject to redemption
by the Company; provided, however, that if at any time there shall be more than
one such resulting class, the shares of each such class then so issuable shall
be substantially in the proportion which the total number of shares of such
class resulting from all such reclassifications bears to the total number of
shares of all such classes resulting from all such reclassifications.

                  "Company" means the corporation named as the "Company" in the
first paragraph of this Indenture, and, subject to the provisions of Article
Twelve, shall include its successors and assigns.

                  "Company Notice" has the meaning specified in Section 3.5(b).

                  "Conversion Price" has the meaning specified in Section 15.4.



                                       2
<PAGE>   10
                  "Corporate Trust Office" or other similar term, means the
designated office of the Trustee at which at any particular time its corporate
trust business shall be administered, which office is, at the date as of which
this Indenture is dated, located at 114 W. 47th Street, New York, New York
10036, Attention: Corporate Trust Department (Burr-Brown Corporation, 4 1/4%
Convertible Subordinated Notes due 2007 ).

                  "Credit Agreement" means that certain Loan Agreement between
the Company and Wells Fargo Bank, N.A. in the aggregate amount of $10,000,000,
dated January 31, 1996, as amended on November 15, 1996, December 21, 1997,
December 2, 1998, May 28, 1999 and February 8, 2000 for establishing a line of
credit (including all deferrals, renewals, extensions or refundings of, or
amendments, modifications or supplements to, the foregoing).

                  "Custodian" means United States Trust Company of New York, as
custodian with respect to the Notes in global form, or any successor entity
thereto.

                  "Default" means any event that is, or after notice or passage
of time, or both, would be, an Event of Default.

                  "Defaulted Interest" has the meaning specified in Section 2.3.

                  "Depositary" means, with respect to the Notes issuable or
issued in whole or in part in global form, the Person specified in Section
2.5(d) as the Depositary with respect to such Notes, until a successor shall
have been appointed and become such pursuant to the applicable provisions of
this Indenture, and thereafter, "Depositary" shall mean or include such
successor.

                  "Designated Senior Indebtedness" means Senior Indebtedness
under the Credit Agreement and the Company's obligations under any other
particular Senior Indebtedness in which the instrument creating or evidencing
the same or the assumption or guarantee thereof (or related agreements or
documents to which the Company is a party) expressly provides that such Senior
Indebtedness shall be "Designated Senior Indebtedness" for purposes of this
Indenture; provided that such instrument, agreement or other document may place
limitations and conditions on the right of such Senior Indebtedness to exercise
the rights of Designated Senior Indebtedness. If any payment made to any holder
of any Designated Senior Indebtedness or its Representative with respect to such
Designated Senior Indebtedness is rescinded or must otherwise be returned by
such holder or Representative upon the insolvency, bankruptcy or reorganization
of the Company or otherwise, the reinstated Indebtedness of the Company arising
as a result of such rescission or return shall constitute Designated Senior
Indebtedness effective as of the date of such rescission or return.

                  "Event Of Default" means any event specified in Section
7.1(a), (b), (c), (d) or (e).

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder, as in effect from
time to time.

                  "Fundamental Change" means the occurrence of any transaction
or event in connection with which all or substantially all of the Common Stock
shall be exchanged for, converted into, acquired for or constitute solely the
right to receive consideration (whether by


                                       3
<PAGE>   11
means of an exchange offer, liquidation, tender offer, consolidation, merger,
combination, reclassification, recapitalization or otherwise) which is not all
or substantially all common stock listed (or, upon consummation of or
immediately following such transaction or event, which will be listed) on a
United States national securities exchange or approved for quotation on the
Nasdaq National Market or any similar United States system of automated
dissemination of quotations of securities prices.

                  "Global Note" has the meaning set forth in Section 2.5(b).

                  "Indebtedness" means, with respect to any Person, and without
duplication, (a) all indebtedness, obligations and other liabilities (contingent
or otherwise) of such Person for borrowed money (including obligations of the
Company in respect of overdrafts, foreign exchange contracts, currency exchange
agreements, interest rate protection agreements, and any loans or advances from
banks, whether or not evidenced by notes or similar instruments) or evidenced by
bonds, debentures, notes or similar instruments (whether or not the recourse of
the lender is to the whole of the assets of such Person or to only a portion
thereof), other than any account payable or other accrued current liability or
obligation incurred in the ordinary course of business in connection with the
obtaining of materials or services; (b) all reimbursement obligations and other
liabilities (contingent or otherwise) of such Person with respect to letters of
credit, bank guarantees or bankers' acceptances; (c) all obligations and
liabilities (contingent or otherwise) in respect of leases of such Person
required, in conformity with generally accepted accounting principles, to be
accounted for as capitalized lease obligations on the balance sheet of such
Person and all obligations and other liabilities (contingent or otherwise) under
any lease or related document (including a purchase agreement) in connection
with the lease of real property which provides that such Person is contractually
obligated to purchase or cause a third party to purchase the leased property and
thereby guarantee a minimum residual value of the leased property to the lessor
and the obligations of such Person under such lease or related document to
purchase or to cause a third party to purchase such leased property; (d) all
obligations of such Person (contingent or otherwise) with respect to an interest
rate or other swap, cap or collar agreement or other similar instrument or
agreement or foreign currency hedge, exchange, purchase or similar instrument or
agreement; (e) all direct or indirect guaranties or similar agreements by such
Person in respect of, and obligations or liabilities (contingent or otherwise)
of such Person to purchase or otherwise acquire or otherwise assure a creditor
against loss in respect of, indebtedness, obligations or liabilities of another
Person of the kind described in clauses (a) through (d); (f) any indebtedness or
other obligations described in clauses (a) through (e) secured by any mortgage,
pledge, lien or other encumbrance existing on property which is owned or held by
such Person, regardless of whether the indebtedness or other obligation secured
thereby shall have been assumed by such Person; and (g) any and all deferrals,
renewals, extensions and refundings of, or amendments, modifications or
supplements to, any indebtedness, obligation or liability of the kind described
in clauses (a) through (f).

                  "Indenture" means this instrument as originally executed or,
if amended or supplemented as herein provided, as so amended or supplemented.

                  "Initial Purchasers" means Morgan Stanley & Co. Incorporated,
Salomon Smith Barney Inc. and FleetBoston Robertson Stephens Inc.



                                       4
<PAGE>   12
                  "Institutional Accredited Investor" means an institutional
"accredited investor" within the meaning of Rule 501(a)(1), (2), (3) or (7)
under the Securities Act.

                  "Liquidated Damages" has the meaning specified for "Liquidated
Damages Amount" in Section 2(e) of the Registration Rights Agreement.

                  "Non-Payment Default" has the meaning specified in Section
4.2(ii).

                  "Note" or "Notes" means any Note or Notes, as the case may be,
authenticated and delivered under this Indenture, including the Global Note.

                  "Note Register" has the meaning specified in Section 2.5(a).

                  "Note Registrar" has the meaning specified in Section 2.5(a).

                  "Noteholder" or "Holder" as applied to any Note, or other
similar terms (but excluding the term "beneficial holder"), means any Person in
whose name at the time a particular Note is registered on the Note registrar's
books.

                  "Notice Date" has the meaning specified in Section 3.1(b).

                  "Officers' Certificate", when used with respect to the
Company, means a certificate signed by both (a) the Chairman of the Board, the
Chief Executive Officer, the President or any Vice President (whether or not
designated by a number or numbers or word or words added before or after the
title "Vice President") and (b) the Treasurer or any Assistant Treasurer, the
Controller or any Assistant Controller, or the Secretary or any Assistant
Secretary of the Company.

                  "Opinion Of Counsel" means an opinion in writing signed by
legal counsel, who may be an employee of or counsel to the Company, or other
counsel reasonably acceptable to the Trustee.

                  "Optional Redemption" has the meaning specified in Section
3.1(b).

                  "Outstanding", when used with reference to Notes and subject
to the provisions of Section 9.4, means, as of any particular time, all Notes
authenticated and delivered by the Trustee under this Indenture, except:

                  (a) Notes theretofore canceled by the Trustee or delivered to
         the Trustee for cancellation;

                  (b) Notes, or portions thereof, (i) for the redemption of
         which monies in the necessary amount shall have been deposited in trust
         with the Trustee or with any paying agent (other than the Company) or
         (ii) which shall have been otherwise defeased in accordance with
         Article Thirteen;


                  (c) Notes in lieu of which, or in substitution for which,
         other Notes shall have been authenticated and delivered pursuant to the
         terms of Section 2.6; and


                                       5
<PAGE>   13
                  (d) Notes converted into Common Stock pursuant to Article
         Fifteen and Notes deemed not outstanding pursuant to Article Three.

                  "Payment Blockage Notice" has the meaning specified in Section
4.2(ii).

                  "Person" means a corporation, an association, a partnership, a
limited liability company, an individual, a joint venture, a joint stock
company, a trust, an unincorporated organization or a government or an agency or
a political subdivision thereof.

                  "Portal Market" means The Portal Market operated by the
National Association of Securities Dealers, Inc. or any successor thereto.

                  "Predecessor Note" of any particular Note means every previous
Note evidencing all or a portion of the same debt as that evidenced by such
particular Note, and, for the purposes of this definition, any Note
authenticated and delivered under Section 2.6 in lieu of a lost, destroyed or
stolen Note shall be deemed to evidence the same debt as the lost, destroyed or
stolen Note that it replaces.

                  "QIB" means a "qualified institutional buyer" as defined in
Rule 144A.

                  "Registration Rights Agreement" means that certain
Registration Rights Agreement, dated as of February 24, 2000, among the Company
and the Initial Purchasers, as amended from time to time in accordance with its
terms.

                  "Representative" means (a) the indenture trustee or other
trustee, agent or representative for holders of Senior Indebtedness or (b) with
respect to any Senior Indebtedness that does not have any such trustee, agent or
other representative, (i) in the case of such Senior Indebtedness issued
pursuant to an agreement providing for voting arrangements as among the holders
or owners of such Senior Indebtedness, any holder or owner of such Senior
Indebtedness acting with the consent of the required persons necessary to bind
such holders or owners of such Senior Indebtedness and (ii) in the case of all
other such Senior Indebtedness, the holder or owner of such Senior Indebtedness.

                  "Responsible Officer", when used with respect to the Trustee,
means an officer of the Trustee in the Corporate Trust Office assigned and duly
authorized by the Trustee to administer this Indenture.

                  "Restricted Securities" has the meaning specified in Section
2.5(d).

                  "Rule 144A" means Rule 144A as promulgated under the
Securities Act.

                  "Securities Act" means the Securities Act of 1933, as amended,
and the rules and regulations promulgated thereunder, as in effect from time to
time.

                  "Senior Indebtedness" means the principal of, premium, if any,
interest (including all interest accruing subsequent to the commencement of any
bankruptcy or similar proceeding, whether or not a claim for post-petition
interest is allowable as a claim in any such proceeding) and rent payable on or
in connection with, and all fees, costs, expenses and other amounts


                                       6
<PAGE>   14
accrued or due on or in connection with, Indebtedness of the Company, whether
outstanding on the date of this Indenture or thereafter created, incurred,
assumed, guaranteed or in effect guaranteed by the Company (including all
deferrals, renewals, extensions or refundings of, or amendments, modifications
or supplements to, the foregoing), unless in the case of any particular
Indebtedness the instrument creating or evidencing the same or the assumption or
guarantee thereof expressly provides that such Indebtedness shall not be senior
in right of payment to the Notes or expressly provides that such Indebtedness is
"Pari Passu" or "junior" to the Notes. Notwithstanding the foregoing, the term
Senior Indebtedness shall not include any Indebtedness of the Company to any
subsidiary of the Company, a majority of the voting stock of which is owned,
directly or indirectly, by the Company. If any payment made to any holder of any
Senior Indebtedness or its Representative with respect to such Senior
Indebtedness is rescinded or must otherwise be returned by such holder or
Representative upon the insolvency, bankruptcy or reorganization of the Company
or otherwise, the reinstated Indebtedness of the Company arising as a result of
such rescission or return shall constitute Senior Indebtedness effective as of
the date of such rescission or return.

                  "Significant Subsidiary" means, as of any date of
determination, a Subsidiary of the Company, if as of such date of determination
either (a) the assets of such subsidiary equal 10% or more of the Company's
total consolidated assets or (b) the total revenue of which represented 10% or
more of the Company's consolidated total revenue for the most recently completed
fiscal year.

                  "Subsidiary" means, with respect to any Person, (i) any
corporation, association or other business entity of which more than 50% of the
total voting power of shares of capital stock or other equity interest entitled
(without regard to the occurrence of any contingency) to vote in the election of
directors, managers or trustees thereof is at the time owned or controlled,
directly or indirectly, by such Person or one or more of the other subsidiaries
of that Person (or a combination thereof) and (ii) any partnership (a) the sole
general partner or managing general partner of which is such Person or a
subsidiary of such Person or (b) the only general partners of which are such
Person or one or more subsidiaries of such Person (or any combination thereof).

                  "Trading Day" has the meaning specified in Section 15.5(h)(5).

                  "Trigger Event" has the meaning specified in Section 15.5(d).

                  "Trust Indenture Act" means the Trust Indenture Act of 1939
(15 U.S. Code Sections 77aaa-77bbb), as amended, as it was in force at the
date of this Indenture, except as provided in Sections 11.3 and 15.6; provided,
however, that, in the event the Trust Indenture Act of 1939 is amended after the
date hereof, the term "Trust Indenture Act" shall mean, to the extent required
by such amendment, the Trust Indenture Act of 1939 as so amended.

                  "Trustee" means United States Trust Company of New York until
a successor replaces it in accordance with the applicable provisions of this
Indenture and thereafter means the successor that may be appointed pursuant to
Article 8 hereof and any corporation resulting from or surviving any
consolidation or merger to which it or its successors may be a party and any
successor trustee at the time serving as successor trustee hereunder.



                                       7
<PAGE>   15
                  The definitions of certain other terms are as specified in
Sections 2.5 and 3.5 and Article Fifteen.

                                   ARTICLE 2.

                         ISSUE, DESCRIPTION, EXECUTION,
                       REGISTRATION AND EXCHANGE OF NOTES

                  Section 2.1. Designation Amount And Issue Of Notes. The Notes
shall be designated as "4 1/4% Convertible Subordinated Notes due 2007." Notes
not to exceed the aggregate principal amount of $287,500,000 (except pursuant to
Sections 2.5, 2.6, 3.3, 3.5 and 15.2 hereof) upon the execution of this
Indenture, or from time to time thereafter, may be executed by the Company and
delivered to the Trustee for authentication, and the Trustee shall thereupon
authenticate and deliver said Notes to or upon the written order of the Company,
signed by (a) its Chairman of the Board, Chief Executive Officer, President or
any Vice President (whether or not designated by a number or numbers or word or
words added before or after the title "Vice President") and (b) its Treasurer or
any Assistant Treasurer, its Controller or any Assistant Controller or its
Secretary or any Assistant Secretary, without any further action by the Company
hereunder.

                  Section 2.2. Form Of Notes. The Notes and the Trustee's
certificate of authentication to be borne by such Notes shall be substantially
in the form set forth in Exhibit A, which is incorporated in and made a part of
this Indenture.

                  Any of the Notes may have such letters, numbers or other marks
of identification and such notations, legends and endorsements as the officers
executing the same may approve (execution thereof to be conclusive evidence of
such approval) and as are not inconsistent with the provisions of this
Indenture, or as may be required to comply with any law or with any rule or
regulation made pursuant thereto or with any rule or regulation of any
securities exchange or automated quotation system on which the Notes may be
listed, or to conform to usage.

                  Any Global Note shall represent such of the outstanding Notes
as shall be specified therein and shall provide that it shall represent the
aggregate amount of outstanding Notes from time to time endorsed thereon and
that the aggregate amount of outstanding Notes represented thereby may from time
to time be increased or reduced to reflect transfers or exchanges permitted
hereby. Any endorsement of a Global Note to reflect the amount of any increase
or decrease in the amount of outstanding Notes represented thereby shall be made
by the Trustee or the Custodian, at the direction of the Trustee, in such manner
and upon instructions given by the holder of such Notes in accordance with this
Indenture. Payment of principal of and interest and premium, if any, on any
Global Note shall be made to the holder of such Note.

                  The terms and provisions contained in the form of Note
attached as Exhibit A hereto shall constitute, and are hereby expressly made, a
part of this Indenture and, to the extent applicable, the Company and the
Trustee, by their execution and delivery of this Indenture, expressly agree to
such terms and provisions and to be bound thereby.



                                       8
<PAGE>   16
                  Section 2.3. Date And Denomination Of Notes; Payments Of
Interest. The Notes shall be issuable in registered form without coupons in
denominations of $1,000 principal amount and integral multiples thereof. Every
Note shall be dated the date of its authentication and shall bear interest from
the applicable date in each case as specified on the face of the form of Note
attached as Exhibit A hereto. Interest on the Notes shall be computed on the
basis of a 360-day year comprised of twelve (12) 30-day months.

                  The Person in whose name any Note (or its Predecessor Note) is
registered on the Note register at the close of business on any record date with
respect to any interest payment date shall be entitled to receive the interest
payable on such interest payment date, except (i) that the interest payable upon
redemption (unless the date of redemption is an interest payment date) will be
payable to the Person to whom principal is payable and (ii) as set forth in the
next succeeding sentence. In the case of any Note (or portion thereof) that is
converted into Common Stock during the period from (but excluding) a record date
to (but excluding) the next succeeding interest payment date either (x) if such
Note (or portion thereof) has been called for redemption on a redemption date
which occurs during such period, or is to be redeemed in connection with a
Fundamental Change on a Repurchase Date (as defined in Section 3.5) that occurs
during such period, the Company shall not be required to pay interest on such
interest payment date in respect of any such Note (or portion thereof) except to
the extent required to be paid upon redemption of such Note or portion thereof
pursuant to Section 3.3 or 3.5 hereof or (y) if such Note (or portion thereof)
has not been called for redemption on a redemption date that occurs during such
period and is not to be redeemed in connection with a Fundamental Change on a
Repurchase Date that occurs during such period, such Note (or portion thereof)
that is submitted for conversion during such period shall be accompanied by
funds equal to the interest payable on such succeeding interest payment date on
the principal amount so converted, as provided in the penultimate paragraph of
Section 15.2 hereof. Interest shall be payable at the office of the Company
maintained by the Company for such purposes in the Borough of Manhattan, City of
New York, which shall initially be an office or agency of the Trustee and may,
as the Company shall specify to the paying agent in writing by each record date,
be paid either (i) by check mailed to the address of the Person entitled thereto
as it appears in the Note register (provided that the holder of Notes with an
aggregate principal amount in excess of $2,000,000 shall, at the written
election of such holder, be paid by wire transfer in immediately available
funds) or (ii) by transfer to an account maintained by such Person located in
the United States; provided, however, that payments to the Depositary will be
made by wire transfer of immediately available funds to the account of the
Depositary or its nominee. The term "record date" with respect to any interest
payment date shall mean the February 1 or August 1 preceding the relevant
February 15 or August 15, respectively.

                  Any interest on any Note which is payable, but is not
punctually paid or duly provided for, on any February 15 or August 15 (herein
called "Defaulted Interest") shall forthwith cease to be payable to the
Noteholder on the relevant record date by virtue of his having been such
Noteholder, and such Defaulted Interest shall be paid by the Company, at its
election in each case, as provided in clause (1) or (2) below:

                           (1) The Company may elect to make payment of any
Defaulted Interest to the Persons in whose names the Notes (or their respective
Predecessor Notes) are registered at the close of business on a special record
date for the payment of such Defaulted


                                       9
<PAGE>   17
Interest, which shall be fixed in the following manner. The Company shall notify
the Trustee in writing of the amount of Defaulted Interest to be paid on each
Note and the date of the payment (which shall be not less than twenty-five (25)
days after the receipt by the Trustee of such notice, unless the Trustee shall
consent to an earlier date), and at the same time the Company shall deposit with
the Trustee an amount of money equal to the aggregate amount to be paid in
respect of such Defaulted Interest or shall make arrangements satisfactory to
the Trustee for such deposit prior to the date of the proposed payment, such
money when deposited to be held in trust for the benefit of the Person entitled
to such Defaulted Interest as in this clause provided. Thereupon the Trustee
shall fix a special record date for the payment of such Defaulted Interest which
shall be not more than fifteen (15) days and not less than ten (10) days prior
to the date of the proposed payment, and not less than ten (10) days after the
receipt by the Trustee of the notice of the proposed payment, the Trustee shall
promptly notify the Company of such special record date and, in the name and at
the expense of the Company, shall cause notice of the proposed payment of such
Defaulted Interest and the special record date therefor to be mailed,
first-class postage prepaid, to each Noteholder at his address as it appears in
the Note register, not less than ten (10) days prior to such special record
date. Notice of the proposed payment of such Defaulted Interest and the special
record date therefor having been so mailed, such Defaulted Interest shall be
paid to the Persons in whose names the Notes (or their respective Predecessor
Notes) were registered at the close of business on such special record date and
shall no longer be payable pursuant to the following clause (2) of this Section
2.3.

                           (2) The Company may make payment of any Defaulted
Interest in any other lawful manner not inconsistent with the requirements of
any securities exchange or automated quotation system on which the Notes may be
listed or designated for issuance, and upon such notice as may be required by
such exchange or automated quotation system, if, after notice given by the
Company to the Trustee of the proposed payment pursuant to this clause, such
manner of payment shall be deemed practicable by the Trustee.

                  Section 2.4. Execution Of Notes. The Notes shall be signed in
the name and on behalf of the Company by the manual or facsimile signature of
its Chairman of the Board, Chief Executive Officer, President or any Vice
President (whether or not designated by a number or numbers or word or words
added before or after the title "Vice President") and attested by the manual or
facsimile signature of its Secretary or any of its Assistant Secretaries or its
Treasurer or any of its Assistant Treasurers (which may be printed, engraved or
otherwise reproduced thereon, by facsimile or otherwise). Only such Notes as
shall bear thereon a certificate of authentication substantially in the form set
forth on the form of Note attached as Exhibit A hereto, manually executed by the
Trustee (or an authenticating agent appointed by the Trustee as provided by
Section 16.11), shall be entitled to the benefits of this Indenture or be valid
or obligatory for any purpose. Such certificate by the Trustee (or such an
authenticating agent) upon any Note executed by the Company shall be conclusive
evidence that the Note so authenticated has been duly authenticated and
delivered hereunder and that the holder is entitled to the benefits of this
Indenture.

                  In case any officer of the Company who shall have signed any
of the Notes shall cease to be such officer before the Notes so signed shall
have been authenticated and delivered by the Trustee, or disposed of by the
Company, such Notes nevertheless may be authenticated and delivered or disposed
of as though the person who signed such Notes had not ceased to be


                                       10
<PAGE>   18
such officer of the Company, and any Note may be signed on behalf of the Company
by such persons as, at the actual date of the execution of such Note, shall be
the proper officers of the Company, although at the date of the execution of
this Indenture any such person was not such an officer.

                  Section 2.5. Exchange And Registration Of Transfer Of Notes;
Restrictions On Transfer; Depositary.

                  (a) The Company shall cause to be kept at the Corporate Trust
         Office a register (the register maintained in such office and in any
         other office or agency of the Company designated pursuant to Section
         5.2 being herein sometimes collectively referred to as the "Note
         register") in which, subject to such reasonable regulations as it may
         prescribe, the Company shall provide for the registration of Notes and
         of transfers of Notes. The Note register shall be in written form or in
         any form capable of being converted into written form within a
         reasonably prompt period of time. The Trustee is hereby appointed "Note
         registrar" for the purpose of registering Notes and transfers of Notes
         as herein provided. The Company may appoint one or more co-registrars
         in accordance with Section 5.2.

                  Upon surrender for registration of transfer of any Note to the
Note registrar or any co-registrar, and satisfaction of the requirements for
such transfer set forth in this Section 2.5, the Company shall execute, and the
Trustee shall authenticate and deliver, in the name of the designated transferee
or transferees, one or more new Notes of any authorized denominations and of a
like aggregate principal amount and bearing such restrictive legends as may be
required by this Indenture.

                  Notes may be exchanged for other Notes of any authorized
denominations and of a like aggregate principal amount, upon surrender of the
Notes to be exchanged at any such office or agency maintained by the Company
pursuant to Section 5.2. Whenever any Notes are so surrendered for exchange, the
Company shall execute, and the Trustee shall authenticate and deliver, the Notes
which the Noteholder making the exchange is entitled to receive bearing
registration numbers not contemporaneously outstanding.

                  All Notes issued upon any registration of transfer or exchange
of Notes shall be the valid obligations of the Company, evidencing the same
debt, and entitled to the same benefits under this Indenture, as the Notes
surrendered upon such registration of transfer or exchange.

                  All Notes presented or surrendered for registration of
transfer or for exchange, redemption or conversion shall (if so required by the
Company or the Note registrar) be duly endorsed, or be accompanied by a written
instrument or instruments of transfer in form satisfactory to the Company, and
the Notes shall be duly executed by the Noteholder thereof or his attorney duly
authorized in writing.

                  No service charge shall be made to any holder for any
registration of transfer or exchange of Notes, but the Company may require
payment by the holder of a sum sufficient to cover any tax, assessment or other
governmental charge that may be imposed in connection with any registration of
transfer or exchange of Notes.



                                       11
<PAGE>   19
                  Neither the Company nor the Trustee nor any Note registrar
shall be required to exchange or register a transfer of (a) any Notes for a
period of fifteen (15) days next preceding any selection of Notes to be
redeemed, (b) any Notes or portions thereof called for redemption pursuant to
Section 3.2, (c) any Notes or portions thereof surrendered for conversion
pursuant to Article Fifteen or (d) any Notes or portions thereof tendered for
redemption (and not withdrawn) pursuant to Section 3.5.

                  (b) So long as the Notes are eligible for book-entry
         settlement with the Depositary, or unless otherwise required by law,
         all Notes that, upon initial issuance are beneficially owned by QIBs or
         as a result of a sale or transfer after initial issuance are
         beneficially owned by QIBs, will be represented by one or more Notes in
         global form registered in the name of the Depositary or the nominee of
         the Depositary (the "Global Note"), except as otherwise specified
         below. The transfer and exchange of beneficial interests in any such
         Global Note shall be effected through the Depositary in accordance with
         this Indenture and the procedures of the Depositary therefor. The
         Trustee shall make appropriate endorsements to reflect increases or
         decreases in the principal amounts of any such Global Note as set forth
         on the face of the Note ("Principal Amount") to reflect any such
         transfers. Except as provided below, beneficial owners of a Global Note
         shall not be entitled to have certificates registered in their names,
         will not receive or be entitled to receive physical delivery of
         certificates in definitive form and will not be considered holders of
         such Global Note.

                  (c) So long as the Notes are eligible for book-entry
         settlement with the Depositary, or unless otherwise required by law,
         upon any transfer of a definitive Note to a QIB in accordance with Rule
         144A, and upon receipt of the definitive Note or Notes being so
         transferred, together with a certification, substantially in the form
         on the reverse of the Note, from the transferor that the transfer is
         being made in compliance with Rule 144A (or other evidence satisfactory
         to the Trustee), the Trustee shall make an endorsement on the Global
         Note to reflect an increase in the aggregate Principal Amount of the
         Notes represented by such Global Note, and the Trustee shall cancel
         such definitive Note or Notes in accordance with the standing
         instructions and procedures of the Depositary, the aggregate Principal
         Amount of the Notes represented by such Global Note to be increased
         accordingly; provided, however, that no definitive Note, or portion
         thereof, in respect of which the Company or an Affiliate of the Company
         held any beneficial interest shall be included in such Global Note
         until such definitive Note is freely tradable in accordance with Rule
         144(k) under the Securities Act, provided further that the Trustee
         shall issue Notes in definitive form upon any transfer of a beneficial
         interest in the Global Note to the Company or any Affiliate of the
         Company.

                  Upon any sale or transfer of a Note to an Institutional
Accredited Investor (other than pursuant to a registration statement that has
been declared effective under the Securities Act), such Institutional Accredited
Investor shall, prior to such sale or transfer, furnish to the Company and/or
the Trustee a signed letter containing representations and agreements relating
to restrictions on transfer substantially in the form set forth in Exhibit B to
this Indenture. Upon any transfer of a beneficial interest in the Global Note to
an Institutional Accredited Investor, the Trustee shall make an endorsement on
the Global Note to reflect a decrease in the aggregate Principal Amount of the
Notes represented by such Global Note, and the Company shall execute


                                       12
<PAGE>   20
a definitive Note or Notes in exchange therefor, and the Trustee, upon receipt
of such definitive Note or Notes and the written order of the Company, shall
authenticate and deliver such, definitive Note or Notes.

                  Any Global Note may be endorsed with or have incorporated in
the text thereof such legends or recitals or changes not inconsistent with the
provisions of this Indenture as may be required by the Custodian, the Depositary
or by the National Association of Securities Dealers, Inc. in order for the
Notes to be tradable on The Portal Market or as may be required for the Notes to
be tradeable on any other market developed for trading of securities pursuant to
Rule 144A or required to comply with any applicable law or any regulation
thereunder or with the rules and regulations of any securities exchange or
automated quotation system upon which the Notes may be listed or traded or to
conform with any usage with respect thereto, or to indicate any special
limitations or restrictions to which any particular Notes are subject.

                  (d) Every Note that bears or is required under this Section
         2.5(d) to bear the legend set forth in this Section 2.5(d) (together
         with any Common Stock issued upon conversion of the Notes and required
         to bear the legend set forth in Section 2.5(e), collectively, the
         "Restricted Securities") shall be subject to the restrictions on
         transfer set forth in this Section 2.5(d) (including those set forth in
         the legend set forth below) unless such restrictions on transfer shall
         be waived by written consent of the Company, and the holder of each
         such Restricted Security, by such Noteholder's acceptance thereof,
         agrees to be bound by all such restrictions on transfer. As used in
         Sections 2.5(d) and 2.5(e), the term "transfer" encompasses any sale,
         pledge, loan, transfer or other disposition whatsoever of any
         Restricted Security.

                  Until the expiration of the holding period applicable to sales
thereof under Rule 144(k) under the Securities Act (or any successor provision),
any certificate evidencing such Note (and all securities issued in exchange
therefor or substitution thereof, other than Common Stock, if any, issued upon
conversion thereof, which shall bear the legend set forth in Section 2.5(e), if
applicable) shall bear a legend in substantially the following form, unless such
Note has been sold pursuant to a registration statement that has been declared
effective under the Securities Act (and which continues to be effective at the
time of such transfer), or unless otherwise agreed by the Company in writing,
with written notice thereof to the Trustee:

         THE NOTE EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE UNITED
         STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR
         ANY STATE SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD
         WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, U.S.
         PERSONS EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE. BY ITS
         ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS THAT (A) IT IS A
         "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER THE
         SECURITIES ACT) OR (B) IT IS AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS
         DEFINED IN RULE 501(A)(1), (2), (3) OR (7) UNDER THE SECURITIES ACT)
         ("INSTITUTIONAL ACCREDITED INVESTOR"); (2) AGREES THAT IT WILL NOT,
         PRIOR TO EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES OF THE
         NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE SECURITIES ACT (OR
         ANY


                                       13
<PAGE>   21
         SUCCESSOR PROVISION), RESELL OR OTHERWISE TRANSFER THE NOTE EVIDENCED
         HEREBY OR THE COMMON STOCK ISSUABLE UPON CONVERSION OF SUCH NOTE EXCEPT
         (A) TO BURR-BROWN CORPORATION OR ANY SUBSIDIARY THEREOF, (B) INSIDE THE
         UNITED STATES TO A QUALIFIED INSTITUTIONAL BUYER IN COMPLIANCE WITH
         RULE 144A UNDER THE SECURITIES ACT, (C) INSIDE THE UNITED STATES TO AN
         INSTITUTIONAL ACCREDITED INVESTOR THAT, PRIOR TO SUCH TRANSFER,
         FURNISHES TO UNITED STATES TRUST COMPANY OF NEW YORK, AS TRUSTEE (OR A
         SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER CONTAINING CERTAIN
         REPRESENTATIONS AND AGREEMENTS RELATING TO THE RESTRICTIONS ON TRANSFER
         OF THE NOTE EVIDENCED HEREBY (THE FORM OF WHICH LETTER CAN BE OBTAINED
         FROM SUCH TRUSTEE OR A SUCCESSOR TRUSTEE, AS APPLICABLE), (D) OUTSIDE
         THE UNITED STATES IN COMPLIANCE WITH RULE 904 UNDER THE SECURITIES ACT,
         (E) PURSUANT TO THE EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144
         UNDER THE SECURITIES ACT (IF AVAILABLE) OR (F) PURSUANT TO A
         REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE UNDER THE
         SECURITIES ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF SUCH
         TRANSFER); (3) PRIOR TO SUCH TRANSFER (OTHER THAN A TRANSFER PURSUANT
         TO CLAUSE (2)(F) ABOVE), IT WILL FURNISH TO UNITED STATES TRUST COMPANY
         OF NEW YORK, AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH
         CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS THE TRUSTEE MAY
         REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT
         TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
         REGISTRATION REQUIREMENTS OF THE SECURITIES ACT; AND (4) AGREES THAT IT
         WILL DELIVER TO EACH PERSON TO WHOM THE NOTE EVIDENCED HEREBY IS
         TRANSFERRED (EXCEPT TRANSFERS PURSUANT TO CLAUSES 2(E) OR 2(F) ABOVE,
         OR PURSUANT TO RULE 144(K)) A NOTICE SUBSTANTIALLY TO THE EFFECT OF
         THIS LEGEND. IN CONNECTION WITH ANY TRANSFER OF THE NOTE EVIDENCED
         HEREBY PRIOR TO THE EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO
         SALES OF THE NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE
         SECURITIES ACT (OR ANY SUCCESSOR PROVISION), THE HOLDER MUST CHECK THE
         APPROPRIATE BOX SET FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER
         OF SUCH TRANSFER AND SUBMIT THIS CERTIFICATE TO UNITED STATES TRUST
         COMPANY OF NEW YORK, AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS
         APPLICABLE). IF THE PROPOSED TRANSFEREE IS AN INSTITUTIONAL ACCREDITED
         INVESTOR OR IS A PURCHASER WHO IS NOT A U.S. PERSON, THE HOLDER MUST,
         PRIOR TO SUCH TRANSFER, FURNISH TO UNITED STATES TRUST COMPANY OF NEW
         YORK, AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH
         CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS SUCH TRUSTEE MAY
         REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT
         TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
         REGISTRATION REQUIREMENTS OF THE SECURITIES ACT.


                                       14
<PAGE>   22
         THIS LEGEND WILL BE REMOVED UPON THE EARLIER OF THE TRANSFER OF THE
         NOTE EVIDENCED HEREBY PURSUANT TO CLAUSES 2(E) OR (2)(F) ABOVE, OR UPON
         ANY TRANSFER OF THE NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE
         SECURITIES ACT (OR ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS
         "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY
         REGULATION S UNDER THE SECURITIES ACT.

                  Any Note (or security issued in exchange or substitution
therefor) as to which such restrictions on transfer shall have expired in
accordance with their terms or as to conditions for removal of the foregoing
legend set forth therein have been satisfied may, upon surrender of such Note
for exchange to the Note registrar in accordance with the provisions of this
Section 2.5, be exchanged for a new Note or Notes, of like tenor and aggregate
principal amount, which shall not bear the restrictive legend required by this
Section 2.5(d).

                  Notwithstanding any other provisions of this Indenture (other
than the provisions set forth in the second paragraph of Section 2.5(c) and in
this Section 2.5(d)), a Global Note may not be transferred as a whole or in part
except by the Depositary to a nominee of the Depositary or by a nominee of the
Depositary to the Depositary or another nominee of the Depositary or by the
Depositary or any such nominee to a successor Depositary or a nominee of such
successor Depositary.
                  The Depositary shall be a clearing agency registered under the
Exchange Act. The Company initially appoints The Depository Trust Company to act
as Depositary with respect to the Notes in global form. Initially, the Global
Note shall be issued to the Depositary, registered in the name of Cede & Co., as
the nominee of the Depositary, and deposited with the Custodian for Cede & Co.

                  If at any time the Depositary for a Global Note notifies the
Company that it is unwilling or unable to continue as Depositary for such Note,
the Company may appoint a successor Depositary with respect to such Note. If a
successor Depositary is not appointed by the Company within ninety (90) days
after the Company receives such notice, the Company will execute, and the
Trustee, upon receipt of an Officers' Certificate for the authentication and
delivery of Notes, will authenticate and deliver, Notes in certificated form, in
aggregate principal amount equal to the principal amount of such Global Note, in
exchange for such Global Note.

                  If a Note in certificated form is issued in exchange for any
portion of a Global Note after the close of business at the office or agency
where such exchange occurs on any record date and before the opening of business
at such office or agency on the next succeeding interest payment date, interest
will not be payable on such interest payment date in respect of such
certificated Note, but will be payable on such interest payment date, subject to
the provisions of Section 2.3, only to the Person to whom interest in respect of
such portion of such Global Note is payable in accordance with the provisions of
this Indenture.

                  Notes in certificated form issued in exchange for all or a
part of a Global Note pursuant to this Section 2.5 shall be registered in such
names and in such authorized denominations as the Depositary, pursuant to
instructions from its direct or indirect participants


                                       15
<PAGE>   23
or otherwise, shall instruct the Trustee. Upon execution and authentication, the
Trustee shall deliver such Notes in certificated form to the Persons in whose
names such Notes in certificated form are so registered.

                  At such time as all interests in a Global Note have been
redeemed, converted, canceled, exchanged for Notes in certificated form, or
transferred to a transferee who receives Notes in certificated form therefor,
such Global Note shall, upon receipt thereof, be canceled by the Trustee in
accordance with standing procedures and instructions existing between the
Depositary and the Custodian. At any time prior to such cancellation, if any
interest in a Global Note is exchanged for Notes in certificated form, redeemed,
converted, repurchased or canceled, or transferred to a transferee who receives
Notes in certificated form therefor or any Note in certificated form is
exchanged or transferred for part of a Global Note, the principal amount of such
Global Note shall, in accordance with the standing procedures and instructions
existing between the Depositary and the Custodian, be appropriately reduced or
increased, as the case may be, and an endorsement shall be made on such Global
Note, by the Trustee or the Custodian, at the direction of the Trustee, to
reflect such reduction or increase.

                  (e) Until the expiration of the holding period applicable to
         sales thereof under Rule 144(k) under the Securities Act (or any
         successor provision), any stock certificate representing Common Stock
         issued upon conversion of any Note shall bear a legend in substantially
         the following form, unless such Common Stock has been sold pursuant to
         a registration statement that has been declared effective under the
         Securities Act (and which continues to be effective at the time of such
         transfer) or such Common Stock has been issued upon conversion of Notes
         that have been transferred pursuant to a registration statement that
         has been declared effective under the Securities Act, or unless
         otherwise agreed by the Company in writing with written notice thereof
         to the transfer agent:

         THE COMMON STOCK EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE
         UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
         ACT"), OR ANY STATE SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE
         OFFERED OR SOLD WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
         BENEFIT OF, U.S. PERSONS EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE.
         THE HOLDER HEREOF AGREES THAT, UNTIL THE EXPIRATION OF THE HOLDING
         PERIOD APPLICABLE TO SALES OF THE COMMON STOCK EVIDENCED HEREBY UNDER
         RULE 144(K) UNDER THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION), (1)
         IT WILL NOT RESELL OR OTHERWISE TRANSFER THE COMMON STOCK EVIDENCED
         HEREBY EXCEPT (A) TO BURR-BROWN CORPORATION OR ANY SUBSIDIARY THEREOF,
         (B) INSIDE THE UNITED STATES TO A "QUALIFIED INSTITUTIONAL BUYER" (AS
         DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN COMPLIANCE WITH RULE
         144A, (C) INSIDE THE UNITED STATES TO AN INSTITUTIONAL "ACCREDITED
         INVESTOR" (AS DEFINED IN RULE 501(A)(1), (2), (3) OR (7) UNDER THE
         SECURITIES ACT) THAT PRIOR TO SUCH TRANSFER, FURNISHES TO HARRIS TRUST
         & SAVINGS BANK, AS TRANSFER AGENT (OR A SUCCESSOR TRANSFER AGENT, AS
         APPLICABLE), A SIGNED LETTER CONTAINING


                                       16
<PAGE>   24
         CERTAIN REPRESENTATIONS AND AGREEMENTS RELATING TO THE RESTRICTIONS ON
         TRANSFER OF THE COMMON STOCK EVIDENCED HEREBY (THE FORM OF WHICH LETTER
         CAN BE OBTAINED FROM SUCH TRANSFER AGENT OR A SUCCESSOR TRANSFER AGENT,
         AS APPLICABLE), (D) OUTSIDE THE UNITED STATES IN COMPLIANCE WITH RULE
         904 UNDER THE SECURITIES LAWS (E) PURSUANT TO THE EXEMPTION FROM
         REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF
         AVAILABLE), OR (F) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN
         DECLARED EFFECTIVE UNDER THE SECURITIES ACT (AND WHICH CONTINUES TO BE
         EFFECTIVE AT THE TIME OF SUCH TRANSFER); (2) PRIOR TO SUCH TRANSFER
         (OTHER THAN A TRANSFER PURSUANT TO CLAUSE (1)(F) ABOVE), IT WILL
         FURNISH TO HARRIS TRUST & SAVINGS BANK, AS TRANSFER AGENT (OR A
         SUCCESSOR TRANSFER AGENT, AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL
         OPINIONS OR OTHER INFORMATION AS SUCH TRANSFER AGENT MAY REASONABLY
         REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN
         EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
         REQUIREMENTS OF THE SECURITIES ACT; AND (3) IT WILL DELIVER TO EACH
         PERSON TO WHOM THE COMMON STOCK EVIDENCED HEREBY IS TRANSFERRED (OTHER
         THAN A TRANSFER PURSUANT TO CLAUSES 1(E) OR 1(F) ABOVE, OR PURSUANT TO
         RULE 144(K)) A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IF
         THE PROPOSED TRANSFEREE IS AN INSTITUTIONAL ACCREDITED INVESTOR OR IS A
         PURCHASER WHO IS NOT A U.S. PERSON, THE HOLDER MUST, PRIOR TO SUCH
         TRANSFER, FURNISH TO HARRIS TRUST & SAVINGS BANK (OR A SUCCESSOR
         TRANSFER AGENT, AS APPLICABLE), SUCH CERTIFICATIONS, LEGAL OPINIONS OR
         OTHER INFORMATION AS IT MAY REASONABLY REQUIRE TO CONFIRM THAT SUCH
         TRANSFER IS BEING MADE PURSUANT TO AN EXEMPTION FROM, OR IN A
         TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE
         SECURITIES ACT. THIS LEGEND WILL BE REMOVED UPON THE EARLIER OF THE
         TRANSFER OF THE COMMON STOCK EVIDENCED HEREBY PURSUANT TO CLAUSES
         (1)(E) OR 1(F) ABOVE, OR UPON ANY TRANSFER OF THE COMMON STOCK
         EVIDENCED HEREBY AFTER THE EXPIRATION OF THE HOLDING PERIOD APPLICABLE
         TO SALES OF THE SECURITY EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE
         SECURITIES ACT (OR ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS
         "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY
         REGULATION S UNDER THE SECURITIES ACT.

                  Any such Common Stock as to which such restrictions on
transfer shall have expired in accordance with their terms or as to which the
conditions for removal of the foregoing legend set forth therein have been
satisfied may, upon surrender of the certificates representing such shares of
Common Stock for exchange in accordance with the procedures of the transfer
agent for the Common Stock, be exchanged for a new certificate or certificates
for a like number of shares of Common Stock, which shall not bear the
restrictive legend required by this Section 2.5(e).



                                       17
<PAGE>   25
                  (f) Any Note or Common Stock issued upon the conversion or
         exchange of a Note that, prior to the expiration of the holding period
         applicable to sales thereof under Rule 144(k) under the Securities Act
         (or any successor provision), is purchased or owned by the Company or
         any Affiliate thereof may not be resold by the Company or such
         Affiliate unless registered under the Securities Act or resold pursuant
         to an exemption from the registration requirements of the Securities
         Act in a transaction which results in such Notes or Common Stock, as
         the case may be, no longer being "restricted securities" (as defined
         under Rule 144).

                  Section 2.6. Mutilated, Destroyed, Lost Or Stolen Notes. In
case any Note shall become mutilated or be destroyed, lost or stolen, the
Company in its discretion may execute, and upon its written request the Trustee
or an authenticating agent appointed by the Trustee shall authenticate and make
available for delivery, a new Note, bearing a number not contemporaneously
outstanding, in exchange and substitution for the mutilated Note, or in lieu of
and in substitution for the Note so destroyed, lost or stolen. In every case the
applicant for a substituted Note shall furnish to the Company, to the Trustee
and, if applicable, to such authenticating agent such security or indemnity as
may be required by them to save each of them harmless for any loss, liability,
cost or expense caused by or connected with such substitution, and, in every
case of destruction, loss or theft, the applicant shall also furnish to the
Company, to the Trustee and, if applicable, to such authenticating agent
evidence to their satisfaction of the destruction, loss or theft of such Note
and of the ownership thereof.

                  Following receipt by the Trustee or such authenticating agent,
as the case may be, of satisfactory security or indemnity and evidence, as
described in the preceding paragraph, the Trustee or such authenticating agent
may authenticate any such substituted Note and make available for delivery such
Note. Upon the issuance of any substituted Note, the Company may require the
payment by the holder of a sum sufficient to cover any tax, assessment or other
governmental charge that may be imposed in relation thereto and any other
expenses connected therewith. In case any Note which has matured or is about to
mature or has been called for redemption or has been tendered for redemption
(and not withdrawn) or is to be converted into Common Stock shall become
mutilated or be destroyed, lost or stolen, the Company may, instead of issuing a
substitute Note, pay or authorize the payment of or convert or authorize the
conversion of the same (without surrender thereof except in the case of a
mutilated Note), as the case may be, if the applicant for such payment or
conversion shall furnish to the Company, to the Trustee and, if applicable, to
such authenticating agent such security or indemnity as may be required by them
to save each of them harmless for any loss, liability, cost or expense caused by
or connected with such substitution, and, in every case of destruction, loss or
theft, the applicant shall also furnish to the Company, the Trustee and, if
applicable, any paying agent or conversion agent evidence to their satisfaction
of the destruction, loss or theft of such Note and of the ownership thereof.

                  Every substitute Note issued pursuant to the provisions of
this Section 2.6 by virtue of the fact that any Note is destroyed, lost or
stolen shall constitute an additional contractual obligation of the Company,
whether or not the destroyed, lost or stolen Note shall be found at any time,
and shall be entitled to all the benefits of (but shall be subject to all the
limitations set forth in) this Indenture equally and proportionately with any
and all other Notes duly issued hereunder. To the extent permitted by law, all
Notes shall be held and owned upon


                                       18
<PAGE>   26
the express condition that the foregoing provisions are exclusive with respect
to the replacement or payment or conversion of mutilated, destroyed, lost or
stolen Notes and shall preclude any and all other rights or remedies
notwithstanding any law or statute existing or hereafter enacted to the contrary
with respect to the replacement or payment or conversion of negotiable
instruments or other securities without their surrender.

                  Section 2.7. Temporary Notes. Pending the preparation of Notes
in certificated form, the Company may execute and the Trustee or an
authenticating agent appointed by the Trustee shall, upon the written request of
the Company, authenticate and deliver temporary Notes (printed or lithographed).
Temporary Notes shall be issuable in any authorized denomination, and
substantially in the form of the Notes in certificated form, but with such
omissions, insertions and variations as may be appropriate for temporary Notes,
all as may be determined by the Company. Every such temporary Note shall be
executed by the Company and authenticated by the Trustee or such authenticating
agent upon the same conditions and in substantially the same manner, and with
the same effect, as the Notes in certificated form. Without unreasonable delay
the Company will execute and deliver to the Trustee or such authenticating agent
Notes in certificated form (other than in the case of Notes in global form) and
thereupon any or all temporary Notes (other than any such Global Note) may be
surrendered in exchange therefor, at each office or agency maintained by the
Company pursuant to Section 5.2 and the Trustee or such authenticating agent
shall authenticate and make available for delivery in exchange for such
temporary Notes an equal aggregate principal amount of Notes in certificated
form. Such exchange shall be made by the Company at its own expense and without
any charge therefor. Until so exchanged, the temporary Notes shall in all
respects be entitled to the same benefits and subject to the same limitations
under this Indenture as Notes in certificated form authenticated and delivered
hereunder.

                  Section 2.8. Cancellation Of Notes Paid, Etc. All Notes
surrendered for the purpose of payment, redemption, conversion, exchange or
registration of transfer shall, if surrendered to the Company or any paying
agent or any Note registrar or any conversion agent, be surrendered to the
Trustee and promptly canceled by it, or, if surrendered to the Trustee, shall be
promptly canceled by it, and no Notes shall be issued in lieu thereof except as
expressly permitted by any of the provisions of this Indenture. The Trustee
shall dispose of such canceled Notes in accordance with its customary
procedures. If the Company shall acquire any of the Notes, such acquisition
shall not operate as a redemption or satisfaction of the indebtedness
represented by such Notes unless and until the same are delivered to the Trustee
for cancellation.

                  Section 2.9. CUSIP Numbers. The Company in issuing the Notes
may use "CUSIP" numbers (if then generally in use), and, if so, the Trustee
shall use "CUSIP" numbers in notices of redemption as a convenience to
Noteholders; provided, however, that any such notice may state that no
representation is made as to the correctness of such numbers either as printed
on the Notes or as contained in any notice of a redemption and that reliance may
be placed only on the other identification numbers printed on the Notes, and any
such redemption shall not be affected by any defect in or omission of such
numbers. The Company will promptly notify the Trustee of any change in the
"CUSIP" numbers.



                                       19
<PAGE>   27
                                   ARTICLE 3.

                               REDEMPTION OF NOTES

                  Section 3.1. (a) Initial Prohibition On Redemption. Except as
otherwise provided in Section 3.5, the Notes may not be redeemed by the Company,
in whole or in part, at any time prior to February 20, 2003.

                  (b) Optional Redemption By The Company. At any time on or
after February 20, 2003, and prior to maturity, the Notes may be redeemed at the
option of the Company, in whole or in part, upon notice as set forth in Section
3.2, at the following redemption prices (expressed as percentages of the
principal amount), together in each case with accrued and unpaid interest, if
any (including Liquidated Damages, if any) to, but excluding, the date fixed for
redemption:

<TABLE>
<CAPTION>
         Period                                                                    Redemption Price
         ------                                                                    ----------------

<S>                                                                                <C>
         Beginning on February 20, 2003 and ending on February 14, 2004...........     102.429%
         Beginning on February 15, 2004 and ending on February 14, 2005...........     101.821
         Beginning on February 15, 2005 and ending on February 14, 2006...........     101.214
         Beginning on February 15, 2006 and ending on February 14, 2007...........     100.607
</TABLE>

and 100% on February 15, 2007; provided, however, that if the date fixed for
redemption is on a February 15 or August 15, then the interest payable on such
date shall be paid to the holder of record on the preceding February 1 or August
1, respectively.

                  Section 3.2. Notice Of Redemptions; Selection Of Notes. In
case the Company shall desire to exercise the right to redeem all or, as the
case may be, any part of the Notes pursuant to Section 3.1, it shall fix a date
for redemption and it or, at its written request received by the Trustee not
fewer than forty-five (45) days prior (or such shorter period of time as may be
acceptable to the Trustee) to the date fixed for redemption, the Trustee in the
name of and at the expense of the Company, shall mail or cause to be mailed in
the manner as hereinafter provided a notice of such redemption not fewer than
thirty (30) nor more than sixty (60) days prior to the date fixed for redemption
to the holders of Notes so to be redeemed as a whole or in part at their last
addresses as the same appear on the Note register; provided, however, that if
the Company shall give such notice, it shall also give written notice, and
written notice of the Notes to be redeemed, to the Trustee. Such mailing shall
be by first class mail. The notice if mailed in the manner herein provided shall
be conclusively presumed to have been duly given, whether or not the holder
receives such notice. In any case, failure to give such notice by mail or any
defect in the notice to the holder of any Note designated for redemption as a
whole or in part shall not affect the validity of the proceedings for the
redemption of any other Note. Concurrently with the mailing of any such notice
of redemption, the Company shall issue a press release announcing such
redemption, the form and content of which press release shall be determined by
the Company in its sole discretion. The failure to issue any such press release
or any defect therein shall not affect the validity of the redemption notice or
any of the proceedings for the redemption of any Note called for redemption.



                                       20
<PAGE>   28
                  Each such notice of redemption shall specify the aggregate
principal amount of Notes to be redeemed, the CUSIP number or numbers of the
Notes being redeemed, the date fixed for redemption (which shall be a Business
Day), the redemption price at which Notes are to be redeemed, the place or
places of payment, that payment will be made upon presentation and surrender of
such Notes, that interest accrued to the date fixed for redemption will be paid
as specified in said notice, and that on and after said date interest thereon or
on the portion thereof to be redeemed will cease to accrue. Such notice shall
also state the current Conversion Price and the date on which the right to
convert such Notes or portions thereof into Common Stock will expire. If fewer
than all the Notes are to be redeemed, the notice of redemption shall identify
the Notes to be redeemed (including CUSIP numbers, if any). In case any Note is
to be redeemed in part only, the notice of redemption shall state the portion of
the principal amount thereof to be redeemed and shall state that, on and after
the date fixed for redemption, upon surrender of such Note, a new Note or Notes
in principal amount equal to the unredeemed portion thereof will be issued.

                  On or prior to the redemption date specified in the notice of
redemption given as provided in this Section 3.2, the Company will deposit with
the Trustee or with one or more paying agents (or, if the Company is acting as
its own paying agent, set aside, segregate and hold in trust as provided in
Section 5.4) an amount of money in immediately available funds sufficient to
redeem on the redemption date all the Notes (or portions thereof) so called for
redemption (other than those theretofore surrendered for conversion into Common
Stock) at the appropriate redemption price, together with accrued interest to,
but excluding, the date fixed for redemption; provided, however, that if such
payment is made on the redemption date it must be received by the Trustee or
paying agent, as the case may be, by 10:00 a.m. New York City time on such date.
The Company shall be entitled to retain any interest, yield or gain on amounts
deposited with the Trustee or any paying agent pursuant to this Section 3.2 in
excess of amounts required hereunder to pay the redemption price together with
accrued interest to, but excluding, the date fixed for redemption. If any Note
called for redemption is converted pursuant hereto prior to such redemption, any
money deposited with the Trustee or any paying agent or so segregated and held
in trust for the redemption of such Note shall be paid to the Company upon its
written request, or, if then held by the Company, shall be discharged from such
trust. Whenever any Notes are to be redeemed, the Company will give the Trustee
written notice in the form of an Officers' Certificate not fewer than forty-five
(45) days (or such shorter period of time as may be acceptable to the Trustee)
prior to the redemption date as to the aggregate principal amount of Notes to be
redeemed.

                  If less than all of the outstanding Notes are to be redeemed,
the Trustee shall select the Notes or portions thereof of the Global Note or the
Notes in certificated form to be redeemed (in principal amounts of $1,000 or
integral multiples thereof) by lot, on a pro rata basis or by another method the
Trustee deems fair and appropriate. If any Note selected for partial redemption
is submitted for conversion in part after such selection, the portion of such
Note submitted for conversion shall be deemed (so far as may be) to be the
portion to be selected for redemption. The Notes (or portions thereof) so
selected shall be deemed duly selected for redemption for all purposes hereof,
notwithstanding that any such Note is submitted for conversion in part before
the mailing of the notice of redemption.



                                       21
<PAGE>   29
         Upon any redemption of less than all of the outstanding Notes, the
Company and the Trustee may (but need not), solely for purposes of determining
the pro rata allocation among such Notes as are unconverted and outstanding at
the time of redemption, treat as outstanding any Notes surrendered for
conversion during the period of fifteen (15) days next preceding the mailing of
a notice of redemption and may (but need not) treat as outstanding any Note
authenticated and delivered during such period in exchange for the unconverted
portion of any Note converted in part during such period.

         Section 3.3. Payment Of Notes Called For Redemption. If notice of
redemption has been given as above provided, the Notes or portion of Notes with
respect to which such notice has been given shall, unless converted into Common
Stock pursuant to the terms hereof, become due and payable on the date fixed for
redemption and at the place or places stated in such notice at the applicable
redemption price, together with interest accrued to (but excluding) the date
fixed for redemption, and on and after said date (unless the Company shall
default in the payment of such Notes at the redemption price, together with
interest accrued to said date) interest on the Notes or portion of Notes so
called for redemption shall cease to accrue and, after the close of business on
the Business Day next preceding the date fixed for redemption, such Notes shall
cease to be convertible into Common Stock and, except as provided in Sections
8.5 and 13.4, to be entitled to any benefit or security under this Indenture,
and the holders thereof shall have no right in respect of such Notes except the
right to receive the redemption price thereof and unpaid interest to (but
excluding) the date fixed for redemption. On presentation and surrender of such
Notes at a place of payment in said notice specified, the said Notes or the
specified portions thereof shall be paid and redeemed by the Company at the
applicable redemption price, together with interest accrued thereon to (but
excluding) the date fixed for redemption; provided, however, that if the
applicable redemption date is an interest payment date, the semi-annual payment
of interest becoming due on such date shall be payable to the holders of such
Notes registered as such on the relevant record date instead of the holders
surrendering such Notes for redemption on such date.

         Upon presentation of any Note redeemed in part only, the Company shall
execute and the Trustee shall authenticate and make available for delivery to
the holder thereof, at the expense of the Company, a new Note or Notes, of
authorized denominations, in principal amount equal to the unredeemed portion of
the Notes so presented.

         Notwithstanding the foregoing, the Trustee shall not redeem any Notes
or mail any notice of redemption during the continuance of a default in payment
of interest or premium, if any, on the Notes. If any Note called for redemption
shall not be so paid upon surrender thereof for redemption, the principal and
premium, if any, shall, until paid or duly provided for, bear interest from the
date fixed for redemption at the rate borne by the Note and such Note shall
remain convertible into Common Stock until the principal and premium, if any,
and interest shall have been paid or duly provided for.

         Section 3.4. Conversion Arrangement On Call For Redemption. In
connection with any redemption of Notes, the Company may arrange for the
purchase and conversion of any Notes by an agreement with one or more investment
bankers or other purchasers to purchase such Notes by paying to the Trustee in
trust for the Noteholders, on or before the date fixed for redemption, an amount
not less than the applicable redemption price, together with interest

                                       22
<PAGE>   30
accrued to (but excluding) the date fixed for redemption, of such Notes.
Notwithstanding anything to the contrary contained in this Article Three, the
obligation of the Company to pay the redemption price of such Notes, together
with interest accrued to (but excluding) the date fixed for redemption, shall be
deemed to be satisfied and discharged to the extent such amount is so paid by
such purchasers. If such an agreement is entered into, a copy of which will be
filed with the Trustee prior to the date fixed for redemption, any Notes not
duly surrendered for conversion by the holders thereof may, at the option of the
Company, be deemed, to the fullest extent permitted by law, acquired by such
purchasers from such holders and (notwithstanding anything to the contrary
contained in Article Fifteen) surrendered by such purchasers for conversion, all
as of immediately prior to the close of business on the date fixed for
redemption (and the right to convert any such Notes shall be extended through
such time), subject to payment of the above amount as aforesaid. At the
direction of the Company, the Trustee shall hold and dispose of any such amount
paid to it in the same manner as it would monies deposited with it by the
Company for the redemption of Notes. Without the Trustee's prior written
consent, no arrangement between the Company and such purchasers for the purchase
and conversion of any Notes shall increase or otherwise affect any of the
powers, duties, responsibilities or obligations of the Trustee as set forth in
this Indenture.

          Section 3.5. Redemption At Option Of Holders.
                       -------------------------------

          (a)  If there shall occur a Fundamental Change at any time prior to
     maturity of the Notes, then each Noteholder shall have the right, at such
     holder's option, to require the Company to redeem all of such holder's
     Notes, or any portion thereof that is an integral multiple of $1,000
     principal amount, on the date (the "Repurchase Date") that is thirty (30)
     days after the date of the Company Notice (as defined in Section 3.5(b)
     below) of such Fundamental Change (or, if such 30th day is not a Business
     Day, the next succeeding Business Day) at a redemption price equal to 100%
     of the principal amount thereof, together with accrued interest to (but
     excluding) the Repurchase Date; provided, however, that, if such Repurchase
     Date is a February 15 or August 15, then the interest payable on such date
     shall be paid to the holders of record of the Notes on the next preceding
     February 1 or August 1, respectively.

          Upon presentation of any Note redeemed in part only, the Company shall
execute and, upon the Company's written direction to the Trustee, the Trustee
shall authenticate and deliver to the holder thereof, at the expense of the
Company, a new Note or Notes, of authorized denominations, in principal amount
equal to the unredeemed portion of the Notes so presented.

          (b)  On or before the tenth day after the occurrence of a Fundamental
     Change, the Company or at its written request (which must be received by
     the Trustee at least five (5) Business Days prior to the date the Trustee
     is requested to give notice as described below, unless the Trustee shall
     agree in writing to a shorter period), the Trustee, in the name of and at
     the expense of the Company, shall mail or cause to be mailed to all holders
     of record on the date of the Fundamental Change a notice (the "Company
     Notice") of the occurrence of such Fundamental Change and of the redemption
     right at the option of the holders arising as a result thereof. Such notice
     shall be mailed in the manner and with the effect set forth in the first
     paragraph of Section 3.2 (without regard for the time limits set forth
     therein). If the Company shall give such notice, the Company

                                       23
<PAGE>   31
         shall also deliver a copy of the Company Notice to the Trustee at such
         time as it is mailed to Noteholders. Concurrently with the mailing of
         any Company Notice, the Company shall issue a press release announcing
         such Fundamental Change referred to in the Company Notice, the form and
         content of which press release shall be determined by the Company in
         its sole discretion. The failure to issue any such press release or any
         defect therein shall not affect the validity of the Company Notice or
         any proceedings for the redemption of any Note which any Noteholder may
         elect to have the Company redeem as provided in this Section 3.5.

              Each Company Notice shall specify the circumstances constituting
the Fundamental Change, the Repurchase Date, the price at which the Company
shall be obligated to redeem Notes, that the holder must exercise the redemption
right on or prior to the close of business on the Repurchase Date (the
"Fundamental Change Expiration Time"), that the holder shall have the right to
withdraw any Notes surrendered prior to the Fundamental Change Expiration Time,
a description of the procedure which a Noteholder must follow to exercise such
redemption right and to withdraw any surrendered Notes, the place or places
where the holder is to surrender such holder's Notes, the amount of interest
accrued on each Note to the Repurchase Date and the "CUSIP" number or numbers of
the Notes (if then generally in use).

              No failure of the Company to give the foregoing notices and no
defect therein shall limit the Noteholders' redemption rights or affect the
validity of the proceedings for the redemption of the Notes pursuant to this
Section 3.5.

              (c)  For a Note to be so redeemed at the option of the holder, the
         Company must receive at the office or agency of the Company maintained
         for that purpose or, at the option of such holder, the Corporate Trust
         Office, such Note with the form entitled "Option to Elect Repayment
         Upon A Fundamental Change" on the reverse thereof duly completed,
         together with such Notes duly endorsed for transfer, on or before the
         Fundamental Change Expiration Time. All questions as to the validity,
         eligibility (including time of receipt) and acceptance of any Note for
         repayment shall be determined by the Company, whose determination shall
         be final and binding absent manifest error.

              (d)  The Company will deposit with the Trustee or with one or more
         paying agents (or, if the Company is acting as its own paying agent,
         set aside, segregate and hold in trust as provided in Section 5.4) an
         amount of money sufficient to redeem all the Notes to be redeemed at
         the appropriate redemption price, together with accrued interest to
         (but excluding) the Repurchase Date; provided, however, that if such
         payment is made on the Repurchase Date it must be received by the
         Trustee or paying agent, as the case may be, by 10:00 a.m. New York
         City time, on such date. Payment for Notes surrendered for redemption
         (and not withdrawn) prior to the Fundamental Change Expiration Time
         will be made promptly (but in no event more than five (5) Business
         Days) following the Repurchase Date by mailing checks for the amount
         payable to the holders of such Notes entitled thereto as they shall
         appear on the registry books of the Company.

              (e)  In the case of a reclassification, change, consolidation,
         merger, combination, sale or conveyance to which Section 15.6 applies,
         in which the Common Stock of the Company is changed or exchanged as a
         result into the right to receive stock,

                                       24
<PAGE>   32
         securities or other property or assets (including cash), which includes
         shares of Common Stock of the Company or shares of common stock of
         another Person that are, or upon issuance will be, traded on a United
         States national securities exchange or approved for trading on an
         established automated over-the-counter trading market in the United
         States and such shares constitute at the time such change or exchange
         becomes effective in excess of 50% of the aggregate fair market value
         of such stock, securities or other property or assets (including cash)
         (as determined by the Company, which determination shall be conclusive
         and binding), then the Person formed by such consolidation or resulting
         from such merger or which acquires such assets, as the case may be,
         shall execute and deliver to the Trustee a supplemental indenture
         (accompanied by an Opinion of Counsel that such supplemental indenture
         complies with the Trust Indenture Act as in force at the date of
         execution of such supplemental indenture) modifying the provisions of
         this Indenture relating to the right of holders of the Notes to cause
         the Company to repurchase the Notes following a Fundamental Change,
         including without limitation the applicable provisions of this Section
         3.5 and the definitions of Common Stock and Fundamental Change, as
         appropriate, as determined in good faith by the Company (which
         determination shall be conclusive and binding), to make such provisions
         apply to such other Person if different from the Company and the common
         stock issued by such Person (in lieu of the Company and the Common
         Stock of the Company).

              (f)  The Company will comply with the provisions of Rule 13e-4 and
         any other tender offer rules under the Exchange Act to the extent then
         applicable in connection with the redemption rights of the holders of
         Notes in the event of a Fundamental Change.

                                   ARTICLE 4.

                             SUBORDINATION OF NOTES

              Section 4.1. Agreement Of Subordination. The Company covenants and
agrees, and each holder of Notes issued hereunder by its acceptance thereof
likewise covenants and agrees, that all Notes shall be issued subject to the
provisions of this Article Four, and each Person holding any Note, whether upon
original issue or upon registration of transfer, assignment or exchange thereof,
accepts and agrees to be bound by such provisions.

              The payment of the principal of, premium, if any, and interest
(including Liquidated Damages, if any) on all Notes (including, but not limited
to, the redemption price with respect to the Notes called for redemption in
accordance with Section 3.2 or submitted for redemption in accordance with
Section 3.5, as the case may be, as provided in this Indenture) issued hereunder
shall, to the extent and in the manner hereinafter set forth, be subordinated
and subject in right of payment to the prior payment in full of all Senior
Indebtedness, whether outstanding at the date of this Indenture or thereafter
incurred.

              No provision of this Article Four shall prevent the occurrence of
any default or Event of Default hereunder.

                                       25
<PAGE>   33
              Section 4.2. Payments To Noteholders. No payment shall be made
with respect to the principal of, premium, if any, or interest (including
Liquidated Damages, if any) on the Notes (including, but not limited to, the
redemption price with respect to the Notes to be called for redemption in
accordance with Section 3.2 or submitted for redemption in accordance with
Section 3.5, as the case may be, as provided in this Indenture), except payments
and distributions made by the Trustee as permitted by the first or second
paragraph of Section 4.5, if:

              (i)  a default in the payment of principal, premium, if any,
         interest, rent or other obligations in respect of Designated Senior
         Indebtedness occurs and is continuing (or, in the case of Designated
         Senior Indebtedness for which there is a period of grace, in the event
         of such a default that continues beyond the period of grace, if any,
         specified in the instrument or lease evidencing such Designated Senior
         Indebtedness) (a "Payment Default"), unless and until such Payment
         Default shall have been cured or waived or shall have ceased to exist;
         or

              (ii)  a default, other than a Payment Default, on any Designated
         Senior Indebtedness occurs and is continuing that then permits holders
         of such Designated Senior Indebtedness to accelerate its maturity (or
         in the case of any lease, a default occurs and is continuing that
         permits the lessor to either terminate the lease or require the Company
         to make an irrevocable offer to terminate the lease following an event
         of default thereunder) and the Trustee receives a notice of the default
         (a "Payment Blockage Notice") from a holder of Designated Senior
         Indebtedness, a Representative of Designated Senior Indebtedness or the
         Company (a "Non-Payment Default").

              If the Trustee receives any Payment Blockage Notice pursuant to
clause (ii) above, no subsequent Payment Blockage Notice shall be effective for
purposes of this Section 4.2 unless and until at least 365 days shall have
elapsed since the initial effectiveness of the immediately prior Payment
Blockage Notice. No Non-Payment Default that existed or was continuing on the
date of delivery of any Payment Blockage Notice to the Trustee shall be, or be
made, the basis for a subsequent Payment Blockage Notice.

              The Company may and shall resume payments on and distributions in
respect of the Notes upon the earlier of:

                  (1)      the date upon which any such Payment Default is cured
or waived or ceases to exist, or

                  (2)      in the case of a Non-Payment Default, the earlier of
(a) the date upon which such default is cured or waived or ceases to exist or
(b) 179 days after the applicable Payment Blockage Notice is received by the
Trustee if the maturity of such Designated Senior Indebtedness has not been
accelerated (or in the case of any lease, 179 days after notice is received if
the Company has not received notice that the lessor under such lease has
exercised its right to terminate the lease or require the Company to make an
irrevocable offer to terminate the lease following an event of default
thereunder), unless this Article Four otherwise prohibits the payment or
distribution at the time of such payment or distribution.

              Upon any payment by the Company, or distribution of assets of the
Company of any kind or character, whether in cash, property or securities, to
creditors upon any dissolution or

                                       26
<PAGE>   34
winding up or liquidation or reorganization of the Company, whether voluntary or
involuntary or in bankruptcy, insolvency, receivership or other proceedings, all
amounts due or to become due upon all Senior Indebtedness shall first be paid in
full in cash or other payment satisfactory to the holders of such Senior
Indebtedness (and satisfactory to the holders of Designated Senior Indebtedness
in the case such Senior Indebtedness includes Designated Senior Indebtedness),
or payment thereof in accordance with its terms provided for in cash or other
payment satisfactory to the holders of such Senior Indebtedness (and
satisfactory to the holders of Designated Senior Indebtedness in the case such
Senior Indebtedness includes Designated Senior Indebtedness) before any payment
is made on account of the principal of, premium, if any, or interest (including
Liquidated Damages, if any) on the Notes (except payments made pursuant to
Article Thirteen from monies deposited with the Trustee pursuant thereto prior
to commencement of proceedings for such dissolution, winding up, liquidation or
reorganization), and upon any such dissolution or winding up or liquidation or
reorganization of the Company or bankruptcy, insolvency, receivership or other
similar proceeding, any payment by the Company, or distribution of assets of the
Company of any kind or character, whether in cash, property or securities, to
which the holders of the Notes or the Trustee would be entitled, except for the
provisions of this Article Four, shall (except as aforesaid) be paid by the
Company or by any receiver, trustee in bankruptcy, liquidating trustee, agent or
other Person making such payment or distribution, or by the holders of the Notes
or by the Trustee under this Indenture if received by them or it, directly to
the holders of Senior Indebtedness (pro rata to such holders on the basis of the
respective amounts of Senior Indebtedness held by such holders, or as otherwise
required by law or a court order) or their Representative or Representatives, as
their respective interests may appear, to the extent necessary to pay all Senior
Indebtedness in full, in cash or other payment satisfactory to the holders of
such Senior Indebtedness (and satisfactory to the holders of Designated Senior
Indebtedness in the case such Senior Indebtedness includes Designated Senior
Indebtedness), after giving effect to any concurrent payment or distribution to
or for the holders of Senior Indebtedness, before any payment or distribution is
made to the holders of the Notes or to the Trustee.

         For purposes of this Article Four, the words, "cash, property or
securities" shall not be deemed to include shares of stock of the Company as
reorganized or readjusted, or securities of the Company or any other corporation
provided for by a plan of reorganization or readjustment, the payment of which
is subordinated at least to the extent provided in this Article Four with
respect to the Notes to the payment of all Senior Indebtedness which may at the
time be outstanding, provided that (i) the Senior Indebtedness is assumed by the
new corporation, if any, resulting from any reorganization or readjustment, and
(ii) the rights of the holders of Senior Indebtedness (other than leases which
are not assumed by the Company or the new corporation, as the case may be) are
not, without the consent of such holders, altered by such reorganization or
readjustment. The consolidation of the Company with, or the merger of the
Company into, another corporation or the liquidation or dissolution of the
Company following the conveyance or transfer of its property as an entirety, or
substantially as an entirety, to another Person upon the terms and conditions
provided for in Article Twelve shall not be deemed a dissolution, winding-up,
liquidation or reorganization for the purposes of this Section 4.2 if such other
Person shall, as a part of such consolidation, merger, conveyance or transfer,
comply with the conditions stated in Article Twelve.

                                       27
<PAGE>   35
         In the event of the acceleration of the Notes because of an Event of
Default, no payment or distribution shall be made to the Trustee or any holder
of Notes in respect of the principal of, premium, if any, or interest (including
Liquidated Damages, if any) on the Notes (including, but not limited to, the
redemption price with respect to the Notes called for redemption in accordance
with Section 3.2 or submitted for redemption in accordance with Section 3.5, as
the case may be, as provided in this Indenture), except payments and
distributions made by the Trustee as permitted by the first or second paragraph
of Section 4.5, until all Senior Indebtedness has been paid in full in cash or
other payment satisfactory to the holders of Senior Indebtedness (and
satisfactory to the holders of Designated Senior Indebtedness in the case such
Senior Indebtedness includes Designated Senior Indebtedness) or such
acceleration is rescinded in accordance with the terms of this Indenture. If
payment of the Notes is accelerated because of an Event of Default, the Company
or the Trustee shall promptly notify holders of Senior Indebtedness (including
the agent under the Credit Agreement) of the acceleration.

         In the event that, notwithstanding the foregoing provisions, any
payment or distribution of assets of the Company of any kind or character,
whether in cash, property or securities (including, without limitation, by way
of setoff or otherwise), prohibited by the foregoing provisions in this Section
4.2, shall be received by the Trustee or the holders of the Notes before all
Senior Indebtedness is paid in full in cash or other payment satisfactory to the
holders of such Senior Indebtedness (and satisfactory to the holders of
Designated Senior Indebtedness in the case such Senior Indebtedness includes
Designated Senior Indebtedness), or provision is made for such payment thereof
in accordance with its terms in cash or other payment satisfactory to the
holders of such Senior Indebtedness (and satisfactory to the holders of
Designated Senior Indebtedness in the case such Senior Indebtedness includes
Designated Senior Indebtedness), such payment or distribution shall be held in
trust for the benefit of and shall be paid over or delivered to the holders of
Senior Indebtedness or their Representative or Representatives, as their
respective interests may appear, as calculated by the Company, for application
to the payment of any Senior Indebtedness remaining unpaid to the extent
necessary to pay all Senior Indebtedness in full in cash or other payment
satisfactory to the holders of such Senior Indebtedness (and satisfactory to the
holders of Designated Senior Indebtedness in the case such Senior Indebtedness
includes Designated Senior Indebtedness), after giving effect to any concurrent
payment or distribution to or for the holders of such Senior Indebtedness.

         Nothing in this Section 4.2 shall apply to claims of, or payments to,
the Trustee under or pursuant to Section 8.6. This Section 4.2 shall be subject
to the further provisions of Section 4.5.

         Section 4.3. Subrogation Of Notes. Subject to the payment in full of
all Senior Indebtedness, the rights of the holders of the Notes shall be
subrogated to the extent of the payments or distributions made to the holders of
such Senior Indebtedness pursuant to the provisions of this Article Four
(equally and ratably with the holders of all indebtedness of the Company which
by its express terms is subordinated to other indebtedness of the Company to
substantially the same extent as the Notes are subordinated and is entitled to
like rights of subrogation) to the rights of the holders of Senior Indebtedness
to receive payments or distributions of cash, property or securities of the
Company applicable to the Senior Indebtedness until the principal, premium, if
any, and interest (including Liquidated Damages, if any) on the Notes shall be
paid in full, and, for the purposes of such subrogation, no payments or

                                       28
<PAGE>   36
distributions to the holders of the Senior Indebtedness of any cash, property or
securities to which the holders of the Notes or the Trustee would be entitled
except for the provisions of this Article Four, and no payment pursuant to the
provisions of this Article Four, to or for the benefit of the holders of Senior
Indebtedness by holders of the Notes or the Trustee, shall, as among the
Company, its creditors other than holders of Senior Indebtedness, and the
holders of the Notes, be deemed to be a payment by the Company to or on account
of the Senior Indebtedness, and no payments or distributions of cash, property
or securities to or for the benefit of the holders of the Notes pursuant to the
subrogation provisions of this Article Four, which would otherwise have been
paid to the holders of Senior Indebtedness, shall be deemed to be a payment by
the Company to or for the account of the Notes. It is understood that the
provisions of this Article Four are intended solely for the purposes of defining
the relative rights of the holders of the Notes, on the one hand, and the
holders of the Senior Indebtedness, on the other hand.

         Nothing contained in this Article Four or elsewhere in this Indenture
or in the Notes is intended to or shall impair, as among the Company, its
creditors other than the holders of Senior Indebtedness, and the holders of the
Notes, the obligation of the Company, which is absolute and unconditional, to
pay to the holders of the Notes the principal of, premium, if any, and interest
(including Liquidated Damages, if any) on the Notes as and when the same shall
become due and payable in accordance with their terms, or is intended to or
shall affect the relative rights of the holders of the Notes and creditors of
the Company other than the holders of the Senior Indebtedness, nor shall
anything herein or therein prevent the Trustee or the holder of any Note from
exercising all remedies otherwise permitted by applicable law upon default under
this Indenture, subject to the rights, if any, under this Article Four of the
holders of Senior Indebtedness in respect of cash, property or securities of the
Company received upon the exercise of any such remedy.

         Upon any payment or distribution of assets of the Company referred to
in this Article Four, the Trustee, subject to the provisions of Section 8.1, and
the holders of the Notes shall be entitled to rely upon any order or decree made
by any court of competent jurisdiction in which such bankruptcy, dissolution,
winding up, liquidation or reorganization proceedings are pending, or a
certificate of the receiver, trustee in bankruptcy, liquidating trustee, agent
or other Person making such payment or distribution, delivered to the Trustee or
to the holders of the Notes, for the purpose of ascertaining the Persons
entitled to participate in such distribution, the holders of the Senior
Indebtedness and other indebtedness of the Company, the amount thereof or
payable thereon and all other facts pertinent thereto or to this Article Four.

         Section 4.4. Authorization To Effect Subordination. Each holder of a
Note by the holder's acceptance thereof authorizes and directs the Trustee on
the holder's behalf to take such action as may be necessary or appropriate to
effectuate the subordination as provided in this Article Four and appoints the
Trustee to act as the holder's attorney-in-fact for any and all such purposes.
If the Trustee does not file a proper proof of claim or proof of debt in the
form required in any proceeding referred to in the third paragraph of Section
7.2 hereof at least thirty (30) days before the expiration of the time to file
such claim, the holders of any Senior Indebtedness or their Representatives are
hereby authorized to file an appropriate claim for and on behalf of the holders
of the Notes.

                                       29
<PAGE>   37
         Section 4.5. Notice To Trustee. The Company shall give prompt written
notice in the form of an Officers' Certificate to a Responsible Officer of the
Trustee and to any paying agent of any fact known to the Company that would
prohibit the making of any payment of monies to or by the Trustee or any paying
agent in respect of the Notes pursuant to the provisions of this Article Four.
Notwithstanding the provisions of this Article Four or any other provision of
this Indenture, the Trustee shall not be charged with knowledge of the existence
of any facts that would prohibit the making of any payment of monies to or by
the Trustee in respect of the Notes pursuant to the provisions of this Article
Four, unless and until a Responsible Officer of the Trustee shall have received
written notice thereof at the Corporate Trust Office from the Company (in the
form of an Officers' Certificate) or a Representative or a holder or holders of
Senior Indebtedness, and before the receipt of any such written notice, the
Trustee, subject to the provisions of Section 8.1, shall be entitled in all
respects to assume that no such facts exist; provided, however, that if on a
date not less than one Business Day prior to the date upon which by the terms
hereof any such monies may become payable for any purpose (including, without
limitation, the payment of the principal of, or premium, if any, or interest
(including Liquidated Damages, if any) on any Note) the Trustee shall not have
received, with respect to such monies, the notice provided for in this Section
4.5, then, anything herein contained to the contrary notwithstanding, the
Trustee shall have full power and authority to apply monies received to the
purpose for which they were received, and shall not be affected by any notice to
the contrary that may be received by it on or after such prior date.

         Notwithstanding anything in this Article Four to the contrary, nothing
shall prevent any payment by the Trustee to the Noteholders of monies deposited
with it pursuant to Section 13.1, if a Responsible Officer of the Trustee shall
not have received written notice at the Corporate Trust Office on or before one
Business Day prior to the date such payment is due that such deposit was not
permitted under Section 4.1 or 4.2 at the time such deposit was made.

         The Trustee, subject to the provisions of Section 8.1, shall be
entitled to rely on the delivery to it of a written notice by a Representative
or a person representing himself to be a holder of Senior Indebtedness (or a
trustee on behalf of such holder) to establish that such notice has been given
by a Representative or a holder of Senior Indebtedness or a trustee on behalf of
any such holder or holders. The Trustee shall not be required to make any
payment or distribution to or on behalf of a holder of Senior Indebtedness
pursuant to this Article Four unless it has received satisfactory evidence as to
the amount of Senior Indebtedness held by such Person, the extent to which such
Person is entitled to participate in such payment or distribution and any other
facts pertinent to the rights of such Person under this Article Four.

         Section 4.6. Trustee's Relation To Senior Indebtedness. The Trustee, in
its individual capacity, shall be entitled to all the rights set forth in this
Article Four in respect of any Senior Indebtedness at any time held by it, to
the same extent as any other holder of Senior Indebtedness, and nothing in
Section 8.13 or elsewhere in this Indenture shall deprive the Trustee of any of
its rights as such holder.

         With respect to the holders of Senior Indebtedness, the Trustee
undertakes to perform or to observe only such of its covenants and obligations
as are specifically set forth in this Article Four, and no implied covenants or
obligations with respect to the holders of Senior Indebtedness shall be read
into this Indenture against the Trustee. The Trustee shall not be

                                       30
<PAGE>   38
deemed to owe any fiduciary duty to the holders of Senior Indebtedness and,
subject to the provisions of Section 8.1, the Trustee shall not be liable to any
holder of Senior Indebtedness (i) for any failure to make any payments or
distributions to such holder or (ii) if it shall pay over or deliver to holders
of Notes, the Company or any other Person money in compliance with this Article
Four.

         Section 4.7. No Impairment Of Subordination. No right of any present or
future holder of any Senior Indebtedness to enforce subordination as herein
provided shall at any time in any way be prejudiced or impaired by any act or
failure to act on the part of the Company or by any act or failure to act, in
good faith, by any such holder, or by any noncompliance by the Company with the
terms, provisions and covenants of this Indenture, regardless of any knowledge
thereof which any such holder may have or otherwise be charged with. Senior
Indebtedness may be created, renewed or extended and holders of Senior
Indebtedness may exercise any rights under any instrument creating or evidencing
such Senior Indebtedness, including, without limitation, any waiver of default
thereunder, without any notice to or consent from the holders of the Notes or
the Trustee. No compromise, alteration, amendment, modification, extension,
renewal or other change of, or waiver, consent or other action in respect of,
any liability or obligation under or in respect of the Senior Indebtedness or
any terms or conditions of any instrument creating or evidencing such Senior
Indebtedness shall in any way alter or affect any of the provisions of this
Article Four or the subordination of the Notes provided thereby.

         Section 4.8. Certain Conversions Not Deemed Payment. For the purposes
of this Article Four only, (1) the issuance and delivery of junior securities
upon conversion of Notes in accordance with Article Fifteen shall not be deemed
to constitute a payment or distribution on account of the principal of, premium,
if any, or interest (including Liquidated Damages, if any) on Notes or on
account of the purchase or other acquisition of Notes, and (2) the payment,
issuance or delivery of cash (except in satisfaction of fractional shares
pursuant to Section 15.3), property or securities (other than junior securities)
upon conversion of a Note shall be deemed to constitute payment on account of
the principal of, premium, if any, or interest (including Liquidated Damages, if
any) on such Note. For the purposes of this Section 4.8, the term "junior
securities" means (a) shares of any stock of any class of the Company or (b)
securities of the Company that are subordinated in right of payment to all
Senior Indebtedness that may be outstanding at the time of issuance or delivery
of such securities to substantially the same extent as, or to a greater extent
than, the Notes are so subordinated as provided in this Article Four. Nothing
contained in this Article Four or elsewhere in this Indenture or in the Notes is
intended to or shall impair, as among the Company, its creditors (other than
holders of Senior Indebtedness) and the Noteholders, the right, which is
absolute and unconditional, of the Holder of any Note to convert such Note in
accordance with Article Fifteen.

         Section 4.9. Article Applicable To Paying Agents. If at any time any
paying agent other than the Trustee shall have been appointed by the Company and
be then acting hereunder, the term "Trustee" as used in this Article Four shall
(unless the context otherwise requires) be construed as extending to and
including such paying agent within its meaning as fully for all intents and
purposes as if such paying agent were named in this Article Four in addition to
or in place of the Trustee; provided, however, that the first paragraph of
Section 4.5

                                       31
<PAGE>   39
shall not apply to the Company or any Affiliate of the Company if it or such
Affiliate acts as paying agent.

         The Trustee shall not be responsible for the actions or inactions of
any other paying agents (including the Company if acting as its own paying
agent) and shall have no control of any funds held by such other paying agents.

         Section 4.10. Senior Indebtedness Entitled To Rely. The holders of
Senior Indebtedness (including, without limitation, Designated Senior
Indebtedness) shall have the right to rely upon this Article Four, and no
amendment or modification of the provisions contained herein shall diminish the
rights of such holders unless such holders shall have agreed in writing thereto.

         Section 4.11. Reliance On Judicial Order Or Certificate Of Liquidating
Agent. Upon any payment or distribution of assets of the Company referred to in
this Article Four, the Trustee and the Noteholders shall be entitled to rely
upon any order or decree entered by any court of competent jurisdiction in which
such insolvency, bankruptcy, receivership, liquidation, reorganization,
dissolution, winding up or similar case or proceeding is pending, or a
certificate of the trustee in bankruptcy, liquidating trustee, custodian,
receiver, assignee for the benefit of creditors, agent or other Person making
such payment or distribution, delivered to the Trustee or to the Noteholders,
for the purpose of ascertaining the Persons entitled to participate in such
payment or distribution, the holders of Senior Indebtedness and other
indebtedness of the Company, the amount thereof or payable thereon, the amount
or amounts paid or distributed thereon and all other facts pertinent thereto or
to this Article Four.

                                   ARTICLE 5.

                       PARTICULAR COVENANTS OF THE COMPANY

         Section 5.1. Payment Of Principal, Premium And Interest. The Company
covenants and agrees that it will duly and punctually pay or cause to be paid
the principal of and premium, if any (including the redemption price upon
redemption pursuant to Article Three), and interest (including Liquidated
Damages, if any), on each of the Notes at the places, at the respective times
and in the manner provided herein and in the Notes.

         Section 5.2. Maintenance Of Office Or Agency. The Company will maintain
an office or agency in the Borough of Manhattan, the City of New York, where the
Notes may be surrendered for registration of transfer or exchange or for
presentation for payment or for conversion or redemption and where notices and
demands to or upon the Company in respect of the Notes and this Indenture may be
served. The Company will give prompt written notice to the Trustee of the
location, and any change in the location, of such office or agency not
designated or appointed by the Trustee. If at any time the Company shall fail to
maintain any such required office or agency or shall fail to furnish the Trustee
with the address thereof, such presentations, surrenders, notices and demands
may be made or served at the Corporate Trust Office or the office of agency of
the Trustee in The Borough of Manhattan, The City of New York (which shall
initially be located at United States Trust Company of New York, 114 W. 47th
Street, New

                                       32
<PAGE>   40
York, New York 10036-1532, Attention: Corporate Trust Department (Burr-Brown
Corporation, 4 1/4% Convertible Subordinated Notes due 2007 ).

               The Company may also from time to time designate co-registrars
and one or more offices or agencies where the Notes may be presented or
surrendered for any or all such purposes and may from time to time rescind such
designations. The Company will give prompt written notice of any such
designation or rescission and of any change in the location of any such other
office or agency.

               The Company hereby initially designates the Trustee as paying
agent, Note registrar, Custodian and conversion agent and each of the Corporate
Trust Office and the office of agency of the Trustee in The Borough of
Manhattan, The City of New York (which shall initially be located at United
States Trust Company of New York, 114 W. 47th Street, New York, New York
10036-1532, Attention: Corporate Trust Department (Burr-Brown Corporation, 4
1/4% Convertible Subordinated Notes due 2007 )), shall be considered as one such
office or agency of the Company for each of the aforesaid purposes.

               So long as the Trustee is the Note registrar, the Trustee agrees
to mail, or cause to be mailed, the notices set forth in Section 8.10(a) and the
third paragraph of Section 8.11. If co-registrars have been appointed in
accordance with this Section , the Trustee shall mail such notices only to the
Company and the holders of Notes it can identify from its records.

               Section 5.3. Appointments To Fill Vacancies In Trustee's Office.
The Company, whenever necessary to avoid or fill a vacancy in the office of
Trustee, will appoint, in the manner provided in Section 8.10, a Trustee, so
that there shall at all times be a Trustee hereunder.

               Section 5.4. Provisions As To Paying Agent.

               (a)      If the Company shall appoint a paying agent other than
               the Trustee, or if the Trustee shall appoint such a paying agent,
               the Company will cause such paying agent to execute and deliver
               to the Trustee an instrument in which such agent shall agree with
               the Trustee, subject to the provisions of this Section 5.4:

                        (1)      that it will hold all sums held by it as such
agent for the payment of the principal of and premium, if any, or interest
(including Liquidated Damages, if any) on the Notes (whether such sums have been
paid to it by the Company or by any other obligor on the Notes) in trust for the
benefit of the holders of the Notes;

                        (2)      that it will give the Trustee notice of any
failure by the Company (or by any other obligor on the Notes) to make any
payment of the principal of and premium, if any, or interest on the Notes when
the same shall be due and payable; and

                        (3)      that at any time during the continuance of an
Event of Default, upon request of the Trustee, it will forthwith pay to the
Trustee all sums so held in trust.

               The Company shall, on or before each due date of the principal
of, premium, if any, or interest on the Notes, deposit with the paying agent a
sum (in funds which are

                                       33
<PAGE>   41
immediately available on the due date for such payment) sufficient to pay such
principal, premium, if any, or interest, and (unless such paying agent is the
Trustee) the Company will promptly notify the Trustee of any failure to take
such action; provided, however, that if such deposit is made on the due date,
such deposit shall be received by the paying agent by 10:00 a.m. New York City
time, on such date.

               (b)      If the Company shall act as its own paying agent, it
               will, on or before each due date of the principal of, premium, if
               any, or interest (including Liquidated Damages, if any) on the
               Notes, set aside, segregate and hold in trust for the benefit of
               the holders of the Notes a sum sufficient to pay such principal,
               premium, if any, or interest (including Liquidated Damages, if
               any) so becoming due and will promptly notify the Trustee of any
               failure to take such action and of any failure by the Company (or
               any other obligor under the Notes) to make any payment of the
               principal of, premium, if any, or interest (including Liquidated
               Damages, if any) on the Notes when the same shall become due and
               payable.

               (c)      Anything in this Section 5.4 to the contrary
               notwithstanding, the Company may, at any time, for the purpose of
               obtaining a satisfaction and discharge of this Indenture, or for
               any other reason, pay or cause to be paid to the Trustee all sums
               held in trust by the Company or any paying agent hereunder as
               required by this Section 5.4, such sums to be held by the Trustee
               upon the trusts herein contained and upon such payment by the
               Company or any paying agent to the Trustee, the Company or such
               paying agent shall be released from all further liability with
               respect to such sums.

               (d)      Anything in this Section 5.4 to the contrary
               notwithstanding, the agreement to hold sums in trust as provided
               in this Section 5.4 is subject to Sections 13.3 and 13.4.

               The Trustee shall not be responsible for the actions of any other
paying agents (including the Company if acting as its own paying agent) and
shall have no control of any funds held by such other paying agents.

               Section 5.5. Existence. Subject to Article Twelve, the Company
will do or cause to be done all things necessary to preserve and keep in full
force and effect its existence and rights (charter and statutory); provided,
however, that the Company shall not be required to preserve any such right if
the Company shall determine that the preservation thereof is no longer desirable
in the conduct of the business of the Company and that the loss thereof is not
disadvantageous in any material respect to the Noteholders.

               Section 5.6. Maintenance Of Properties. The Company will cause
all properties used or useful in the conduct of its business or the business of
any Significant Subsidiary to be maintained and kept in good condition, repair
and working order and supplied with all necessary equipment and will cause to be
made all necessary repairs, renewals, replacements, betterments and improvements
thereof, all as in the judgment of the Company may be necessary so that the
business carried on in connection therewith may be properly and advantageously
conducted at all times; provided, however, that nothing in this Section shall
prevent the Company from discontinuing the operation or maintenance of any of
such properties if such discontinuance is, in

                                       34
<PAGE>   42
the judgment of the Company, desirable in the conduct of its business or the
business of any subsidiary and not disadvantageous in any material respect to
the Noteholders.

         Section 5.7. Payment Of Taxes And Other Claims. The Company will pay or
discharge, or cause to be paid or discharged, before the same may become
delinquent, (i) all taxes, assessments and governmental charges levied or
imposed upon the Company or any Significant Subsidiary or upon the income,
profits or property of the Company or any Significant Subsidiary, (ii) all
claims for labor, materials and supplies which, if unpaid, might by law become a
lien or charge upon the property of the Company or any Significant Subsidiary
and (iii) all stamps and other duties, if any, which may be imposed by the
United States or any political subdivision thereof or therein in connection with
the issuance, transfer, exchange or conversion of any Notes or with respect to
this Indenture; provided, however, that, in the case of clauses (i) and (ii),
the Company shall not be required to pay or discharge or cause to be paid or
discharged any such tax, assessment, charge or claim (A) if the failure to do so
will not, in the aggregate, have a material adverse impact on the Company, or
(B) if the amount, applicability or validity is being contested in good faith by
appropriate proceedings.

         Section 5.8. Rule 144A Information Requirement. Within the period prior
to the expiration of the holding period applicable to sales thereof under Rule
144(k) under the Securities Act (or any successor provision), the Company
covenants and agrees that it shall, during any period in which it is not subject
to Section 13 or 15(d) under the Exchange Act, make available to any holder or
beneficial holder of Notes or any Common Stock issued upon conversion thereof
which continue to be Restricted Securities in connection with any sale thereof
and any prospective purchaser of Notes or such Common Stock designated by such
holder or beneficial holder, the information required pursuant to Rule
144A(d)(4) under the Securities Act upon the request of any holder or beneficial
holder of the Notes or such Common Stock and it will take such further action as
any holder or beneficial holder of such Notes or such Common Stock may
reasonably request, all to the extent required from time to time to enable such
holder or beneficial holder to sell its Notes or Common Stock without
registration under the Securities Act within the limitation of the exemption
provided by Rule 144A, as such Rule may be amended from time to time. Upon the
request of any holder or any beneficial holder of the Notes or such Common
Stock, the Company will deliver to such holder a written statement as to whether
it has complied with such requirements.

         Section 5.9. Stay, Extension And Usury Laws. The Company covenants (to
the extent that it may lawfully do so) that it shall not at any time insist
upon, plead, or in any manner whatsoever claim or take the benefit or advantage
of, any stay, extension or usury law or other law which would prohibit or
forgive the Company from paying all or any portion of the principal of, premium,
if any, or interest (including Liquidated Damages, if any) on the Notes as
contemplated herein, wherever enacted, now or at any time hereafter in force, or
which may affect the covenants or the performance of this Indenture and the
Company (to the extent it may lawfully do so) hereby expressly waives all
benefit or advantage of any such law, and covenants that it will not, by resort
to any such law, hinder, delay or impede the execution of any power herein
granted to the Trustee, but will suffer and permit the execution of every such
power as though no such law had been enacted.

                                       35
<PAGE>   43
         Section 5.10. Compliance Certificate. The Company shall deliver to the
Trustee, within one hundred twenty (120) days after the end of each fiscal year
of the Company, a certificate signed by either the principal executive officer,
principal financial officer or principal accounting officer of the Company,
stating whether or not to the best knowledge of the signer thereof the Company
is in default in the performance and observance of any of the terms, provisions
and conditions of this Indenture (without regard to any period of grace or
requirement of notice provided hereunder) and, if the Company shall be in
default, specifying all such defaults and the nature and the status thereof of
which the signer may have knowledge.

         The Company will deliver to the Trustee, forthwith upon becoming aware
of (i) any default in the performance or observance of any covenant, agreement
or condition contained in this Indenture, or (ii) any Event of Default, an
Officers' Certificate specifying with particularity such default or Event of
Default and further stating what action the Company has taken, is taking or
proposes to take with respect thereto.

                  Any notice required to be given under this Section 5.10 or
Section 4.5 shall be delivered to a Responsible Officer of the Trustee at its
Corporate Trust Office. In the event that the payment of the Notes is
accelerated because of an Event of Default, the Company shall promptly provide
written notice to the Trustee specifying the names and addresses of the holders
of Senior Indebtedness if the Trustee (and not the Company) is to provide
holders of Senior Indebtedness notice of such acceleration under Section 4.5 of
the Indenture.

         Section 5.11. Liquidated Damages Notice. In the event that the Company
is required to pay Liquidated Damages to holders of Notes pursuant to the
Registration Rights Agreement, the Company will provide written notice
("Liquidated Damages Notice") to the Trustee of its obligation to pay Liquidated
Damages no later than fifteen days prior to the proposed payment date for the
Liquidated Damages, and the Liquidated Damages Notice shall set forth the amount
of Liquidated Damages to be paid by the Company on such payment date. The
Trustee shall not at any time be under any duty or responsibility to any holder
of Notes to determine the Liquidated Damages, or with respect to the nature,
extent or calculation of the amount of Liquidated Damages when made, or with
respect to the method employed in such calculation of the Liquidated Damages.

                                   ARTICLE 6.

                         NOTEHOLDERS' LISTS AND REPORTS
                         BY THE COMPANY AND THE TRUSTEE

         Section 6.1. Noteholders' Lists. The Company covenants and agrees that
it will furnish or cause to be furnished to the Trustee, semiannually, not more
than fifteen (15) days after each February 1 and August 1 in each year beginning
with August 1, 2000, and at such other times as the Trustee may request in
writing, within thirty (30) days after receipt by the Company of any such
request (or such lesser time as the Trustee may reasonably request in order to
enable it to timely provide any notice to be provided by it hereunder), a list
in such form as the Trustee may reasonably require of the names and addresses of
the holders of Notes as of a date not more than fifteen (15) days (or such other
date as the Trustee may reasonably request in order to so provide any such
notices) prior to the time such information is furnished, except that

                                       36
<PAGE>   44
no such list need be furnished by the Company to the Trustee so long as the
Trustee is acting as the sole Note registrar.

               Section 6.2. Preservation And Disclosure Of Lists.

               (a)      The Trustee shall preserve, in as current a form as is
               reasonably practicable, all information as to the names and
               addresses of the holders of Notes contained in the most recent
               list furnished to it as provided in Section 6.1 or maintained by
               the Trustee in its capacity as Note registrar or co-registrar in
               respect of the Notes, if so acting. The Trustee may destroy any
               list furnished to it as provided in Section 6.1 upon receipt of a
               new list so furnished.

               (b)      The rights of Noteholders to communicate with other
               holders of Notes with respect to their rights under this
               Indenture or under the Notes, and the corresponding rights and
               duties of the Trustee, shall be as provided by the Trust
               Indenture Act.

               (c)      Every Noteholder, by receiving and holding the same,
               agrees with the Company and the Trustee that neither the Company
               nor the Trustee nor any agent of either of them shall be held
               accountable by reason of any disclosure of information as to
               names and addresses of holders of Notes made pursuant to the
               Trust Indenture Act.

               Section  6.3. Reports By Trustee.

               (a)      Within sixty (60) days after February 1 of each year
               commencing with the year 2001, the Trustee shall transmit to
               holders of Notes such reports dated as of February 1 of the year
               in which such reports are made concerning the Trustee and its
               actions under this Indenture as may be required pursuant to the
               Trust Indenture Act at the times and in the manner provided
               pursuant thereto.

               (b)      A copy of such report shall, at the time of such
               transmission to holders of Notes, be filed by the Trustee with
               each stock exchange and automated quotation system upon which the
               Notes are listed and with the Company. The Company will promptly
               notify the Trustee in writing when the Notes are listed on any
               stock exchange or automated quotation system or delisted
               therefrom.

               Section 6.4. Reports By Company. The Company shall file with the
Trustee (and the Commission if at any time after the Indenture becomes qualified
under the Trust Indenture Act such filing is required), and transmit to holders
of Notes, such information, documents and other reports and such summaries
thereof, as may be required pursuant to the Trust Indenture Act at the times and
in the manner provided pursuant to such Act, whether or not the Notes are
governed by such Act; provided, however, that any such information, documents or
reports required to be filed with the Commission pursuant to Section 13 or 15(d)
of the Exchange Act shall be filed with the Trustee within fifteen (15) days
after the same is so required to be filed with the Commission. Delivery of such
reports, information and documents to the Trustee is for informational purposes
only and the Trustee's receipt of such shall not constitute constructive notice
of any information contained therein or determinable from information contained
therein, including the Company's compliance with any of its covenants hereunder
(as to which the Trustee is entitled to rely exclusively on Officers'
Certificates).

                                       37
<PAGE>   45
                                   ARTICLE 7.

                           REMEDIES OF THE TRUSTEE AND
                       NOTEHOLDERS ON AN EVENT OF DEFAULT

               Section 7.1. Events Of Default. In case one or more of the
following Events of Default (whatever the reason for such Event of Default and
whether it shall be voluntary or involuntary or be effected by operation of law
or pursuant to any judgment, decree or order of any court or any order, rule or
regulation of any administrative or governmental body) shall have occurred and
be continuing:

               (a)      default in the payment of any installment of interest
               (including Liquidated Damages, if any) upon any of the Notes as
               and when the same shall become due and payable, and continuance
               of such default for a period of thirty (30) days, whether or not
               such payment is permitted under Article Four hereof; or

               (b)      default in the payment of the principal of or premium,
               if any, on any of the Notes as and when the same shall become due
               and payable either at maturity or in connection with any
               redemption pursuant to Article Three, by acceleration or
               otherwise, whether or not such payment is permitted under Article
               Four hereof; or

               (c)      failure on the part of the Company duly to observe or
               perform any other of the covenants or agreements on the part of
               the Company in the Notes or in this Indenture (other than a
               covenant or agreement a default in whose performance or whose
               breach is elsewhere in this Section 7.1 specifically dealt with)
               continued for a period of sixty (60) days after the date on which
               written notice of such failure, requiring the Company to remedy
               the same, shall have been given to the Company by the Trustee, or
               the Company and a Responsible Officer of the Trustee by the
               holders of at least twenty-five percent (25%) in aggregate
               principal amount of the Notes at the time outstanding determined
               in accordance with Section 9.4; or

               (d)      the Company shall commence a voluntary case or other
               proceeding seeking liquidation, reorganization or other relief
               with respect to the Company or its debts under any bankruptcy,
               insolvency or other similar law now or hereafter in effect or
               seeking the appointment of a trustee, receiver, liquidator,
               custodian or other similar official of the Company or any
               substantial part of the property of the Company, or shall consent
               to any such relief or to the appointment of or taking possession
               by any such official in an involuntary case or other proceeding
               commenced against the Company, or shall make a general assignment
               for the benefit of creditors, or shall fail generally to pay its
               debts as they become due; or

               (e)      an involuntary case or other proceeding shall be
               commenced against the Company seeking liquidation, reorganization
               or other relief with respect to the Company or its debts under
               any bankruptcy, insolvency or other similar law now or hereafter
               in effect or seeking the appointment of a trustee, receiver,
               liquidator, custodian or other similar official of the Company or
               any substantial part of the property of the Company,

                                       38
<PAGE>   46
         and such involuntary case or other proceeding shall remain undismissed
         and unstayed for a period of ninety (90) consecutive days;

then, and in each and every such case (other than an Event of Default specified
in Section 7.1(d) or (e)), unless the principal of all of the Notes shall have
already become due and payable, either the Trustee or the holders of not less
than twenty-five percent (25%) in aggregate principal amount of the Notes then
outstanding hereunder determined in accordance with Section 9.4, by notice in
writing to the Company (and to the Trustee if given by Noteholders), may declare
the principal of and premium, if any, on all the Notes and the interest accrued
thereon (including Liquidated Damages, if any) to be due and payable
immediately, and upon any such declaration the same shall become and shall be
immediately due and payable, anything in this Indenture or in the Notes
contained to the contrary notwithstanding. If an Event of Default specified in
Section 7.1(d) or (e) occurs, the principal of all the Notes and the interest
accrued thereon shall (including Liquidated Damages, if any) be immediately and
automatically due and payable without necessity of further action. This
provision, however, is subject to the conditions that if, at any time after the
principal of the Notes shall have been so declared due and payable, and before
any judgment or decree for the payment of the monies due shall have been
obtained or entered as hereinafter provided, the Company shall pay or shall
deposit with the Trustee a sum sufficient to pay all matured installments of
interest upon (including Liquidated Damages, if any) all Notes and the principal
of and premium, if any, on any and all Notes which shall have become due
otherwise than by acceleration (with interest on overdue installments of
interest (including Liquidated Damages, if any) (to the extent that payment of
such interest is enforceable under applicable law) and on such principal and
premium, if any, at the rate borne by the Notes, to the date of such payment or
deposit) and amounts due to the Trustee pursuant to Section 8.6, and if any and
all defaults under this Indenture, other than the nonpayment of principal of and
premium, if any, and accrued interest on (including Liquidated Damages, if any)
Notes which shall have become due by acceleration, shall have been cured or
waived pursuant to Section 7.7, then and in every such case the holders of a
majority in aggregate principal amount of the Notes then outstanding, by written
notice to the Company and to the Trustee, may waive all defaults or Events of
Default and rescind and annul such declaration and its consequences; but no such
waiver or rescission and annulment shall extend to or shall affect any
subsequent default or Event of Default, or shall impair any right consequent
thereon. The Company shall notify a Responsible Officer of the Trustee, promptly
upon becoming aware thereof, of any Event of Default.

         In case the Trustee shall have proceeded to enforce any right under
this Indenture and such proceedings shall have been discontinued or abandoned
because of such waiver or rescission and annulment or for any other reason or
shall have been determined adversely to the Trustee, then and in every such case
the Company, the holders of Notes, and the Trustee shall be restored
respectively to their several positions and rights hereunder, and all rights,
remedies and powers of the Company, the holders of Notes, and the Trustee shall
continue as though no such proceeding had been taken.

         Section 7.2. Payments Of Notes On Default; Suit Therefor. The Company
covenants that (a) in case default shall be made in the payment of any
installment of interest upon (including Liquidated Damages, if any) any of the
Notes as and when the same shall become due and payable, and such default shall
have continued for a period of thirty (30) days,

                                       39
<PAGE>   47
or (b) in case default shall be made in the payment of the principal of or
premium, if any, on any of the Notes as and when the same shall have become due
and payable, whether at maturity of the Notes or in connection with any
redemption, by or under this Indenture declaration or otherwise, then, upon
demand of the Trustee, the Company will pay to the Trustee, for the benefit of
the holders of the Notes, the whole amount that then shall have become due and
payable on all such Notes for principal and premium, if any, or interest
(including Liquidated Damages, if any), as the case may be, with interest upon
the overdue principal and premium, if any, and (to the extent that payment of
such interest is enforceable under applicable law) upon the overdue installments
of interest (including Liquidated Damages, if any) at the rate borne by the
Notes, and, in addition thereto, such further amount as shall be sufficient to
cover the costs and expenses of collection, including reasonable compensation to
the Trustee, its agents, attorneys and counsel, and all other amounts due the
Trustee under Section 8.6. Until such demand by the Trustee, the Company may pay
the principal of and premium, if any, and interest on (including Liquidated
Damages, if any) the Notes to the registered holders, whether or not the Notes
are overdue.

         In case the Company shall fail forthwith to pay such amounts upon such
demand, the Trustee, in its own name and as trustee of an express trust, shall
be entitled and empowered to institute any actions or proceedings at law or in
equity for the collection of the sums so due and unpaid, and may prosecute any
such action or proceeding to judgment or final decree, and may enforce any such
judgment or final decree against the Company or any other obligor on the Notes
and collect in the manner provided by law out of the property of the Company or
any other obligor on the Notes wherever situated the monies adjudged or decreed
to be payable.

         In case:

         (i) there shall be pending proceedings for the bankruptcy or for the
reorganization of the Company or any other obligor on the Notes under Title 11
of the United States Code, or any other applicable law;

         (ii) a receiver, assignee or trustee in bankruptcy or reorganization,
liquidator, sequestrator or similar official shall have been appointed for, or
taken possession of, the Company, such other obligor, or the property of the
Company or such other obligor, or

         (iii) there shall be pending any other judicial proceedings relative to
the Company, such other obligor upon the Notes, or to the creditors or property
of the Company or such other obligor,

the Trustee, irrespective of whether the principal of the Notes shall then be
due and payable as therein expressed or by declaration or otherwise and
irrespective of whether the Trustee shall have made any demand pursuant to the
provisions of this Section 7.2, shall be entitled and empowered, by intervention
in such proceedings or otherwise, to file and prove a claim or claims for the
whole amount of principal, premium, if any, and interest (including Liquidated
Damages, if any) owing and unpaid in respect of the Notes, and, in case of any
judicial proceedings, to file such proofs of claim and other papers or documents
as may be necessary or advisable in order to have the claims of the Trustee and
of the Noteholders allowed in such judicial proceedings relative to the Company
or any other obligor on the Notes, its or their creditors, or its or their

                                       40
<PAGE>   48
property, and to collect and receive any monies or other property payable or
deliverable upon the conversion or exchange of the Notes or upon any such
claims, and to distribute the same after the deduction of any amounts due the
Trustee under Section 8.6, and any receiver, assignee or trustee in bankruptcy
or reorganization, liquidator, custodian or similar official is hereby
authorized by each of the Noteholders to make such payments to the Trustee, and,
in the event that the Trustee shall consent to the making of such payments
directly to the Noteholders, to pay to the Trustee any amount due it for
reasonable compensation, expenses, advances and disbursements, including counsel
fees incurred by it up to the date of such distribution. To the extent that such
payment of reasonable compensation, expenses, advances and disbursements out of
the estate in any such proceedings shall be denied for any reason, payment of
the same shall be secured by a lien on, and shall be paid out of, any and all
distributions, dividends, monies, securities and other property which the
holders of the Notes may be entitled to receive in such proceedings, whether in
liquidation or under any plan of reorganization or arrangement or otherwise.

         All rights of action and of asserting claims under this Indenture, or
under any of the Notes, may be enforced by the Trustee without the possession of
any of the Notes, or the production thereof at any trial or other proceeding
relative thereto, and any such suit or proceeding instituted by the Trustee
shall be brought in its own name as trustee of an express trust, and any
recovery of judgment shall, after provision for the payment of the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agent and
counsel, be for the ratable benefit of the holders of the Notes.

         In any proceedings brought by the Trustee (and in any proceedings
involving the interpretation of any provision of this Indenture to which the
Trustee shall be a party) the Trustee shall be held to represent all the holders
of the Notes, and it shall not be necessary to make any holders of the Notes
parties to any such proceedings.

         Section 7.3. Application Of Monies Collected By Trustee. Any monies
collected by the Trustee pursuant to this Article Seven shall be applied in the
order following, at the date or dates fixed by the Trustee for the distribution
of such monies, upon presentation of the several Notes, and stamping thereon the
payment, if only partially paid, and upon surrender thereof, if fully paid:

         FIRST: To the payment of all amounts due the Trustee under Section 8.6;

         SECOND: Subject to the provisions of Article Four, in case the
principal of the outstanding Notes shall not have become due and be unpaid, to
the payment of interest on (including Liquidated Damages, if any) the Notes in
default in the order of the maturity of the installments of such interest, with
interest (to the extent that such interest has been collected by the Trustee)
upon the overdue installments of interest (including Liquidated Damages, if any)
at the rate borne by the Notes, such payments to be made ratably to the Persons
entitled thereto;

         THIRD: Subject to the provisions of Article Four, in case the principal
of the outstanding Notes shall have become due, by declaration or otherwise, and
be unpaid to the payment of the whole amount then owing and unpaid upon the
Notes for principal and premium, if any, and interest (including Liquidated
Damages, if any), with interest on the overdue principal

                                       41
<PAGE>   49
and premium, if any, and (to the extent that such interest has been collected by
the Trustee) upon overdue installments of interest (including Liquidated
Damages, if any) at the rate borne by the Notes, and in case such monies shall
be insufficient to pay in full the whole amounts so due and unpaid upon the
Notes, then to the payment of such principal and premium, if any, and interest
(including Liquidated Damages, if any) without preference or priority of
principal and premium, if any, over interest (including Liquidated Damages, if
any), or of interest (including Liquidated Damages, if any) over principal and
premium, if any, or of any installment of interest over any other installment of
interest, or of any Note over any other Note, ratably to the aggregate of such
principal and premium, if any, and accrued and unpaid interest; and

         FOURTH: Subject to the provisions of Article Four, to the payment of
the remainder, if any, to the Company or any other Person lawfully entitled
thereto.

         Section 7.4. Proceedings By Noteholder. No holder of any Note shall
have any right by virtue of or by reference to any provision of this Indenture
to institute any suit, action or proceeding in equity or at law upon or under or
with respect to this Indenture, or for the appointment of a receiver, trustee,
liquidator, custodian or other similar official, or for any other remedy
hereunder, unless such holder previously shall have given to the Trustee written
notice of an Event of Default and of the continuance thereof, as hereinbefore
provided, and unless also the holders of not less than twenty-five percent (25%)
in aggregate principal amount of the Notes then outstanding shall have made
written request upon the Trustee to institute such action, suit or proceeding in
its own name as Trustee hereunder and shall have offered to the Trustee such
reasonable indemnity satisfactory to the Trustee against any costs, expenses and
liabilities to be incurred therein or thereby, and the Trustee for sixty (60)
days after its receipt of such notice, request and offer of indemnity, shall
have neglected or refused to institute any such action, suit or proceeding and
no direction inconsistent with such written request shall have been given to the
Trustee pursuant to Section 7.7; it being understood and intended, and being
expressly covenanted by the taker and holder of every Note with every other
taker and holder and the Trustee, that no one or more holders of Notes shall
have any right in any manner whatever by virtue of or by reference to any
provision of this Indenture to affect, disturb or prejudice the rights of any
other holder of Notes, or to obtain or seek to obtain priority over or
preference to any other such holder, or to enforce any right under this
Indenture, except in the manner herein provided and for the equal, ratable and
common benefit of all holders of Notes (except as otherwise provided herein).
For the protection and enforcement of this Section 7.4, each and every
Noteholder and the Trustee shall be entitled to such relief as can be given
either at law or in equity.

         Notwithstanding any other provision of this Indenture and any provision
of any Note, the right of any holder of any Note to receive payment of the
principal of and premium, if any (including the redemption price upon redemption
pursuant to Article Three), and accrued interest on (including Liquidated
Damages, if any) such Note, on or after the respective due dates expressed in
such Note or in the event of redemption, or to institute suit for the
enforcement of any such payment on or after such respective dates against the
Company shall not be impaired or affected without the consent of such holder.

         Anything in this Indenture or the Notes to the contrary
notwithstanding, the holder of any Note, without the consent of either the
Trustee or the holder of any other Note, in

                                       42
<PAGE>   50
its own behalf and for its own benefit, may enforce, and may institute and
maintain any proceeding suitable to enforce, its rights of conversion as
provided herein.

         Section 7.5. Proceedings By Trustee. In case of an Event of Default
known to a Responsible Officer of the Trustee, the Trustee may, in its
discretion, proceed to protect and enforce the rights vested in it by this
Indenture by such appropriate judicial proceedings as are necessary to protect
and enforce any of such rights, either by suit in equity or by action at law or
by proceeding in bankruptcy or otherwise, whether for the specific enforcement
of any covenant or agreement contained in this Indenture or in aid of the
exercise of any power granted in this Indenture, or to enforce any other legal
or equitable right vested in the Trustee by this Indenture or by law.

         Section 7.6. Remedies Cumulative And Continuing. Except as provided in
Section 2.6, all powers and remedies given by this Article Seven to the Trustee
or to the Noteholders shall, to the extent permitted by law, be deemed
cumulative and not exclusive of any thereof or of any other powers and remedies
available to the Trustee or the holders of the Notes, by judicial proceedings or
otherwise, to enforce the performance or observance of the covenants and
agreements contained in this Indenture, and no delay or omission of the Trustee
or of any holder of any of the Notes to exercise any right or power accruing
upon any default or Event of Default occurring and continuing as aforesaid shall
impair any such right or power, or shall be construed to be a waiver of any such
default or any acquiescence therein, and, subject to the provisions of Section
7.4, every power and remedy given by this Article Seven or by law to the Trustee
or to the Noteholders may be exercised from time to time, and as often as shall
be deemed expedient, by the Trustee or by the Noteholders.

         Section 7.7. Direction Of Proceedings And Waiver Of Defaults By
Majority Of Noteholders. The holders of a majority in aggregate principal amount
of the Notes at the time outstanding determined in accordance with Section 9.4
shall have the right to direct the time, method and place of conducting any
proceeding for any remedy available to the Trustee or exercising any trust or
power conferred on the Trustee; provided, however, that (a) such direction shall
not be in conflict with any rule of law or with this Indenture, (b) the Trustee
may take any other action which is not inconsistent with such direction and (c)
the Trustee may decline to take any action that would benefit some Noteholder to
the detriment of other Noteholders. The holders of a majority in aggregate
principal amount of the Notes at the time outstanding determined in accordance
with Section 9.4 may, on behalf of the holders of all of the Notes, waive any
past default or Event of Default hereunder and its consequences except (i) a
default in the payment of interest (including Liquidated Damages, if any) or
premium, if any, on, or the principal of, the Notes, (ii) a failure by the
Company to convert any Notes into Common Stock, (iii) a default in the payment
of redemption price pursuant to Article Three or (iv) a default in respect of a
covenant or provisions hereof which under Article Eleven cannot be modified or
amended without the consent of the holders of each or all Notes then outstanding
or affected thereby. Upon any such waiver, the Company, the Trustee and the
holders of the Notes shall be restored to their former positions and rights
hereunder; but no such waiver shall extend to any subsequent or other default or
Event of Default or impair any right consequent thereon. Whenever any default or
Event of Default hereunder shall have been waived as permitted by this Section
7.7, said default or Event of Default shall for all purposes of the Notes and
this Indenture

                                       43
<PAGE>   51
be deemed to have been cured and to be not continuing; but no such waiver shall
extend to any subsequent or other default or Event of Default or impair any
right consequent thereon.

         Section 7.8. Notice Of Defaults. The Trustee shall, within ninety (90)
days after a Responsible Officer of the Trustee has knowledge of the occurrence
of a default, mail to all Noteholders, as the names and addresses of such
holders appear upon the Note register, notice of all defaults known to a
Responsible Officer, unless such defaults shall have been cured or waived before
the giving of such notice; provided, however, that except in the case of default
in the payment of the principal of, or premium, if any, or interest (including
Liquidated Damages, if any) on any of the Notes, the Trustee shall be protected
in withholding such notice if and so long as a trust committee of directors
and/or Responsible Officers of the Trustee in good faith determines that the
withholding of such notice is in the interests of the Noteholders.

         Section 7.9. Undertaking To Pay Costs. All parties to this Indenture
agree, and each holder of any Note by his acceptance thereof shall be deemed to
have agreed, that any court may, in its discretion, require, in any suit for the
enforcement of any right or remedy under this Indenture, or in any suit against
the Trustee for any action taken or omitted by it as Trustee, the filing by any
party litigant in such suit of an undertaking to pay the costs of such suit and
that such court may in its discretion assess reasonable costs, including
reasonable attorneys' fees and expenses, against any party litigant in such
suit, having due regard to the merits and good faith of the claims or defenses
made by such party litigant; provided, however, that the provisions of this
Section 7.9 (to the extent permitted by law) shall not apply to any suit
instituted by the Trustee, to any suit instituted by any Noteholder, or group of
Noteholders, holding in the aggregate more than ten percent in principal amount
of the Notes at the time outstanding determined in accordance with Section 9.4,
or to any suit instituted by any Noteholder for the enforcement of the payment
of the principal of or premium, if any, or interest on any Note on or after the
due date expressed in such Note or to any suit for the enforcement of the right
to convert any Note in accordance with the provisions of Article Fifteen.

                                   ARTICLE 8.

                                   THE TRUSTEE

         Section 8.1. Duties And Responsibilities Of Trustee. The Trustee, prior
to the occurrence of an Event of Default and after the curing of all Events of
Default which may have occurred, undertakes to perform such duties and only such
duties as are specifically set forth in this Indenture. In case an Event of
Default has occurred (which has not been cured or waived), the Trustee shall
exercise such of the rights and powers vested in it by this Indenture, and use
the same degree of care and skill in their exercise, as a prudent person would
exercise or use under the circumstances in the conduct of his own affairs.

         No provision of this Indenture shall be construed to relieve the
Trustee from liability for its own negligent action, its own negligent failure
to act or its own willful misconduct, except that:

         (a)      prior to the occurrence of an Event of Default and after the
         curing or waiving of all Events of Default which may have occurred:

                                       44
<PAGE>   52
                  (1)      the duties and obligations of the Trustee shall be
determined solely by the express provisions of this Indenture and the Trust
Indenture Act, and the Trustee shall not be liable except for the performance of
such duties and obligations as are specifically set forth in this Indenture and
no implied covenants or obligations shall be read into this Indenture and the
Trust Indenture Act against the Trustee; and

                  (2)      in the absence of bad faith and willful misconduct on
the part of the Trustee, the Trustee may conclusively rely as to the truth of
the statements and the correctness of the opinions expressed therein, upon any
certificates or opinions furnished to the Trustee and conforming to the
requirements of this Indenture; but, in the case of any such certificates or
opinions which by any provisions hereof are specifically required to be
furnished to the Trustee, the Trustee shall be under a duty to examine the same
to determine whether or not they conform to the requirements of this Indenture;

         (b)      the Trustee shall not be liable for any error of judgment made
         in good faith by a Responsible Officer or Officers of the Trustee,
         unless it is proved that the Trustee was negligent in ascertaining the
         pertinent facts;

         (c)      the Trustee shall not be liable with respect to any action
         taken or omitted to be taken by it in good faith in accordance with the
         written direction of the holders of not less than a majority in
         principal amount of the Notes at the time outstanding determined as
         provided in Section 9.4 relating to the time, method and place of
         conducting any proceeding for any remedy available to the Trustee, or
         exercising any trust or power conferred upon the Trustee, under this
         Indenture;

         (d)      whether or not therein provided, every provision of this
         Indenture relating to the conduct or affecting the liability of, or
         affording protection to, the Trustee shall be subject to the provisions
         of this Section;

         (e)      the Trustee shall not be liable in respect of any payment (as
         to the correctness of amount, entitlement to receive or any other
         matters relating to payment) or notice effected by the Company or any
         paying agent or any records maintained by any co-registrar with respect
         to the Notes; and

         (f)      if any party fails to deliver a notice relating to an event
         the fact of which, pursuant to this Indenture, requires notice to be
         sent to the Trustee, the Trustee may conclusively rely on its failure
         to receive such notice as reason to act as if no such event occurred.

         None of the provisions contained in this Indenture shall require the
Trustee to expend or risk its own funds or otherwise incur any financial
liability in the performance of any of its duties hereunder or in the exercise
of any of its rights or powers, if there is reasonable ground for believing that
the repayment of such funds or adequate indemnity against such risk or liability
is not reasonably assured to it.

                                       45
<PAGE>   53
         Section 8.2. Reliance On Documents, Opinions, Etc. Except as otherwise
provided in Section 8.1:

         (a)      the Trustee may rely and shall be protected in acting upon any
         resolution, certificate, statement, instrument, opinion, report,
         notice, request, consent, order, bond, debenture, note, coupon or other
         paper or document (whether in its original or facsimile form) believed
         by it in good faith to be genuine and to have been signed or presented
         by the proper party or parties;

         (b)      any request, direction, order or demand of the Company
         mentioned herein shall be sufficiently evidenced by an Officers'
         Certificate (unless other evidence in respect thereof be herein
         specifically prescribed); and any resolution of the Board of Directors
         may be evidenced to the Trustee by a copy thereof certified by the
         Secretary or an Assistant Secretary of the Company;

         (c)      the Trustee may consult with counsel of its own selection and
         any advice or Opinion of Counsel shall be full and complete
         authorization and protection in respect of any action taken or omitted
         by it hereunder in good faith and in accordance with such advice or
         Opinion of Counsel;

         (d)      the Trustee shall be under no obligation to exercise any of
         the rights or powers vested in it by this Indenture at the request,
         order or direction of any of the Noteholders pursuant to the provisions
         of this Indenture, unless such Noteholders shall have offered to the
         Trustee reasonable security or indemnity against the costs, expenses
         and liabilities which may be incurred therein or thereby;

         (e)      the Trustee shall not be bound to make any investigation into
         the facts or matters stated in any resolution, certificate, statement,
         instrument, opinion, report, notice, request, direction, consent,
         order, bond, debenture or other paper or document, but the Trustee, in
         its discretion, may make such further inquiry or investigation into
         such facts or matters as it may see fit, and, if the Trustee shall
         determine to make such further inquiry or investigation, it shall be
         entitled to examine the books, records and premises of the Company,
         personally or by agent or attorney; and

         (f)      the Trustee may execute any of the trusts or powers hereunder
         or perform any duties hereunder either directly or by or through agents
         or attorneys and the Trustee shall not be responsible for any
         misconduct or negligence on the part of any agent or attorney appointed
         by it with due care hereunder.

         Section 8.3. No Responsibility For Recitals, Etc. The recitals
contained herein and in the Notes (except in the Trustee's certificate of
authentication) shall be taken as the statements of the Company, and the Trustee
assumes no responsibility for the correctness of the same. The Trustee makes no
representations as to the validity or sufficiency of this Indenture or of the
Notes. The Trustee shall not be accountable for the use or application by the
Company of any Notes or the proceeds of any Notes authenticated and delivered by
the Trustee in conformity with the provisions of this Indenture.

                                       46
<PAGE>   54
         Section 8.4. Trustee, Paying Agents, Conversion Agents Or Registrar May
Own Notes. The Trustee, any paying agent, any conversion agent or Note
registrar, in its individual or any other capacity, may become the owner or
pledgee of Notes with the same rights it would have if it were not Trustee,
paying agent, conversion agent or Note registrar.

         Section 8.5. Monies To Be Held In Trust. Subject to the provisions of
Section 13.4 and Section 4.2, all monies received by the Trustee shall, until
used or applied as herein provided, be held in trust for the purposes for which
they were received. Money held by the Trustee in trust hereunder need not be
segregated from other funds except to the extent required by law. The Trustee
shall be under no liability for interest on any money received by it hereunder
except as may be agreed in writing from time to time by the Company and the
Trustee.

         Section 8.6. Compensation And Expenses Of Trustee. The Company
covenants and agrees to pay to the Trustee from time to time, and the Trustee
shall be entitled to, reasonable compensation for all services rendered by it
hereunder in any capacity (which shall not be limited by any provision of law in
regard to the compensation of a trustee of an express trust) as mutually agreed
to from time to time in writing between the Company and the Trustee, and the
Company will pay or reimburse the Trustee upon its request for all reasonable
expenses, disbursements and advances reasonably incurred or made by the Trustee
in accordance with any of the provisions of this Indenture (including the
reasonable compensation and the expenses and disbursements of its counsel and of
all Persons not regularly in its employ) except any such expense, disbursement
or advance as may arise from its negligence, willful misconduct, recklessness or
bad faith. The Company also covenants to indemnify the Trustee (or any officer,
director or employee of the Trustee), in any capacity under this Indenture and
its agents and any authenticating agent for, and to hold them harmless against,
any and all loss, liability, claim or expense incurred without negligence,
willful misconduct, recklessness or bad faith on the part of the Trustee or such
officers, directors, employees and agent or authenticating agent, as the case
may be, and arising out of or in connection with the acceptance or
administration of this trust or in any other capacity hereunder, including the
costs and expenses of enforcing this Indenture against the Company (including
Section 8.6) and of defending themselves against any claim (whether asserted by
any Noteholder or the Company) of liability in the premises. The obligations of
the Company under this Section 8.6 to compensate or indemnify the Trustee and to
pay or reimburse the Trustee for expenses, disbursements and advances shall be
secured by a lien prior to that of the Notes upon all property and funds held or
collected by the Trustee as such, except funds held in trust for the benefit of
the holders of particular Notes. The Trustee's right to receive payment of any
amounts due under this Section 8.6 shall not be subordinate to any other
liability or indebtedness of the Company (even though the Notes may be so
subordinated). The obligation of the Company under this Section shall survive
the satisfaction and discharge of this Indenture.

         When the Trustee and its agents and any authenticating agent incur
expenses or render services after an Event of Default specified in Section
7.1(d) or (e) with respect to the Company occurs, the expenses and the
compensation for the services are intended to constitute expenses of
administration under any bankruptcy, insolvency or similar laws.

         Section 8.7. Officers' Certificate As Evidence. Except as otherwise
provided in Section 8.1, whenever in the administration of the provisions of
this Indenture the Trustee shall

                                       47
<PAGE>   55
deem it necessary or desirable that a matter be proved or established prior to
taking or omitting any action hereunder, such matter (unless other evidence in
respect thereof be herein specifically prescribed) may, in the absence of
negligence or willful misconduct on the part of the Trustee, be deemed to be
conclusively proved and established by an Officers' Certificate delivered to the
Trustee.

         Section 8.8. Conflicting Interests Of Trustee. If the Trustee has or
shall acquire a conflicting interest within the meaning of the Trust Indenture
Act, the Trustee shall either eliminate such interest or resign, to the extent
and in the manner provided by, and subject to the provisions of, the Trust
Indenture Act and this Indenture.

         Section 8.9. Eligibility Of Trustee. There shall at all times be a
Trustee hereunder which shall be a Person that is eligible pursuant to the Trust
Indenture Act to act as such and has a combined capital and surplus of at least
$50,000,000 (or if such Person is a member of a bank holding company system, its
bank holding company shall have a combined capital and surplus of at least
$50,000,000). If such Person publishes reports of condition at least annually,
pursuant to law or to the requirements of any supervising or examining
authority, then for the purposes of this Section the combined capital and
surplus of such Person shall be deemed to be its combined capital and surplus as
set forth in its most recent report of condition so published. If at any time
the Trustee shall cease to be eligible in accordance with the provisions of this
Section 8.9, it shall resign immediately in the manner and with the effect
hereinafter specified in this Article.

         Section 8.10. Resignation or Removal Of Trustee.

         (a)      The Trustee may at any time resign by giving written notice of
         such resignation to the Company and to the holders of Notes. Upon
         receiving such notice of resignation, the Company shall promptly
         appoint a successor trustee by written instrument, in duplicate,
         executed by order of the Board of Directors, one copy of which
         instrument shall be delivered to the resigning Trustee and one copy to
         the successor trustee. If no successor trustee shall have been so
         appointed and have accepted appointment sixty (60) days after the
         mailing of such notice of resignation to the Noteholders, the resigning
         Trustee may, upon ten (10) business days' notice to the Company and the
         Noteholders, appoint a successor identified in such notice or may
         petition, at the expense of the Company, any court of competent
         jurisdiction for the appointment of a successor trustee, or, any
         Noteholder who has been a bona fide holder of a Note or Notes for at
         least six (6) months may, subject to the provisions of Section 7.9, on
         behalf of himself and all others similarly situated, petition any such
         court for the appointment of a successor trustee. Such court may
         thereupon, after such notice, if any, as it may deem proper and
         prescribe, appoint a successor trustee.

         (b)      In case at any time any of the following shall occur:

                  (1) the Trustee shall fail to comply with Section 8.8 after
written request therefor by the Company or by any Noteholder who has been a bona
fide holder of a Note or Notes for at least six (6) months; or

                                       48
<PAGE>   56
                  (2) the Trustee shall cease to be eligible in accordance with
the provisions of Section 8.9 and shall fail to resign after written request
therefor by the Company or by any such Noteholder; or

                  (3) the Trustee shall become incapable of acting, or shall be
adjudged a bankrupt or insolvent, or a receiver of the Trustee or of its
property shall be appointed, or any public officer shall take charge or control
of the Trustee or of its property or affairs for the purpose of rehabilitation,
conservation or liquidation;

then, in any such case, the Company may remove the Trustee and appoint a
successor trustee by written instrument, in duplicate, executed by order of the
Board of Directors, one copy of which instrument shall be delivered to the
Trustee so removed and one copy to the successor trustee, or, subject to the
provisions of Section 7.9, any Noteholder who has been a bona fide holder of a
Note or Notes for at least six (6) months may, on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a successor trustee; provided,
however, that if no successor Trustee shall have been appointed and have
accepted appointment sixty (60) days after either the Company or the Noteholders
has removed the Trustee, the Trustee so removed may petition any court of
competent jurisdiction for an appointment of a successor trustee. Such court may
thereupon, after such notice, if any, as it may deem proper and prescribe,
remove the Trustee and appoint a successor trustee.

         (c)      The holders of a majority in aggregate principal amount of the
         Notes at the time outstanding may at any time remove the Trustee and
         nominate a successor trustee which shall be deemed appointed as
         successor trustee unless, within ten (10) days after notice to the
         Company of such nomination, the Company objects thereto, in which case
         the Trustee so removed or any Noteholder, or if such Trustee so removed
         or any Noteholder fails to act, the Company, upon the terms and
         conditions and otherwise as in Section 8.10(a) provided, may petition
         any court of competent jurisdiction for an appointment of a successor
         trustee.

         (d)      Any resignation or removal of the Trustee and appointment of a
         successor trustee pursuant to any of the provisions of this Section
         8.10 shall become effective upon acceptance of appointment by the
         successor trustee as provided in Section 8.11.

         Section 8.11. Acceptance By Successor Trustee. Any successor trustee
appointed as provided in Section 8.10 shall execute, acknowledge and deliver to
the Company and to its predecessor trustee an instrument accepting such
appointment hereunder, and thereupon the resignation or removal of the
predecessor trustee shall become effective and such successor trustee, without
any further act, deed or conveyance, shall become vested with all the rights,
powers, duties and obligations of its predecessor hereunder, with like effect as
if originally named as trustee herein; but, nevertheless, on the written request
of the Company or of the successor trustee, the trustee ceasing to act shall,
upon payment of any amount then due it pursuant to the provisions of Section
8.6, execute and deliver an instrument transferring to such successor trustee
all the rights and powers of the trustee so ceasing to act. Upon request of any
such successor trustee, the Company shall execute any and all instruments in
writing for more fully and certainly vesting in and confirming to such successor
trustee all such rights and powers.

                                       49
<PAGE>   57
Any trustee ceasing to act shall, nevertheless, retain a lien upon all property
and funds held or collected by such trustee as such, except for funds held in
trust for the benefit of holders of particular Notes, to secure any amounts then
due it pursuant to the provisions of Section 8.6.

         No successor trustee shall accept appointment as provided in this
Section 8.11 unless, at the time of such acceptance, such successor trustee
shall be qualified under the provisions of Section 8.8 and be eligible under the
provisions of Section 8.9.

         Upon acceptance of appointment by a successor trustee as provided in
this Section 8.11, the Company (or the former trustee, at the written direction
of the Company) shall mail or cause to be mailed notice of the succession of
such trustee hereunder to the holders of Notes at their addresses as they shall
appear on the Note register. If the Company fails to mail such notice within ten
(10) days after acceptance of appointment by the successor trustee, the
successor trustee shall cause such notice to be mailed at the expense of the
Company.

         Section 8.12. Succession By Merger, Etc. Any corporation into which the
Trustee may be merged or converted or with which it may be consolidated, or any
corporation resulting from any merger, conversion or consolidation to which the
Trustee shall be a party, or any corporation succeeding to all or substantially
all of the corporate trust business of the Trustee (including any trust created
by this Indenture), shall be the successor to the Trustee hereunder without the
execution or filing of any paper or any further act on the part of any of the
parties hereto, provided that in the case of any corporation succeeding to all
or substantially all of the corporate trust business of the Trustee, such
corporation shall be qualified under the provisions of Section 8.8 and eligible
under the provisions of Section 8.9.

         In case at the time such successor to the Trustee shall succeed to the
trusts created by this Indenture, any of the Notes shall have been authenticated
but not delivered, any such successor to the Trustee may adopt the certificate
of authentication of any predecessor trustee or authenticating agent appointed
by such predecessor trustee, and deliver such Notes so authenticated; and in
case at that time any of the Notes shall not have been authenticated, any
successor to the Trustee or any authenticating agent appointed by such successor
trustee may authenticate such Notes in the name of the successor trustee; and in
all such cases such certificates shall have the full force that is provided in
the Notes or in this Indenture; provided, however, that the right to adopt the
certificate of authentication of any predecessor Trustee or authenticate Notes
in the name of any predecessor Trustee shall apply only to its successor or
successors by merger, conversion or consolidation.

         Section 8.13. Preferential Collection Of Claims. If and when the
Trustee shall be or become a creditor of the Company (or any other obligor upon
the Notes), the Trustee shall be subject to the provisions of the Trust
Indenture Act regarding the collection of the claims against the Company (or any
such other obligor).

         Section 8.14. Trustee's Application For Instructions From The Company.
Any application by the Trustee for written instructions from the Company (other
than with regard to any action proposed to be taken or omitted to be taken by
the Trustee that affects the rights of the holders of the Notes or holders of
Senior Indebtedness under this Indenture, including, without limitation, under
Article Four hereof) may, at the option of the Trustee, set forth in writing any

                                       50
<PAGE>   58
action proposed to be taken or omitted by the Trustee under this Indenture and
the date on and/or after which such action shall be taken or such omission shall
be effective. The Trustee shall not be liable for any action taken by, or
omission of, the Trustee in accordance with a proposal included in such
application on or after the date specified in such application (which date shall
not be less than three (3) Business Days after the date any officer of the
Company actually receives such application, unless any such officer shall have
consented in writing to any earlier date) unless prior to taking any such action
(or the effective date in the case of an omission), the Trustee shall have
received written instructions in response to such application specifying the
action to be taken or omitted.

                                   ARTICLE 9.

                                 THE NOTEHOLDERS

         Section 9.1. Action By Noteholders. Whenever in this Indenture it is
provided that the holders of a specified percentage in aggregate principal
amount of the Notes may take any action (including the making of any demand or
request, the giving of any notice, consent or waiver or the taking of any other
action), the fact that at the time of taking any such action, the holders of
such specified percentage have joined therein may be evidenced (a) by any
instrument or any number of instruments of similar tenor executed by Noteholders
in person or by agent or proxy appointed in writing, or (b) by the record of the
holders of Notes voting in favor thereof at any meeting of Noteholders duly
called and held in accordance with the provisions of Article Ten, or (c) by a
combination of such instrument or instruments and any such record of such a
meeting of Noteholders. Whenever the Company or the Trustee solicits the taking
of any action by the holders of the Notes, the Company or the Trustee may fix in
advance of such solicitation, a date as the record date for determining holders
entitled to take such action. The record date shall be not more than fifteen
(15) days prior to the date of commencement of solicitation of such action.

         Section 9.2. Proof Of Execution By Noteholders. Subject to the
provisions of Sections 8.1, 8.2 and 10.5, proof of the execution of any
instrument by a Noteholder or its agent or proxy shall be sufficient if made in
accordance with such reasonable rules and regulations as may be prescribed by
the Trustee or in such manner as shall be satisfactory to the Trustee. The
holding of Notes shall be proved by the registry of such Notes or by a
certificate of the Note registrar.

         The record of any Noteholders' meeting shall be proved in the manner
provided in Section 10.6.

         Section 9.3. Who Are Deemed Absolute Owners. The Company, the Trustee,
any paying agent, any conversion agent and any Note registrar may deem the
Person in whose name such Note shall be registered upon the Note register to be,
and may treat it as, the absolute owner of such Note (whether or not such Note
shall be overdue and notwithstanding any notation of ownership or other writing
thereon made by any Person other than the Company or any Note registrar) for the
purpose of receiving payment of or on account of the principal of, premium, if
any, and interest on such Note, for conversion of such Note and for all other
purposes; and neither the Company nor the Trustee nor any paying agent nor any
conversion agent nor any

                                       51
<PAGE>   59
Note registrar shall be affected by any notice to the contrary. All such
payments so made to any holder for the time being, or upon his order, shall be
valid, and, to the extent of the sum or sums so paid, effectual to satisfy and
discharge the liability for monies payable upon any such Note.

         Section 9.4. Company-Owned Notes Disregarded. In determining whether
the holders of the requisite aggregate principal amount of Notes have concurred
in any direction, consent, waiver or other action under this Indenture, Notes
which are owned by the Company or any other obligor on the Notes or any
Affiliate of the Company or any other obligor on the Notes shall be disregarded
and deemed not to be outstanding for the purpose of any such determination;
provided, however, that, for the purposes of determining whether the Trustee
shall be protected in relying on any such direction, consent, waiver or other
action, only Notes which a Responsible Officer knows are so owned shall be so
disregarded. Notes so owned which have been pledged in good faith may be
regarded as outstanding for the purposes of this Section 9.4 if the pledgee
shall establish to the satisfaction of the Trustee the pledgee's right to vote
such Notes and that the pledgee is not the Company, any other obligor on the
Notes or any Affiliate of the Company or any such other obligor. In the case of
a dispute as to such right, any decision by the Trustee taken upon the advice of
counsel shall be full protection to the Trustee. Upon request of the Trustee,
the Company shall furnish to the Trustee promptly an Officers' Certificate
listing and identifying all Notes, if any, known by the Company to be owned or
held by or for the account of any of the above described Persons, and, subject
to Section 8.1, the Trustee shall be entitled to accept such Officers'
Certificate as conclusive evidence of the facts therein set forth and of the
fact that all Notes not listed therein are outstanding for the purpose of any
such determination.

         Section 9.5. Revocation Of Consents; Future Holders Bound. At any time
prior to (but not after) the evidencing to the Trustee, as provided in Section
9.1, of the taking of any action by the holders of the percentage in aggregate
principal amount of the Notes specified in this Indenture in connection with
such action, any holder of a Note which is shown by the evidence to be included
in the Notes the holders of which have consented to such action may, by filing
written notice with the Trustee at its Corporate Trust Office and upon proof of
holding as provided in Section 9.2, revoke such action so far as concerns such
Note. Except as aforesaid, any such action taken by the holder of any Note shall
be conclusive and binding upon such holder and upon all future holders and
owners of such Note and of any Notes issued in exchange or substitution
therefor, irrespective of whether any notation in regard thereto is made upon
such Note or any Note issued in exchange or substitution therefor.

                                  ARTICLE 10.

                             MEETINGS OF NOTEHOLDERS

         Section 10.1. Purpose Of Meetings. A meeting of Noteholders may be
called at any time and from time to time pursuant to the provisions of this
Article Ten for any of the following purposes:

                  (1) to give any notice to the Company or to the Trustee or to
give any directions to the Trustee permitted under this Indenture, or to consent
to the waiving of any default or Event of Default hereunder and its
consequences, or to take any other action authorized to be taken by Noteholders
pursuant to any of the provisions of Article Seven;

                                       52

<PAGE>   60
         (2) to remove the Trustee and nominate a successor trustee pursuant to
the provisions of Article Eight;

         (3) to consent to the execution of an indenture or indentures
supplemental hereto pursuant to the provisions of Section 11.2; or

         (4) to take any other action authorized to be taken by or on behalf of
the holders of any specified aggregate principal amount of the Notes under any
other provision of this Indenture or under applicable law.

         Section 10.2. Call Of Meetings By Trustee. The Trustee may at any time
call a meeting of Noteholders to take any action specified in Section 10.1, to
be held at such time and at such place as the Trustee shall determine. Notice of
every meeting of the Noteholders, setting forth the time and the place of such
meeting and in general terms the action proposed to be taken at such meeting and
the establishment of any record date pursuant to Section 9.1, shall be mailed to
holders of Notes at their addresses as they shall appear on the Note register.
Such notice shall also be mailed to the Company. Such notices shall be mailed
not less than twenty (20) nor more than ninety (90) days prior to the date fixed
for the meeting.

         Any meeting of Noteholders shall be valid without notice if the holders
of all Notes then outstanding are present in person or by proxy or if notice is
waived before or after the meeting by the holders of all Notes outstanding, and
if the Company and the Trustee are either present by duly authorized
representatives or have, before or after the meeting, waived notice.

         Section 10.3. Call Of Meetings By Company Or Noteholders. In case at
any time the Company, pursuant to a resolution of its Board of Directors, or the
holders of at least ten percent (10%) in aggregate principal amount of the Notes
then outstanding, shall have requested the Trustee to call a meeting of
Noteholders, by written request setting forth in reasonable detail the action
proposed to be taken at the meeting, and the Trustee shall not have mailed the
notice of such meeting within twenty (20) days after receipt of such request,
then the Company or such Noteholders may determine the time and the place for
such meeting and may call such meeting to take any action authorized in Section
10.1, by mailing notice thereof as provided in Section 10.2.

         Section 10.4. Qualifications For Voting. To be entitled to vote at any
meeting of Noteholders a person shall (a) be a holder of one or more Notes on
the record date pertaining to such meeting or (b) be a person appointed by an
instrument in writing as proxy by a holder of one or more Notes on the record
date pertaining to such meeting. The only persons who shall be entitled to be
present or to speak at any meeting of Noteholders shall be the persons entitled
to vote at such meeting and their counsel and any representatives of the Trustee
and its counsel and any representatives of the Company and its counsel.

         Section 10.5. Regulations. Notwithstanding any other provisions of this
Indenture, the Trustee may make such reasonable regulations as it may deem
advisable for any meeting of Noteholders, in regard to proof of the holding of
Notes and of the appointment of proxies, and in regard to the appointment and
duties of inspectors of votes, the submission and

                                       53
<PAGE>   61
examination of proxies, certificates and other evidence of the right to vote,
and such other matters concerning the conduct of the meeting as it shall think
fit.

         The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or by Noteholders as provided in Section 10.3, in which case the Company
or the Noteholders calling the meeting, as the case may be, shall in like manner
appoint a temporary chairman. A permanent chairman and a permanent secretary of
the meeting shall be elected by vote of the holders of a majority in principal
amount of the Notes represented at the meeting and entitled to vote at the
meeting.

         Subject to the provisions of Section 9.4, at any meeting each
Noteholder or proxyholder shall be entitled to one vote for each $1,000
principal amount of Notes held or represented by him; provided, however, that no
vote shall be cast or counted at any meeting in respect of any Note challenged
as not outstanding and ruled by the chairman of the meeting to be not
outstanding. The chairman of the meeting shall have no right to vote other than
by virtue of Notes held by him or instruments in writing as aforesaid duly
designating him as the proxy to vote on behalf of other Noteholders. Any meeting
of Noteholders duly called pursuant to the provisions of Section 10.2 or 10.3
may be adjourned from time to time by the holders of a majority of the aggregate
principal amount of Notes represented at the meeting, whether or not
constituting a quorum, and the meeting may be held as so adjourned without
further notice.

         Section 10.6. Voting. The vote upon any resolution submitted to any
meeting of Noteholders shall be by written ballot on which shall be subscribed
the signatures of the holders of Notes or of their representatives by proxy and
the outstanding principal amount of the Notes held or represented by them. The
permanent chairman of the meeting shall appoint two inspectors of votes who
shall count all votes cast at the meeting for or against any resolution and who
shall make and file with the secretary of the meeting their verified written
reports in duplicate of all votes cast at the meeting. A record in duplicate of
the proceedings of each meeting of Noteholders shall be prepared by the
secretary of the meeting and there shall be attached to said record the original
reports of the inspectors of votes on any vote by ballot taken thereat and
affidavits by one or more persons having knowledge of the facts setting forth a
copy of the notice of the meeting and showing that said notice was mailed as
provided in Section 10.2. The record shall show the principal amount of the
Notes voting in favor of or against any resolution. The record shall be signed
and verified by the affidavits of the permanent chairman and secretary of the
meeting and one of the duplicates shall be delivered to the Company and the
other to the Trustee to be preserved by the Trustee, the latter to have attached
thereto the ballots voted at the meeting.

         Any record so signed and verified shall be conclusive evidence of the
matters therein stated.

         Section 10.7. No Delay Of Rights By Meeting. Nothing contained in this
Article Ten shall be deemed or construed to authorize or permit, by reason of
any call of a meeting of Noteholders or any rights expressly or impliedly
conferred hereunder to make such call, any hindrance or delay in the exercise of
any right or rights conferred upon or reserved to the Trustee or to the
Noteholders under any of the provisions of this Indenture or of the Notes.

                                       54
<PAGE>   62
                                  ARTICLE 11.

                             SUPPLEMENTAL INDENTURES

         Section 11.1. Supplemental Indentures Without Consent Of Noteholders.
The Company, when authorized by the resolutions of the Board of Directors, and
the Trustee may, from time to time, and at any time enter into an indenture or
indentures supplemental hereto for one or more of the following purposes:

              (a) make provision with respect to the conversion rights of the
         holders of Notes pursuant to the requirements of Section 15.6 and the
         redemption obligations of the Company pursuant to the requirements of
         Section 3.5(e);

              (b) subject to Article Four, to convey, transfer, assign, mortgage
         or pledge to the Trustee as security for the Notes, any property or
         assets;

              (c) to evidence the succession of another Person to the Company,
         or successive successions, and the assumption by the successor Person
         of the covenants, agreements and obligations of the Company pursuant to
         Article Twelve;

              (d) to add to the covenants of the Company such further covenants,
         restrictions or conditions as the Board of Directors and the Trustee
         shall consider to be for the benefit of the holders of Notes, and to
         make the occurrence, or the occurrence and continuance, of a default in
         any such additional covenants, restrictions or conditions a default or
         an Event of Default permitting the enforcement of all or any of the
         several remedies provided in this Indenture as herein set forth;
         provided, however, that in respect of any such additional covenant,
         restriction or condition, such supplemental indenture may provide for a
         particular period of grace after default (which period may be shorter
         or longer than that allowed in the case of other defaults) or may
         provide for an immediate enforcement upon such default or may limit the
         remedies available to the Trustee upon such default;

              (e) to provide for the issuance under this Indenture of Notes in
         coupon form (including Notes registrable as to principal only) and to
         provide for exchangeability of such Notes with the Notes issued
         hereunder in fully registered form and to make all appropriate changes
         for such purpose;

              (f) to cure any ambiguity or to correct or supplement any
         provision contained herein or in any supplemental indenture that may be
         defective or inconsistent with any other provision contained herein or
         in any supplemental indenture, or to make such other provisions in
         regard to matters or questions arising under this Indenture that shall
         not materially adversely affect the interests of the holders of the
         Notes;

              (g) to evidence and provide for the acceptance of appointment
         hereunder by a successor Trustee with respect to the Notes; or

                                       55
<PAGE>   63
              (h) to modify, eliminate or add to the provisions of this
         Indenture to such extent as shall be necessary to effect the
         qualifications of this Indenture under the Trust Indenture Act, or
         under any similar federal statute hereafter enacted.

         Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by its Secretary or Assistant
Secretary authorizing the execution of any supplemental indenture, the Trustee
is hereby authorized to join with the Company in the execution of any such
supplemental indenture, to make any further appropriate agreements and
stipulations that may be therein contained and to accept the conveyance,
transfer and assignment of any property thereunder, but the Trustee shall not be
obligated to, but may in its discretion, enter into any supplemental indenture
that affects the Trustee's own rights, duties or immunities under this Indenture
or otherwise.

         Any supplemental indenture authorized by the provisions of this Section
11.1 may be executed by the Company and the Trustee without the consent of the
holders of any of the Notes at the time outstanding, notwithstanding any of the
provisions of Section 11.2.

         Notwithstanding any other provision of the Indenture or the Notes, the
Registration Rights Agreement and the obligation to pay Liquidated Damages
thereunder may be amended, modified or waived in accordance with the provisions
of the Registration Rights Agreement.

         Section 11.2. Supplemental Indenture With Consent Of Noteholders. With
the consent (evidenced as provided in Article Nine) of the holders of not less
than a majority in aggregate principal amount of the Notes at the time
outstanding, the Company, when authorized by the resolutions of the Board of
Directors, and the Trustee may, from time to time and at any time, enter into an
indenture or indentures supplemental hereto for the purpose of adding any
provisions to or changing in any manner or eliminating any of the provisions of
this Indenture or any supplemental indenture or of modifying in any manner the
rights of the holders of the Notes; provided, however, that no such supplemental
indenture shall (i) extend the fixed maturity of any Note, or reduce the rate or
extend the time of payment of interest thereon, or reduce the principal amount
thereof or premium, if any, thereon, or reduce any amount payable on redemption
thereof, or impair the right of any Noteholder to institute suit for the payment
thereof, or make the principal thereof or interest or premium, if any, thereon
payable in any coin or currency other than that provided in the Notes, or modify
the provisions of this Indenture with respect to the subordination of the Notes
in a manner adverse to the Noteholders in any material respect, or change the
obligation of the Company to redeem any Note upon the happening of a Fundamental
Change in a manner adverse to the holder of Notes, or impair the right to
convert the Notes into Common Stock subject to the terms set forth herein,
including Section 15.6, in each case, without the consent of the holder of each
Note so affected, or (ii) reduce the aforesaid percentage of Notes, the holders
of which are required to consent to any such supplemental indenture, without the
consent of the holders of all Notes then outstanding.

         Upon the written request of the Company, accompanied by a copy of the
resolutions of the Board of Directors certified by its Secretary or Assistant
Secretary authorizing the execution of any such supplemental indenture, and upon
the filing with the Trustee of evidence of the consent of Noteholders as
aforesaid, the Trustee shall join with the Company in

                                       56
<PAGE>   64
the execution of such supplemental indenture unless such supplemental indenture
affects the Trustee's own rights, duties or immunities under this Indenture or
otherwise, in which case the Trustee may in its discretion, but shall not be
obligated to, enter into such supplemental indenture.

         It shall not be necessary for the consent of the Noteholders under this
Section 11.2 to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.

         Section 11.3. Effect Of Supplemental Indenture. Any supplemental
indenture executed pursuant to the provisions of this Article Eleven shall
comply with the Trust Indenture Act, as then in effect, provided that this
Section 11.3 shall not require such supplemental indenture or the Trustee to be
qualified under the Trust Indenture Act prior to the time such qualification is
in fact required under the terms of the Trust Indenture Act or the Indenture has
been qualified under the Trust Indenture Act, nor shall it constitute any
admission or acknowledgment by any party to such supplemental indenture that any
such qualification is required prior to the time such qualification is in fact
required under the terms of the Trust Indenture Act or the Indenture has been
qualified under the Trust Indenture Act. Upon the execution of any supplemental
indenture pursuant to the provisions of this Article Eleven, this Indenture
shall be and be deemed to be modified and amended in accordance therewith and
the respective rights, limitation of rights, obligations, duties and immunities
under this Indenture of the Trustee, the Company and the holders of Notes shall
thereafter be determined, exercised and enforced hereunder, subject in all
respects to such modifications and amendments and all the terms and conditions
of any such supplemental indenture shall be and be deemed to be part of the
terms and conditions of this Indenture for any and all purposes.

         Section 11.4. Notation On Notes. Notes authenticated and delivered
after the execution of any supplemental indenture pursuant to the provisions of
this Article Eleven may bear a notation in form approved by the Trustee as to
any matter provided for in such supplemental indenture. If the Company or the
Trustee shall so determine, new Notes so modified as to conform, in the opinion
of the Trustee and the Board of Directors, to any modification of this Indenture
contained in any such supplemental indenture may, at the Company's expense, be
prepared and executed by the Company, authenticated by the Trustee (or an
authenticating agent duly appointed by the Trustee pursuant to Section 16.11)
and delivered in exchange for the Notes then outstanding, upon surrender of such
Notes then outstanding.

         Section 11.5. Evidence Of Compliance Of Supplemental Indenture To Be
Furnished To Trustee. Prior to entering into any supplemental indenture, the
Trustee may request an Officers' Certificate and an Opinion of Counsel as
conclusive evidence that any supplemental indenture executed pursuant hereto
complies with the requirements of this Article Eleven.

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<PAGE>   65
                                  ARTICLE 12.

                CONSOLIDATION, MERGER, SALE, CONVEYANCE AND LEASE

         Section 12.1. Company May Consolidate, Etc. On Certain Terms. Subject
to the provisions of Section 12.2, nothing contained in this Indenture or in any
of the Notes shall prevent any consolidation or merger of the Company with or
into any other Person or Persons (whether or not affiliated with the Company),
or successive consolidations or mergers in which the Company or its successor or
successors shall be a party or parties, or shall prevent any sale, conveyance or
lease (or successive sales, conveyances or leases) of all or substantially all
of the property of the Company, to any other Person (whether or not affiliated
with the Company), authorized to acquire and operate the same and that shall be
organized under the laws of the United States of America, any state thereof or
the District of Columbia; provided, however, that upon any such consolidation,
merger, sale, conveyance or lease, the due and punctual payment of the principal
of and premium, if any, and interest (including Liquidated Damages, if any) on
all of the Notes, according to their tenor and the due and punctual performance
and observance of all of the covenants and conditions of this Indenture to be
performed by the Company, shall be expressly assumed, by supplemental indenture
satisfactory in form to the Trustee, executed and delivered to the Trustee by
the Person (if other than the Company) formed by such consolidation, or into
which the Company shall have been merged, or by the Person that shall have
acquired or leased such property, and such supplemental indenture shall provide
for the applicable conversion rights set forth in Section 15.6.

         Section 12.2. Successor Corporation To Be Substituted. In case of any
such consolidation, merger, sale, conveyance or lease and upon the assumption by
the successor Person, by supplemental indenture, executed and delivered to the
Trustee and satisfactory in form to the Trustee, of the due and punctual payment
of the principal of and premium, if any, and interest on all of the Notes and
the due and punctual performance of all of the covenants and conditions of this
Indenture to be performed by the Company, such successor Person shall succeed to
and be substituted for the Company, with the same effect as if it had been named
herein as the party of this first part. Such successor Person thereupon may
cause to be signed, and may issue either in its own name or in the name of
Burr-Brown Corporation any or all of the Notes, issuable hereunder that
theretofore shall not have been signed by the Company and delivered to the
Trustee; and, upon the order of such successor Person instead of the Company and
subject to all the terms, conditions and limitations in this Indenture
prescribed, the Trustee shall authenticate and shall deliver, or cause to be
authenticated and delivered, any Notes that previously shall have been signed
and delivered by the officers of the Company to the Trustee for authentication,
and any Notes that such successor Person thereafter shall cause to be signed and
delivered to the Trustee for that purpose. All the Notes so issued shall in all
respects have the same legal rank and benefit under this Indenture as the Notes
theretofore or thereafter issued in accordance with the terms of this Indenture
as though all of such Notes had been issued at the date of the execution hereof.
In the event of any such consolidation, merger, sale, conveyance or lease, the
Person named as the "Company" in the first paragraph of this Indenture or any
successor that shall thereafter have become such in the manner prescribed in
this Article Twelve may be dissolved, wound up and liquidated at any time
thereafter and such Person shall be released from its liabilities as obligor and
maker of the Notes and from its obligations under this Indenture.

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<PAGE>   66

         In case of any such consolidation, merger, sale, conveyance or lease,
such changes in phraseology and form (but not in substance) may be made in the
Notes thereafter to be issued as may be appropriate.

         Section 12.3. Opinion Of Counsel To Be Given Trustee. The Trustee shall
receive an Officers' Certificate and an Opinion of Counsel as conclusive
evidence that any such consolidation, merger, sale, conveyance or lease and any
such assumption complies with the provisions of this Article Twelve.

                                   ARTICLE 13.

                     SATISFACTION AND DISCHARGE OF INDENTURE

         Section 13.1. Discharge Of Indenture. When (a) the Company shall
deliver to the Trustee for cancellation all Notes theretofore authenticated
(other than any Notes that have been destroyed, lost or stolen and in lieu of or
in substitution for which other Notes shall have been authenticated and
delivered) and not theretofore canceled, or (b) all the Notes not theretofore
canceled or delivered to the Trustee for cancellation shall have become due and
payable, or are by their terms to become due and payable within one year or are
to be called for redemption within one year under arrangements satisfactory to
the Trustee for the giving of notice of redemption, and the Company shall
deposit with the Trustee, in trust, funds sufficient to pay at maturity or upon
redemption of all of the Notes (other than any Notes that shall have been
mutilated, destroyed, lost or stolen and in lieu of or in substitution for which
other Notes shall have been authenticated and delivered) not theretofore
canceled or delivered to the Trustee for cancellation, including principal and
premium, if any, and interest due or to become due to such date of maturity or
redemption date, as the case may be, accompanied by a verification report, as to
the sufficiency of the deposited amount, from an independent certified
accountant or other financial professional satisfactory to the Trustee, and if
the Company shall also pay or cause to be paid all other sums payable hereunder
by the Company, then this Indenture shall cease to be of further effect (except
as to (i) remaining rights of registration of transfer, substitution and
exchange and conversion of Notes, (ii) rights hereunder of Noteholders to
receive payments of principal of and premium, if any, and interest on, the Notes
and the other rights, duties and obligations of Noteholders, as beneficiaries
hereof with respect to the amounts, if any, so deposited with the Trustee and
(iii) the rights, obligations and immunities of the Trustee hereunder), and the
Trustee, on written demand of the Company accompanied by an Officers'
Certificate and an Opinion of Counsel as required by Section 16.5 and at the
cost and expense of the Company, shall execute proper instruments acknowledging
satisfaction of and discharging this Indenture; the Company, however, hereby
agrees to reimburse the Trustee for any costs or expenses thereafter reasonably
and properly incurred by the Trustee and to compensate the Trustee for any
services thereafter reasonably and properly rendered by the Trustee in
connection with this Indenture or the Notes.

         Section 13.2. Deposited Monies To Be Held In Trust By Trustee. Subject
to Section 13.4, all monies deposited with the Trustee pursuant to Section 13.1,
provided such deposit was not in violation of Article Four, shall be held in
trust for the sole benefit of the Noteholders and not to be subject to the
subordination provisions of Article Four, and such monies shall be applied by
the Trustee to the payment, either directly or through any paying

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<PAGE>   67
agent (including the Company if acting as its own paying agent), to the holders
of the particular Notes for the payment or redemption of which such monies have
been deposited with the Trustee, of all sums due and to become due thereon for
principal and interest and premium, if any.

         Section 13.3. Paying Agent To Repay Monies Held. Upon the satisfaction
and discharge of this Indenture, all monies then held by any paying agent of the
Notes (other than the Trustee) shall, upon written request of the Company, be
repaid to it or paid to the Trustee, and thereupon such paying agent shall be
released from all further liability with respect to such monies.

         Section 13.4. Return Of Unclaimed Monies. Subject to the requirements
of applicable law, any monies deposited with or paid to the Trustee for payment
of the principal of, premium, if any, or interest on Notes and not applied but
remaining unclaimed by the holders of Notes for two years after the date upon
which the principal of, premium, if any, or interest on such Notes, as the case
may be, shall have become due and payable, shall be repaid to the Company by the
Trustee on demand and all liability of the Trustee shall thereupon cease with
respect to such monies; and the holder of any of the Notes shall thereafter look
only to the Company for any payment that such holder may be entitled to collect
unless an applicable abandoned property law designates another Person.

         Section 13.5. Reinstatement. If the Trustee or the paying agent is
unable to apply any money in accordance with Section 13.2 by reason of any order
or judgment of any court or governmental authority enjoining, restraining or
otherwise prohibiting such application, the Company's obligations under this
Indenture and the Notes shall be revived and reinstated as though no deposit had
occurred pursuant to Section 13.1 until such time as the Trustee or the paying
agent is permitted to apply all such money in accordance with Section 13.2;
provided, however, that if the Company makes any payment of interest on or
principal of any Note following the reinstatement of its obligations, the
Company shall be subrogated to the rights of the holders of such Notes to
receive such payment from the money held by the Trustee or paying agent.

                                  ARTICLE 14.

                           IMMUNITY OF INCORPORATORS,
                      STOCKHOLDERS, OFFICERS AND DIRECTORS

         Section 14.1. Indenture And Notes Solely Corporate Obligations. No
recourse for the payment of the principal of or premium, if any, or interest on
any Note, or for any claim based thereon or otherwise in respect thereof, and no
recourse under or upon any obligation, covenant or agreement of the Company in
this Indenture or in any supplemental indenture or in any Note, or because of
the creation of any indebtedness represented thereby, shall be had against any
incorporator, stockholder, employee, agent, officer, director or subsidiary, as
such, past, present or future, of the Company or of any successor corporation,
either directly or through the Company or any successor corporation, whether by
virtue of any constitution, statute or rule of law, or by the enforcement of any
assessment or penalty or otherwise; it being expressly

                                       60
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understood that all such liability is hereby expressly waived and released as a
condition of, and as a consideration for, the execution of this Indenture and
the issue of the Notes.

                                   ARTICLE 15.

                               CONVERSION OF NOTES

         Section 15.1. Right To Convert. Subject to and upon compliance with the
provisions of this Indenture, including, without limitation, Article Four, the
holder of any Note shall have the right, at its option, at any time after the
original issuance of the Notes hereunder through the close of business on the
final maturity date of the Notes (except that, with respect to any Note or
portion of a Note that shall be called for redemption, such right shall
terminate, except as provided in Section 15.2, Section 3.2 or Section 3.4, at
the close of business on the Business Day next preceding the date fixed for
redemption of such Note or portion of a Note unless the Company shall default in
payment due upon redemption thereof) to convert the principal amount of any such
Note, or any portion of such principal amount which is $1,000 or an integral
multiple thereof, into that number of fully paid and non-assessable shares of
Common Stock (as such shares shall then be constituted) obtained by dividing the
principal amount of the Note or portion thereof surrendered for conversion by
the Conversion Price in effect at such time, by surrender of the Note so to be
converted in whole or in part in the manner provided, together with any required
funds, in Section 15.2. A Note in respect of which a holder is exercising its
option to require redemption upon a Fundamental Change pursuant to Section 3.5
may be converted only if such holder withdraws its election to exercise in
accordance with Section 3.5. A holder of Notes is not entitled to any rights of
a holder of Common Stock until such holder has converted his Notes to Common
Stock, and only to the extent such Notes are deemed to have been converted to
Common Stock under this Article Fifteen.

         Section 15.2. Exercise Of Conversion Privilege; Issuance Of Common
Stock On Conversion; No Adjustment For Interest Or Dividends. In order to
exercise the conversion privilege with respect to any Note in certificated form,
the holder of any such Note to be converted in whole or in part shall surrender
such Note, duly endorsed, at an office or agency maintained by the Company
pursuant to Section 5.2, accompanied by the funds, if any, required by the
penultimate paragraph of this Section 15.2, and shall give written notice of
conversion in the form provided on the Notes (or such other notice which is
acceptable to the Company) to the office or agency that the holder elects to
convert such Note or the portion thereof specified in said notice. Such notice
shall also state the name or names (with address or addresses) in which the
certificate or certificates for shares of Common Stock which shall be issuable
on such conversion shall be issued, and shall be accompanied by transfer taxes,
if required pursuant to Section 15.7. Each such Note surrendered for conversion
shall, unless the shares issuable on conversion are to be issued in the same
name as the registration of such Note, be duly endorsed by, or be accompanied by
instruments of transfer in form satisfactory to the Company duly executed by,
the holder or his duly authorized attorney.

         In order to exercise the conversion privilege with respect to any
interest in a Global Note, the beneficial holder must complete, or cause to be
completed, the appropriate instruction form for conversion pursuant to the
Depository's book-entry conversion program, deliver, or cause to be delivered,
by book-entry delivery an interest in such Global Note, furnish

                                       61
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appropriate endorsements and transfer documents if required by the Company or
the Trustee or conversion agent, and pay the funds, if any, required by this
Section 15.2 and any transfer taxes if required pursuant to Section 15.7.

         As promptly as practicable after satisfaction of the requirements for
conversion set forth above, subject to compliance with any restrictions on
transfer if shares issuable on conversion are to be issued in a name other than
that of the Noteholder (as if such transfer were a transfer of the Note or Notes
(or portion thereof) so converted), the Company shall issue and shall deliver to
such Noteholder at the office or agency maintained by the Company for such
purpose pursuant to Section 5.2, a certificate or certificates for the number of
full shares of Common Stock issuable upon the conversion of such Note or portion
thereof as determined by the Company in accordance with the provisions of this
Article Fifteen and a check or cash in respect of any fractional interest in
respect of a share of Common Stock arising upon such conversion, calculated by
the Company as provided in Section 15.3. In case any Note of a denomination
greater than $1,000 shall be surrendered for partial conversion, and subject to
Section 2.3, the Company shall execute and the Trustee shall authenticate and
deliver to the holder of the Note so surrendered, without charge to him, a new
Note or Notes in authorized denominations in an aggregate principal amount equal
to the unconverted portion of the surrendered Note.

         Each conversion shall be deemed to have been effected as to any such
Note (or portion thereof) on the date on which the requirements set forth above
in this Section 15.2 have been satisfied as to such Note (or portion thereof),
and the Person in whose name any certificate or certificates for shares of
Common Stock shall be issuable upon such conversion shall be deemed to have
become on said date the holder of record of the shares represented thereby;
provided, however, that any such surrender on any date when the stock transfer
books of the Company shall be closed shall constitute the Person in whose name
the certificates are to be issued as the record holder thereof for all purposes
on the next succeeding day on which such stock transfer books are open, but such
conversion shall be at the Conversion Price in effect on the date upon which
such Note shall be surrendered.

         No adjustment in respect of interest on any Note converted or dividends
on any shares issued upon conversion of such Note will be made upon any
conversion except as set forth in the next sentence. If this Note (or portion
hereof) is surrendered for conversion during the period from the close of
business on any record date for the payment of interest to the close of business
on the Business Day preceding the following interest payment date and either (x)
has not been called for redemption on a redemption date that occurs during such
period or (y) is not to be redeemed in connection with a Fundamental Change on a
Repurchase Date that occurs during such period, this Note (or portion hereof
being converted) must be accompanied by an amount, in New York Clearing House
funds or other funds acceptable to the Company, equal to the interest payable on
such interest payment date on the principal amount being converted; provided,
however, that no such payment shall be required if there shall exist at the time
of conversion a default in the payment of interest on the Notes.

         Upon the conversion of an interest in a Global Note, the Trustee (or
other conversion agent appointed by the Company), or the Custodian at the
direction of the Trustee (or other conversion agent appointed by the Company),
shall make a notation on such Global Note

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as to the reduction in the principal amount represented thereby. The Company
shall notify the Trustee in writing of any conversions of Notes effected through
any conversion agent other than the Trustee.

         Section 15.3. Cash Payments In Lieu Of Fractional Shares. No fractional
shares of Common Stock or scrip representing fractional shares shall be issued
upon conversion of Notes. If more than one Note shall be surrendered for
conversion at one time by the same holder, the number of full shares that shall
be issuable upon conversion shall be computed on the basis of the aggregate
principal amount of the Notes (or specified portions thereof to the extent
permitted hereby) so surrendered. If any fractional share of stock would be
issuable upon the conversion of any Note or Notes, the Company shall make an
adjustment and payment therefor in cash at the current market price thereof to
the holder of Notes. The current market price of a share of Common Stock shall
be the Closing Price on the last Business Day immediately preceding the day on
which the Notes (or specified portions thereof) are deemed to have been
converted.

         Section 15.4. Conversion Price. The conversion price shall be as
specified in the form of Note (herein called the "Conversion Price") attached as
Exhibit A hereto, subject to adjustment as provided in this Article Fifteen.

         Section 15.5. Adjustment Of Conversion Price. The Conversion Price
shall be adjusted from time to time by the Company as follows:

         (a) In case the Company shall hereafter pay a dividend or make a
distribution to all holders of the outstanding Common Stock in shares of Common
Stock, the Conversion Price shall be reduced so that the same shall equal the
price determined by multiplying the Conversion Price in effect at the opening of
business on the date following the date fixed for the determination of
stockholders entitled to receive such dividend or other distribution by a
fraction, the numerator of which shall be the number of shares of the Common
Stock outstanding at the close of business on the date fixed for such
determination, and the denominator of which shall be the sum of such number of
shares and the total number of shares constituting such dividend or other
distribution, such reduction to become effective immediately after the opening
of business on the day following the date fixed for such determination. For the
purpose of this paragraph (a), the number of shares of Common Stock at any time
outstanding shall not include shares held in the treasury of the Company. The
Company will not pay any dividend or make any distribution on shares of Common
Stock held in the treasury of the Company. If any dividend or distribution of
the type described in this Section 15.5(a) is declared but not so paid or made,
the Conversion Price shall again be adjusted to the Conversion Price that would
then be in effect if such dividend or distribution had not been declared.

         (b) In case the Company shall issue rights or warrants to all holders
of its outstanding shares of Common Stock entitling them (for a period expiring
within forty-five (45) days after the date fixed for determination of
stockholders entitled to receive such rights or warrants) to subscribe for or
purchase shares of Common Stock at a price per share less than the Current
Market Price (as defined below) on the date fixed for determination of
stockholders entitled to receive such rights or warrants, the Conversion

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<PAGE>   71
Price shall be adjusted so that the same shall equal the price determined by
multiplying the Conversion Price in effect immediately prior to the date fixed
for determination of stockholders entitled to receive such rights or warrants by
a fraction, the numerator of which shall be the number of shares of Common Stock
outstanding at the close of business on the date fixed for determination of
stockholders entitled to receive such rights or warrants plus the number of
shares that the aggregate offering price of the total number of shares so
offered would purchase at such Current Market Price, and the denominator of
which shall be the number of shares of Common Stock outstanding on the date
fixed for determination of stockholders entitled to receive such rights or
warrants plus the total number of additional shares of Common Stock offered for
subscription or purchase. Such adjustment shall be successively made whenever
any such rights or warrants are issued, and shall become effective immediately
after the opening of business on the day following the date fixed for
determination of stockholders entitled to receive such rights or warrants. To
the extent that shares of Common Stock are not delivered after the expiration of
such rights or warrants, the Conversion Price shall be readjusted to the
Conversion Price that would then be in effect had the adjustments made upon the
issuance of such rights or warrants been made on the basis of delivery of only
the number of shares of Common Stock actually delivered. In the event that such
rights or warrants are not so issued, the Conversion Price shall again be
adjusted to be the Conversion Price that would then be in effect if such date
fixed for the determination of stockholders entitled to receive such rights or
warrants had not been fixed. In determining whether any rights or warrants
entitle the holders to subscribe for or purchase shares of Common Stock at less
than such Current Market Price, and in determining the aggregate offering price
of such shares of Common Stock, there shall be taken into account any
consideration received by the Company for such rights or warrants and any amount
payable on exercise or conversion thereof, the value of such consideration, if
other than cash, to be determined by the Board of Directors.

         (c) In case outstanding shares of Common Stock shall be subdivided into
a greater number of shares of Common Stock, the Conversion Price in effect at
the opening of business on the day following the day upon which such subdivision
becomes effective shall be proportionately reduced, and conversely, in case
outstanding shares of Common Stock shall be combined into a smaller number of
shares of Common Stock, the Conversion Price in effect at the opening of
business on the day following the day upon which such combination becomes
effective shall be proportionately increased, such reduction or increase, as the
case may be, to become effective immediately after the opening of business on
the day following the day upon which such subdivision or combination becomes
effective.

         (d) In case the Company shall, by dividend or otherwise, distribute to
all holders of its Common Stock shares of any class of capital stock of the
Company (other than any dividends or distributions to which Section 15.5(a)
applies) or evidences of its indebtedness or assets (including securities, but
excluding any rights or warrants referred to in Section 15.5(b), and excluding
any dividend or distribution (x) paid exclusively in cash or (y) referred to in
Section 15.5(a) (any of the foregoing hereinafter in this Section 15.5(d) called
the "Securities")), then, in each such case (unless the Company elects to
reserve such Securities for distribution to the Noteholders upon the conversion

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<PAGE>   72
         of the Notes so that any such holder converting Notes will receive upon
         such conversion, in addition to the shares of Common Stock to which
         such holder is entitled, the amount and kind of such Securities which
         such holder would have received if such holder had converted its Notes
         into Common Stock immediately prior to the Record Date (as defined in
         Section 15.5(h)(4) for such distribution of the Securities)), the
         Conversion Price shall be reduced so that the same shall be equal to
         the price determined by multiplying the Conversion Price in effect on
         the Record Date with respect to such distribution by a fraction, the
         numerator of which shall be the Current Market Price per share of the
         Common Stock on such Record Date less the fair market value (as
         determined by the Board of Directors, whose determination shall be
         conclusive, and described in a resolution of the Board of Directors) on
         the Record Date of the portion of the Securities so distributed
         applicable to one share of Common Stock and the denominator of which
         shall be the Current Market Price per share of the Common Stock, such
         reduction to become effective immediately prior to the opening of
         business on the day following such Record Date; provided, however, that
         in the event the then fair market value (as so determined) of the
         portion of the Securities so distributed applicable to one share of
         Common Stock is equal to or greater than the Current Market Price of
         the Common Stock on the Record Date, in lieu of the foregoing
         adjustment, adequate provision shall be made so that each Noteholder
         shall have the right to receive upon conversion the amount of
         Securities such holder would have received had such holder converted
         each Note on the Record Date. In the event that such dividend or
         distribution is not so paid or made, the Conversion Price shall again
         be adjusted to be the Conversion Price that would then be in effect if
         such dividend or distribution had not been declared. If the Board of
         Directors determines the fair market value of any distribution for
         purposes of this Section 15.5(d) by reference to the actual or when
         issued trading market for any securities, it must in doing so consider
         the prices in such market over the same period used in computing the
         Current Market Price of the Common Stock.

         Under the provisions of the Company's Preferred Shares Rights Plan (the
"Rights Plan"), upon conversion of the Notes into Common Stock, to the extent
that the Rights Plan is still in effect upon such conversion, the holders of
Notes will receive, in addition to the Common Stock, the rights described
therein (whether or not the rights have separated from the Common Stock at the
time of conversion), subject to the limitations set forth in the Rights Plan.

         Rights or warrants distributed by the Company to all holders of Common
Stock entitling the holders thereof to subscribe for or purchase shares of the
Company's capital stock (either initially or under certain circumstances), which
rights or warrants, until the occurrence of a specified event or events
("Trigger Event"): (i) are deemed to be transferred with such shares of Common
Stock; (ii) are not exercisable; and (iii) are also issued in respect of future
issuances of Common Stock, shall be deemed not to have been distributed for
purposes of this Section 15.5 (and no adjustment to the Conversion Price under
this Section 15.5 will be required) until the occurrence of the earliest Trigger
Event, whereupon such rights and warrants shall be deemed to have been
distributed and an appropriate adjustment (if any is required) to the Conversion
Price shall be made under this Section 15.5(d). If any such right or warrant,
including any such existing rights or warrants distributed prior to the date of
this Indenture, are subject to events, upon the occurrence of which such rights
or warrants become exercisable to purchase different securities, evidences of
indebtedness or other assets, then the date of the occurrence of any and

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<PAGE>   73
each such event shall be deemed to be the date of distribution and record date
with respect to new rights or warrants with such rights (and a termination or
expiration of the existing rights or warrants without exercise by any of the
holders thereof). In addition, in the event of any distribution (or deemed
distribution) of rights or warrants, or any Trigger Event or other event (of the
type described in the preceding sentence) with respect thereto that was counted
for purposes of calculating a distribution amount for which an adjustment to the
Conversion Price under this Section 15.5 was made, (1) in the case of any such
rights or warrants that shall all have been redeemed or repurchased without
exercise by any holders thereof, the Conversion Price shall be readjusted upon
such final redemption or repurchase to give effect to such distribution or
Trigger Event, as the case may be, as though it were a cash distribution, equal
to the per share redemption or repurchase price received by a holder or holders
of Common Stock with respect to such rights or warrants (assuming such holder
had retained such rights or warrants), made to all holders of Common Stock as of
the date of such redemption or repurchase, and (2) in the case of such rights or
warrants that shall have expired or been terminated without exercise by any
holders thereof, the Conversion Price shall be readjusted as if such rights and
warrants had not been issued.

         No adjustment of the Conversion Price shall be made pursuant to this
Section 15.5(d) in respect of rights or warrants distributed or deemed
distributed on any Trigger Event to the extent that such rights or warrants are
actually distributed, or reserved by the Company for distribution to holders of
Notes upon conversion by such holders of Notes to Common Stock.

         For purposes of this Section 15.5(d) and Sections 15.5(a) and (b), any
dividend or distribution to which this Section 15.5(d) is applicable that also
includes shares of Common Stock, or rights or warrants to subscribe for or
purchase shares of Common Stock (or both), shall be deemed instead to be (1) a
dividend or distribution of the evidences of indebtedness, assets or shares of
capital stock other than such shares of Common Stock or rights or warrants (and
any Conversion Price reduction required by this Section 15.5(d) with respect to
such dividend or distribution shall then be made) immediately followed by (2) a
dividend or distribution of such shares of Common Stock or such rights or
warrants (and any further Conversion Price reduction required by Sections
15.5(a) and (b) with respect to such dividend or distribution shall then be
made), except (A) the Record Date of such dividend or distribution shall be
substituted as "the date fixed for the determination of stockholders entitled to
receive such dividend or other distribution", "the date fixed for the
determination of stockholders entitled to receive such rights or warrants" and
"the date fixed for such determination" within the meaning of Sections 15.5(a)
and (b), and (B) any shares of Common Stock included in such dividend or
distribution shall not be deemed "outstanding at the close of business on the
date fixed for such determination" within the meaning of Section 15.5(a).

               (e) In case the Company shall, by dividend or otherwise,
         distribute to all holders of its Common Stock cash (excluding (x) any
         quarterly cash dividend on the Common Stock to the extent the aggregate
         cash dividend per share of Common Stock in any fiscal quarter does not
         exceed the greater of (A) the amount per share of Common Stock of the
         next preceding quarterly cash dividend on the Common Stock to the
         extent that such preceding quarterly dividend did not require any
         adjustment of the Conversion Price pursuant to this Section 15.5(e) (as
         adjusted to reflect subdivisions, or combinations

                                       66
<PAGE>   74
of the Common Stock), and (B) 3.75% of the arithmetic average of the Closing
Price (determined as set forth in Section 15.5(h)) during the ten Trading Days
(as defined in Section 15.5(h)) immediately prior to the date of declaration of
such dividend, and (y) any dividend or distribution in connection with the
liquidation, dissolution or winding up of the Company, whether voluntary or
involuntary), then, in such case, the Conversion Price shall be reduced so that
the same shall equal the price determined by multiplying the Conversion Price in
effect immediately prior to the close of business on such record date by a
fraction, the numerator of which shall be the Current Market Price of the Common
Stock on the record date less the amount of cash so distributed (and not
excluded as provided above) applicable to one share of Common Stock, and the
denominator of which shall be such Current Market Price of the Common Stock,
such reduction to be effective immediately prior to the opening of business on
the day following the record date; provided, however, that in the event the
portion of the cash so distributed applicable to one share of Common Stock is
equal to or greater than the Current Market Price of the Common Stock on the
record date, in lieu of the foregoing adjustment, adequate provision shall be
made so that each Noteholder shall have the right to receive upon conversion the
amount of cash such holder would have received had such holder converted each
Note on the record date. In the event that such dividend or distribution is not
so paid or made, the Conversion Price shall again be adjusted to be the
Conversion Price that would then be in effect if such dividend or distribution
had not been declared. If any adjustment is required to be made as set forth in
this Section 15.5(e) as a result of a distribution that is a quarterly dividend,
such adjustment shall be based upon the amount by which such distribution
exceeds the amount of the quarterly cash dividend permitted to be excluded
pursuant hereto. If an adjustment is required to be made as set forth in this
Section 15.5(e) above as a result of a distribution that is not a quarterly
dividend, such adjustment shall be based upon the full amount of the
distribution.

         (f) In case a tender or exchange offer made by the Company or any
Subsidiary for all or any portion of the Common Stock shall expire and such
tender or exchange offer (as amended upon the expiration thereof) shall require
the payment to stockholders of consideration per share of Common Stock having a
fair market value (as determined by the Board of Directors, whose determination
shall be conclusive and described in a resolution of the Board of Directors)
that as of the last time (the "Expiration Time") tenders or exchanges may be
made pursuant to such tender or exchange offer (as it may be amended) exceeds
the Current Market Price of the Common Stock on the Trading Day next succeeding
the Expiration Time, the Conversion Price shall be reduced so that the same
shall equal the price determined by multiplying the Conversion Price in effect
immediately prior to the Expiration Time by a fraction the numerator of which
shall be the number of shares of Common Stock outstanding (including any
tendered or exchanged shares) at the Expiration Time multiplied by the Current
Market Price of the Common Stock on the Trading Day next succeeding the
Expiration Time and the denominator of which shall be the sum of (x) the fair
market value (determined as aforesaid) of the aggregate consideration payable to
stockholders based on the acceptance (up to any maximum specified in the terms
of the tender or exchange offer) of all shares validly tendered or exchanged and
not withdrawn as of the Expiration Time (the shares deemed so accepted, up to
any such maximum, being

                                       67
<PAGE>   75
referred to as the "Purchased Shares") and (y) the product of the number of
shares of Common Stock outstanding (less any Purchased Shares) at the Expiration
Time and the Current Market Price of the Common Stock on the Trading Day next
succeeding the Expiration Time, such reduction to become effective immediately
prior to the opening of business on the Trading Day following the Expiration
Time. In the event that the Company is obligated to purchase shares pursuant to
any such tender or exchange offer, but the Company is permanently prevented by
applicable law from effecting any such purchases or all such purchases are
rescinded, the Conversion Price shall again be adjusted to be the Conversion
Price that would then be in effect if such tender or exchange offer had not been
made.

         (g) In case of a tender or exchange offer made by a Person other than
the Company or any Subsidiary for an amount that increases the offeror's
ownership of Common Stock to more than twenty-five percent (25%) of the Common
Stock outstanding and shall involve the payment by such Person of consideration
per share of Common Stock having a fair market value (as determined by the Board
of Directors, whose determination shall be conclusive, and described in a
resolution of the Board of Directors) that as of the last time (the "Offer
Expiration Time") tenders or exchanges may be made pursuant to such tender or
exchange offer (as it shall have been amended) exceeds the Current Market Price
of the Common Stock on the Trading Day next succeeding the Offer Expiration
Time, and in which, as of the Offer Expiration Time the Board of Directors is
not recommending rejection of the offer, the Conversion Price shall be reduced
so that the same shall equal the price determined by multiplying the Conversion
Price in effect immediately prior to the Offer Expiration Time by a fraction the
numerator of which shall be the number of shares of Common Stock outstanding
(including any tendered or exchanged shares) at the Offer Expiration Time
multiplied by the Current Market Price of the Common Stock on the Trading Day
next succeeding the Offer Expiration Time and the denominator of which shall be
the sum of (x) the fair market value (determined as aforesaid) of the aggregate
consideration payable to stockholders based on the acceptance (up to any maximum
specified in the terms of the tender or exchange offer) of all shares validly
tendered or exchanged and not withdrawn as of the Offer Expiration Time (the
shares deemed so accepted, up to any such maximum, being referred to as the
"Accepted Purchased Shares") and (y) the product of the number of shares of
Common Stock outstanding (less any Accepted Purchased Shares) at the Offer
Expiration Time and the Current Market Price of the Common Stock on the Trading
Day next succeeding the Offer Expiration Time, such reduction to become
effective immediately prior to the opening of business on the Trading Day
following the Offer Expiration Time. In the event that such Person is obligated
to purchase shares pursuant to any such tender or exchange offer, but such
Person is permanently prevented by applicable law from effecting any such
purchases or all such purchases are rescinded, the Conversion Price shall again
be adjusted to be the Conversion Price that would then be in effect if such
tender or exchange offer had not been made. Notwithstanding the foregoing, the
adjustment described in this Section 15.5(g) shall not be made if, as of the
Offer Expiration Time, the offering documents with respect to such offer
disclose a plan or intention to cause the Company to engage in any transaction
described in Article Twelve.

                                       68
<PAGE>   76
         (h) For purposes of this Section 15.5, the following terms shall have
the meaning indicated:

         (1) "Closing Price" with respect to any security on any day shall mean
the closing sale price, regular way, on such day or, in case no such sale takes
place on such day, the average of the reported closing bid and asked prices,
regular way, in each case as quoted on the Nasdaq National Market or, if such
security is not quoted or listed or admitted to trading on such Nasdaq National
Market, on the principal national securities exchange or quotation system on
which such security is quoted or listed or admitted to trading or, if not quoted
or listed or admitted to trading on any national securities exchange or
quotation system, the average of the closing bid and asked prices of such
security on the over-the-counter market on the day in question as reported by
the National Quotation Bureau Incorporated, or a similar generally accepted
reporting service, or if not so available, in such manner as furnished by any
New York Stock Exchange member firm selected from time to time by the Board of
Directors for that purpose, or a price determined in good faith by the Board of
Directors or, to the extent permitted by applicable law, a duly authorized
committee thereof, whose determination shall be conclusive.

         (2) "Current Market Price" shall mean the average of the daily Closing
Prices per share of Common Stock for the ten consecutive Trading Days
immediately prior to the date in question except as hereinafter provided for
purposes of any computation under Section 15.5(f) or (g); provided, however,
that (1) if the "ex" date (as hereinafter defined) for any event (other than the
issuance or distribution requiring such computation and other than the tender or
exchange offer requiring such computation under Section 15.5(f) or (g)) that
requires an adjustment to the Conversion Price pursuant to Section 15.5(a), (b),
(c), (d), (e), (f) or (g) occurs during such ten consecutive Trading Days, the
Closing Price for each Trading Day prior to the "ex" date for such other event
shall be adjusted by multiplying such Closing Price by the same fraction by
which the Conversion Price is so required to be adjusted as a result of such
other event, (2) if the "ex" date for any event (other than the issuance or
distribution requiring such computation and other than the tender or exchange
offer requiring such computation under Section 15.5(f) or (g)) that requires an
adjustment to the Conversion Price pursuant to Section 15.5(a), (b), (c), (d),
(e), (f) or (g) occurs on or after the "ex" date for the issuance or
distribution requiring such computation and prior to the day in question, the
Closing Price for each Trading Day on and after the "ex" date for such other
event shall be adjusted by multiplying such Closing Price by the reciprocal of
the fraction by which the Conversion Price is so required to be adjusted as a
result of such other event, and (3) if the "ex" date for the issuance or
distribution requiring such computation is prior to the day in question, after
taking into account any adjustment required pursuant to clause (1) or (2) of
this proviso, the Closing Price for each Trading Day on or after such "ex" date
shall be adjusted by adding thereto the amount of any cash and the fair market
value (as determined by the Board of Directors or, to the extent permitted by
applicable law, a duly authorized committee thereof in a manner consistent with
any determination of such value for purposes of Section 15.5(d), (f) or (g),
whose determination shall be conclusive and described in a resolution of the
Board of Directors or such duly authorized committee thereof, as the case may
be) of the evidences of indebtedness, shares of capital stock or assets being
distributed applicable to one share of Common Stock as of the close of business
on the day before such "ex" date. For purposes of any computation under Section
15.5(f) or (g), the "Current Market Price" of the Common Stock on any date shall
be

                                       69
<PAGE>   77
deemed to be the average of the daily Closing Prices per share of Common
Stock for such day and the next two succeeding Trading Days; provided, however,
that if the "ex" date for any event (other than the tender or exchange offer
requiring such computation under Section 15.5(f) or (g)) that requires an
adjustment to the Conversion Price pursuant to Section 15.5(a), (b), (c), (d),
(e), (f) or (g) occurs on or after the Expiration Time or Offer Expiration Time,
as the case may be, for the tender or exchange offer requiring such computation
and prior to the day in question, the Closing Price for each Trading Day on and
after the "ex" date for such other event shall be adjusted as provided in
clauses (1), (2) and (3) of the proviso contained in the first sentence of this
Section 15.5(h)(2). For purpose of this paragraph, the term "ex" date, (1) when
used with respect to any issuance or distribution, means the first date on which
the Common Stock trades, regular way, on the relevant exchange or in the
relevant market from which the Closing Price was obtained without the right to
receive such issuance or distribution, (2) when used with respect to any
subdivision or combination of shares of Common Stock, means the first date on
which the Common Stock trades, regular way, on such exchange or in such market
after the time at which such subdivision or combination becomes effective, and
(3) when used with respect to any tender or exchange offer means the first date
on which the Common Stock trades, regular way, on such exchange or in such
market after the Expiration Time or the Offer Expiration Time of such offer.

         (3) "Fair Market Value" shall mean the amount which a willing buyer
would pay a willing seller in an arm's-length transaction.

         (4) "Record Date" shall mean, with respect to any dividend,
distribution or other transaction or event in which the holders of Common Stock
have the right to receive any cash, securities or other property or in which the
Common Stock (or other applicable security) is exchanged for or converted into
any combination of cash, securities or other property, the date fixed for
determination of stockholders entitled to receive such cash, securities or other
property (whether such date is fixed by the Board of Directors or by statute,
contract or otherwise).

         (5) "Trading Day" shall mean (x) if the applicable security is quoted
on the Nasdaq National Market, a day on which trades may be made thereon or (y)
if the applicable security is listed or admitted for trading on the New York
Stock Exchange or another national securities exchange, a day on which the New
York Stock Exchange or another national securities exchange is open for business
or (z) if the applicable security is not so listed, admitted for trading or
quoted, any day other than a Saturday or Sunday or a day on which banking
institutions in the State of New York are authorized or obligated by law or
executive order to close.

                  (i) The Company may make such reductions in the Conversion
         Price, in addition to those required by Sections 15.5(a), (b), (c),
         (d), (e), (f) or (g) as the Board of Directors considers to be
         advisable to avoid or diminish any income tax to holders of Common
         Stock or rights to purchase Common Stock resulting from any dividend or
         distribution of stock (or rights to acquire stock) or from any event
         treated as such for income tax purposes.

                                       70
<PAGE>   78
         To the extent permitted by applicable law, the Company from time to
time may reduce the Conversion Price by any amount for any period of time if the
period is at least twenty (20) days, the reduction is irrevocable during the
period and the Board of Directors shall have made a determination that such
reduction would be in the best interests of the Company, which determination
shall be conclusive. Whenever the Conversion Price is reduced pursuant to the
preceding sentence, the Company shall mail to holders of record of the Notes a
notice of the reduction at least fifteen (15) days prior to the date the reduced
Conversion Price takes effect, and such notice shall state the reduced
Conversion Price and the period during which it will be in effect.

               (j) No adjustment in the Conversion Price shall be required
         unless such adjustment would require an increase or decrease of at
         least one percent (1%) in such price; provided, however, that any
         adjustments that by reason of this Section 15.5(j) are not required to
         be made shall be carried forward and taken into account in any
         subsequent adjustment. All calculations under this Article Fifteen
         shall be made by the Company and shall be made to the nearest cent or
         to the nearest one-hundredth (1/100) of a share, as the case may be. No
         adjustment need be made for rights to purchase Common Stock pursuant to
         a Company plan for reinvestment of dividends or interest. To the extent
         the Notes become convertible into cash, assets, property or securities
         (other than capital stock of the Company), no adjustment need be made
         thereafter as to the cash, assets, property or such securities.
         Interest will not accrue on the cash.

               (k) Whenever the Conversion Price is adjusted as herein provided,
         the Company shall promptly file with the Trustee and any conversion
         agent other than the Trustee an Officers' Certificate setting forth the
         Conversion Price after such adjustment and setting forth a brief
         statement of the facts requiring such adjustment. Unless and until a
         Responsible Officer of the Trustee shall have received such Officers'
         Certificate, the Trustee shall not be deemed to have knowledge of any
         adjustment of the Conversion Price and may assume that the last
         Conversion Price of which it has knowledge is still in effect. Promptly
         after delivery of such certificate, the Company shall prepare a notice
         of such adjustment of the Conversion Price setting forth the adjusted
         Conversion Price and the date on which each adjustment becomes
         effective and shall mail such notice of such adjustment of the
         Conversion Price to the holder of each Note at his last address
         appearing on the Note register provided for in Section 2.5 of this
         Indenture, within twenty (20) days after execution thereof. Failure to
         deliver such notice shall not affect the legality or validity of any
         such adjustment.

               (l) In any case in which this Section 15.5 provides that an
         adjustment shall become effective immediately after (1) a record date
         or Record Date for an event, (2) the date fixed for the determination
         of stockholders entitled to receive a dividend or distribution pursuant
         to Section 15.5(a), (3) a date fixed for the determination of
         stockholders entitled to receive rights or warrants pursuant to Section
         15.5(b), (4) the Expiration Time for any tender or exchange offer
         pursuant to Section 15.5(f), or (5) the Offer Expiration Time for a
         tender or exchange offer pursuant to Section 15.5(g) (each a
         "Determination Date"), the Company may elect to defer until the
         occurrence of the relevant Adjustment Event (as hereinafter defined)
         (x) issuing to the holder of any Note converted after such
         Determination Date and before the occurrence of such Adjustment

                                       71
<PAGE>   79
      Event, the additional shares of Common Stock or other securities issuable
      upon such conversion by reason of the adjustment required by such
      Adjustment Event over and above the Common Stock issuable upon such
      conversion before giving effect to such adjustment and (y) paying to such
      holder any amount in cash in lieu of any fraction pursuant to Section
      15.3. For purposes of this Section 15.5(l), the term "Adjustment Event"
      shall mean:

                  (a) in any case referred to in clause (1) hereof, the
         occurrence of such event,

                  (b) in any case referred to in clause (2) hereof, the date any
         such dividend or distribution is paid or made,

                  (c) in any case referred to in clause (3) hereof, the date of
         expiration of such rights or warrants, and

                  (d) in any case referred to in clause (4) or clause (5)
         hereof, the date a sale or exchange of Common Stock pursuant to such
         tender or exchange offer is consummated and becomes irrevocable.

         (m) For purposes of this Section 15.5, the number of shares of Common
      Stock at any time outstanding shall not include shares held in the
      treasury of the Company but shall include shares issuable in respect of
      scrip certificates issued in lieu of fractions of shares of Common Stock.
      The Company will not pay any dividend or make any distribution on shares
      of Common Stock held in the treasury of the Company.

         Section 15.6. Effect Of Reclassification, Consolidation, Merger Or
Sale. If any of the following events occur, namely (i) any reclassification or
change of the outstanding shares of Common Stock (other than a subdivision or
combination to which Section 15.5(c) applies), (ii) any consolidation, merger or
combination of the Company with another Person as a result of which holders of
Common Stock shall be entitled to receive stock, other securities or other
property or assets (including cash) with respect to or in exchange for such
Common Stock, or (iii) any sale or conveyance of all or substantially all of the
properties and assets of the Company to any other Person as a result of which
holders of Common Stock shall be entitled to receive stock, other securities or
other property or assets (including cash) with respect to or in exchange for
such Common Stock, then the Company or the successor or purchasing Person, as
the case may be, shall execute with the Trustee a supplemental indenture (which
shall comply with the Trust Indenture Act as in force at the date of execution
of such supplemental indenture) providing that such Note shall be convertible
into the kind and amount of shares of stock, other securities or other property
or assets (including cash) receivable upon such reclassification, change,
consolidation, merger,

                                       72
<PAGE>   80
combination, sale or conveyance by a holder of a number of shares of Common
Stock issuable upon conversion of such Notes (assuming, for such purposes, a
sufficient number of authorized shares of Common Stock are available to convert
all such Notes) immediately prior to such reclassification, change,
consolidation, merger, combination, sale or conveyance assuming such holder of
Common Stock did not exercise his rights of election, if any, as to the kind or
amount of stock, other securities or other property or assets (including cash)
receivable upon such reclassification, change, consolidation, merger,
combination, sale or conveyance (provided that, if the kind or amount of stock,
other securities or other property or assets (including cash) receivable upon
such reclassification, change, consolidation, merger, combination, sale or
conveyance is not the same for each share of Common Stock in respect of which
such rights of election shall not have been exercised ("non-electing share"),
then for the purposes of this Section 15.6 the kind and amount of stock, other
securities or other property or assets (including cash) receivable upon such
reclassification, change, consolidation, merger, combination, sale or conveyance
for each non-electing share shall be deemed to be the kind and amount so
receivable per share by a plurality of the non-electing shares). Such
supplemental indenture shall provide for adjustments which shall be as nearly
equivalent as may be practicable to the adjustments provided for in this Article
Fifteen.

         The Company shall cause notice of the execution of such supplemental
indenture to be mailed to each holder of Notes, at its address appearing on the
Note register provided for in Section 2.5 of this Indenture, within twenty (20)
days after execution thereof. Failure to deliver such notice shall not affect
the legality or validity of such supplemental indenture.

         The above provisions of this Section shall similarly apply to
successive reclassifications, changes, consolidations, mergers, combinations,
sales and conveyances.

         If this Section 15.6 applies to any event or occurrence, Section 15.5
shall not apply.

         Section 15.7. Taxes On Shares Issued. The issue of stock certificates
on conversions of Notes shall be made without charge to the converting
Noteholder for any tax in respect of the issue thereof. The Company shall not,
however, be required to pay any tax which may be payable in respect of any
transfer involved in the issue and delivery of stock in any name other than that
of the holder of any Note converted, and the Company shall not be required to
issue or deliver any such stock certificate unless and until the Person or
Persons requesting the issue thereof shall have paid to the Company the amount
of such tax or shall have established to the satisfaction of the Company that
such tax has been paid.

         Section 15.8. Reservation Of Shares; Shares To Be Fully Paid;
Compliance With Governmental Requirements; Listing Of Common Stock. The Company
shall provide, free from preemptive rights, out of its authorized but unissued
shares or shares held in treasury, sufficient shares of Common Stock to provide
for the conversion of the Notes from time to time as such Notes are presented
for conversion.

         Before taking any action which would cause an adjustment reducing the
Conversion Price below the then par value, if any, of the shares of Common Stock
issuable upon conversion of the Notes, the Company will take all corporate
action which may, in the opinion of its counsel, be necessary in order that the
Company may validly and legally issue shares of such Common Stock at such
adjusted Conversion Price.

         The Company covenants that all shares of Common Stock which may be
issued upon conversion of Notes will upon issue be fully paid and non-assessable
by the Company and free from all taxes, liens and charges with respect to the
issue thereof.

                                       73
<PAGE>   81
         The Company covenants that, if any shares of Common Stock to be
provided for the purpose of conversion of Notes hereunder require registration
with or approval of any governmental authority under any federal or state law
before such shares may be validly issued upon conversion, the Company will in
good faith and as expeditiously as possible, to the extent then permitted by the
rules and interpretations of the Securities and Exchange Commission (or any
successor thereto), endeavor to secure such registration or approval, as the
case may be.

         The Company further covenants that, if at any time the Common Stock
shall be listed on the Nasdaq National Market or any other national securities
exchange or automated quotation system, the Company will, if permitted by the
rules of such exchange or automated quotation system, list and keep listed, so
long as the Common Stock shall be so listed on such exchange or automated
quotation system, all Common Stock issuable upon conversion of the Note;
provided, however, that, if the rules of such exchange or automated quotation
system permit the Company to defer the listing of such Common Stock until the
first conversion of the Notes into Common Stock in accordance with the
provisions of this Indenture, the Company covenants to list such Common Stock
issuable upon conversion of the Notes in accordance with the requirements of
such exchange or automated quotation system at such time.

         Section 15.9. Responsibility Of Trustee. The Trustee and any other
conversion agent shall not at any time be under any duty or responsibility to
any holder of Notes to determine the Conversion Price or whether any facts exist
which may require any adjustment of the Conversion Price, or with respect to the
nature or extent or calculation of any such adjustment when made, or with
respect to the method employed, or herein or in any supplemental indenture
provided to be employed, in making the same. The Trustee and any other
conversion agent shall not be accountable with respect to the validity or value
(or the kind or amount) of any shares of Common Stock, or of any securities or
property, which may at any time be issued or delivered upon the conversion of
any Note; and the Trustee and any other conversion agent make no representations
with respect thereto. Neither the Trustee nor any conversion agent shall be
responsible for any failure of the Company to issue, transfer or deliver any
shares of Common Stock or stock certificates or other securities or property or
cash upon the surrender of any Note for the purpose of conversion or to comply
with any of the duties, responsibilities or covenants of the Company contained
in this Article Fifteen. Without limiting the generality of the foregoing,
neither the Trustee nor any conversion agent shall be under any responsibility
to determine the correctness of any provisions contained in any supplemental
indenture entered into pursuant to Section 15.6 relating either to the kind or
amount of shares of stock or securities or property (including cash) receivable
by Noteholders upon the conversion of their Notes after any event referred to in
such Section 15.6 or to any adjustment to be made with respect thereto, but,
subject to the provisions of Section 8.1, may accept as conclusive evidence of
the correctness of any such provisions, and shall be protected in relying upon,
the Officers' Certificate (which the Company shall be obligated to file with the
Trustee prior to the execution of any such supplemental indenture) with respect
thereto.

         Section 15.10. Notice To Holders Prior To Certain Actions. In case:

          (a) the Company shall declare a dividend (or any other distribution)
    on its Common Stock that would require an adjustment in the Conversion Price
    pursuant to Section 15.5; or

                                       74
<PAGE>   82
          (b) the Company shall authorize the granting to the holders of all or
    substantially all of its Common Stock of rights or warrants to subscribe for
    or purchase any share of any class or any other rights or warrants; or

          (c) of any reclassification or reorganization of the Common Stock of
    the Company (other than a subdivision or combination of its outstanding
    Common Stock, or a change in par value, or from par value to no par value,
    or from no par value to par value), or of any consolidation or merger to
    which the Company is a party and for which approval of any stockholders of
    the Company is required, or of the sale or transfer of all or substantially
    all of the assets of the Company or any Significant Subsidiary; or

          (d) of the voluntary or involuntary dissolution, liquidation or
    winding up of the Company or any Significant Subsidiary;

the Company shall cause to be filed with the Trustee and to be mailed to each
holder of Notes at his address appearing on the Note register provided for in
Section 2.5 of this Indenture, as promptly as possible but in any event at least
ten (10) days prior to the applicable date hereinafter specified, a notice
stating (x) the date on which a record is to be taken for the purpose of such
dividend, distribution or rights or warrants, or, if a record is not to be
taken, the date as of which the holders of Common Stock of record to be entitled
to such dividend, distribution or rights are to be determined, or (y) the date
on which such reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up is expected to become effective or occur,
and the date as of which it is expected that holders of Common Stock of record
shall be entitled to exchange their Common Stock for securities or other
property deliverable upon such reclassification, consolidation, merger, sale,
transfer, dissolution, liquidation or winding up. Failure to give such notice,
or any defect therein, shall not affect the legality or validity of such
dividend, distribution, reclassification, consolidation, merger, sale, transfer,
dissolution, liquidation or winding up.

                                  ARTICLE 16.

                            MISCELLANEOUS PROVISIONS

         Section 16.1. Provisions Binding On Company's Successors. All the
covenants, stipulations, promises and agreements by the Company contained in
this Indenture shall bind its successors and assigns whether so expressed or
not.

         Section 16.2. Official Acts By Successor Corporation. Any act or
proceeding by any provision of this Indenture authorized or required to be done
or performed by any board, committee or officer of the Company shall and may be
done and performed with like force and effect by the like board, committee or
officer of any Person that shall at the time be the lawful sole successor of the
Company.

         Section 16.3. Addresses For Notices, Etc. Any notice or demand which by
any provision of this Indenture is required or permitted to be given or served
by the Trustee or by the holders of Notes on the Company shall be deemed to have
been sufficiently given or made, for all purposes, if given or served by being
deposited postage prepaid by registered or certified mail

                                       75
<PAGE>   83
in a post office letter box addressed (until another address is filed by the
Company with the Trustee) to Burr-Brown Corporation, 6730 South Tucson
Boulevard, Tucson, Arizona 85706, Attention: Treasurer. Any notice, direction,
request or demand hereunder to or upon the Trustee shall be deemed to have been
sufficiently given or made, for all purposes, if given or served by being
deposited, postage prepaid, by registered or certified mail in a post office
letter box addressed to the Corporate Trust Office, which office is, at the date
as of which this Indenture is dated, located at 114 W. 47th Street, New York,
New York 10036-1532, Attention: Corporate Trust Department (Burr-Brown
Corporation, 4 1/4% Convertible Subordinated Notes due 2007 ).

         The Trustee, by notice to the Company, may designate additional or
different addresses for subsequent notices or communications.

         Any notice or communication mailed to a Noteholder shall be mailed to
him by first class mail, postage prepaid, at his address as it appears on the
Note register and shall be sufficiently given to him if so mailed within the
time prescribed.

         Failure to mail a notice or communication to a Noteholder or any defect
in it shall not affect its sufficiency with respect to other Noteholders. If a
notice or communication is mailed in the manner provided above, it is duly
given, whether or not the addressee receives it.

         Section 16.4. Governing Law. This Indenture and each Note shall be
deemed to be a contract made under the laws of the State of New York, and for
all purposes shall be construed in accordance with the laws of the State of New
York, without regard to the conflict of laws provisions thereof.

         Section 16.5. Evidence Of Compliance With Conditions Precedent;
Certificates To Trustee. Upon any application or demand by the Company to the
Trustee to take any action under any of the provisions of this Indenture, the
Company shall furnish to the Trustee an Officers' Certificate stating that all
conditions precedent, if any, provided for in this Indenture relating to the
proposed action have been complied with, and an Opinion of Counsel stating that,
in the opinion of such counsel, all such conditions precedent have been complied
with.

         Each certificate or opinion provided for in this Indenture and
delivered to the Trustee with respect to compliance with a condition or covenant
provided for in this Indenture shall include: (1) a statement that the person
making such certificate or opinion has read such covenant or condition; (2) a
brief statement as to the nature and scope of the examination or investigation
upon which the statement or opinion contained in such certificate or opinion is
based; (3) a statement that, in the opinion of such person, he has made such
examination or investigation as is necessary to enable him to express an
informed opinion as to whether or not such covenant or condition has been
complied with; and (4) a statement as to whether or not, in the opinion of such
person, such condition or covenant has been complied with.

         Section 16.6. Legal Holidays. In any case in which the date of maturity
of interest on or principal of the Notes or the date fixed for redemption of any
Note will not be a Business Day, then payment of such interest on or principal
of the Notes need not be made on such date, but may be made on the next
succeeding Business Day with the same force and effect

                                       76
<PAGE>   84
as if made on the date of maturity or the date fixed for redemption, and no
interest shall accrue for the period from and after such date.

         Section 16.7. Trust Indenture Act. This Indenture is hereby made
subject to, and shall be governed by, the provisions of the Trust Indenture Act
required to be part of and to govern indentures qualified under the Trust
Indenture Act; provided, however, that, unless otherwise required by law,
notwithstanding the foregoing, this Indenture and the Notes issued hereunder
shall not be subject to the provisions of subsections (a)(1), (a)(2), and (a)(3)
of Section 314 of the Trust Indenture Act as now in effect or as hereafter
amended or modified; provided further that this Section 16.7 shall not require
this Indenture or the Trustee to be qualified under the Trust Indenture Act
prior to the time such qualification is in fact required under the terms of the
Trust Indenture Act, nor shall it constitute any admission or acknowledgment by
any party to the Indenture that any such qualification is required prior to the
time such qualification is in fact required under the terms of the Trust
Indenture Act. If any provision hereof limits, qualifies or conflicts with
another provision hereof which is required to be included in an indenture
qualified under the Trust Indenture Act, such required provision shall control.

         Section 16.8. No Security Interest Created. Nothing in this Indenture
or in the Notes, expressed or implied, shall be construed to constitute a
security interest under the Uniform Commercial Code or similar legislation, as
now or hereafter enacted and in effect, in any jurisdiction in which property of
the Company or its subsidiaries is located.

         Section 16.9. Benefits Of Indenture. Nothing in this Indenture or in
the Notes, express or implied, shall give to any Person, other than the parties
hereto, any paying agent, any authenticating agent, any Note registrar and their
successors hereunder, the holders of Notes and the holders of Senior
Indebtedness, any benefit or any legal or equitable right, remedy or claim under
this Indenture.

         Section 16.10. Table Of Contents, Headings, Etc. The table of contents
and the titles and headings of the articles and Sections of this Indenture have
been inserted for convenience of reference only, are not to be considered a part
hereof, and shall in no way modify or restrict any of the terms or provisions
hereof.

         Section 16.11. Authenticating Agent. The Trustee may appoint an
authenticating agent that shall be authorized to act on its behalf, and subject
to its direction, in the authentication and delivery of Notes in connection with
the original issuance thereof and transfers and exchanges of Notes hereunder,
including under Sections 2.4, 2.5, 2.6, 2.7, 3.3 and 3.5, as fully to all
intents and purposes as though the authenticating agent had been expressly
authorized by this Indenture and those Sections to authenticate and deliver
Notes. For all purposes of this Indenture, the authentication and delivery of
Notes by the authenticating agent shall be deemed to be authentication and
delivery of such Notes "by the Trustee" and a certificate of authentication
executed on behalf of the Trustee by an authenticating agent shall be deemed to
satisfy any requirement hereunder or in the Notes for the Trustee's certificate
of authentication. Such authenticating agent shall at all times be a Person
eligible to serve as trustee hereunder pursuant to Section 8.9.

                                       77
<PAGE>   85
         Any corporation into which any authenticating agent may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, consolidation or conversion to which any authenticating agent
shall be a party, or any corporation succeeding to the corporate trust business
of any authenticating agent, shall be the successor of the authenticating agent
hereunder, if such successor corporation is otherwise eligible under this
Section 16.11, without the execution or filing of any paper or any further act
on the part of the parties hereto or the authenticating agent or such successor
corporation.

         Any authenticating agent may at any time resign by giving written
notice of resignation to the Trustee and to the Company. The Trustee may at any
time terminate the agency of any authenticating agent by giving written notice
of termination to such authenticating agent and to the Company. Upon receiving
such a notice of resignation or upon such a termination, or in case at any time
any authenticating agent shall cease to be eligible under this Section , the
Trustee shall either promptly appoint a successor authenticating agent or itself
assume the duties and obligations of the former authenticating agent under this
Indenture and, upon such appointment of a successor authenticating agent, if
made, shall give written notice of such appointment of a successor
authenticating agent to the Company and shall mail notice of such appointment of
a successor authenticating agent to all holders of Notes as the names and
addresses of such holders appear on the Note register.

         The Company agrees to pay to the authenticating agent from time to time
such reasonable compensation for its services as shall be agreed upon in writing
between the Company and the authenticating agent.

         The provisions of Sections 8.2, 8.3, 8.4, 9.3 and this Section 16.11
shall be applicable to any authenticating agent.

         Section 16.12. Execution In Counterparts. This Indenture may be
executed in any number of counterparts, each of which shall be an original, but
such counterparts shall together constitute but one and the same instrument.

         Section 16.13. Severability. In case any provision in this Indenture or
in the Notes shall be invalid, illegal or unenforceable, then (to the extent
permitted by law) the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

         United States Trust Company of New York, hereby accepts the trusts in
this Indenture declared and provided, upon the terms and conditions herein above
set forth.



                            (Signature Page Follows)

                                       78
<PAGE>   86



         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be
duly executed.

                                              BURR-BROWN CORPORATION

                                              By: /s/ J. Scott Blouin
                                                       ------------------------
                                              Name: J. Scott Blouin
                                              Title: Chief Financial Officer

                                              UNITED STATES TRUST COMPANY
                                              OF NEW YORK, as Trustee

                                              By: /s/ James Logan
                                                 ------------------------------
                                              Name: James Logan
                                              Title: Vice President
<PAGE>   87
                                    EXHIBIT A

                  For Global Note only: UNLESS THIS CERTIFICATE IS PRESENTED BY
AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET,
NEW YORK, NEW YORK) (THE "DEPOSITARY", WHICH TERM INCLUDES ANY SUCCESSOR
DEPOSITARY FOR THE CERTIFICATES) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF
TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE
NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITARY (AND ANY PAYMENT HEREIN IS MADE TO CEDE & CO.
OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE
DEPOSITARY), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY
OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE &
CO., HAS AN INTEREST HEREIN.

                  THE NOTE EVIDENCED HEREBY HAS NOT BEEN REGISTERED UNDER THE
UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY
STATE SECURITIES LAWS, AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD WITHIN THE
UNITED STATES OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS EXCEPT AS
SET FORTH IN THE FOLLOWING SENTENCE. BY ITS ACQUISITION HEREOF, THE HOLDER (1)
REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE
144A UNDER THE SECURITIES ACT) OR (B) IT IS AN INSTITUTIONAL "ACCREDITED
INVESTOR" (AS DEFINED IN RULE 501(A)(1), (2), (3) OR (7) UNDER THE SECURITIES
ACT) ("INSTITUTIONAL ACCREDITED INVESTOR"); (2) AGREES THAT IT WILL NOT, PRIOR
TO EXPIRATION OF THE HOLDING PERIOD APPLICABLE TO SALES OF THE NOTE EVIDENCED
HEREBY UNDER RULE 144(K) UNDER THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION),
RESELL OR OTHERWISE TRANSFER THE NOTE EVIDENCED HEREBY OR THE COMMON STOCK
ISSUABLE UPON CONVERSION OF SUCH NOTE EXCEPT (A) TO BURR-BROWN CORPORATION OR
ANY SUBSIDIARY THEREOF, (B) INSIDE THE UNITED STATES TO A QUALIFIED
INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES ACT, (C)
INSIDE THE UNITED STATES TO AN INSTITUTIONAL ACCREDITED INVESTOR THAT, PRIOR TO
SUCH TRANSFER, FURNISHES TO UNITED STATES TRUST COMPANY OF NEW YORK, AS TRUSTEE
(OR A SUCCESSOR TRUSTEE, AS APPLICABLE), A SIGNED LETTER CONTAINING CERTAIN
REPRESENTATIONS AND AGREEMENTS RELATING TO THE RESTRICTIONS ON TRANSFER OF THE
NOTE EVIDENCED HEREBY (THE FORM OF WHICH LETTER CAN BE OBTAINED FROM SUCH
TRUSTEE OR A SUCCESSOR TRUSTEE, AS APPLICABLE), (D) OUTSIDE THE UNITED STATES IN
COMPLIANCE WITH RULE 904 UNDER THE SECURITIES ACT, (E) PURSUANT TO THE EXEMPTION
FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE)
OR (F) PURSUANT TO A REGISTRATION STATEMENT WHICH HAS BEEN DECLARED EFFECTIVE
UNDER THE SECURITIES ACT (AND WHICH CONTINUES TO BE EFFECTIVE AT THE TIME OF
SUCH TRANSFER); (3) PRIOR TO SUCH TRANSFER (OTHER THAN A TRANSFER PURSUANT TO
CLAUSE (2)(F) ABOVE), IT WILL FURNISH TO UNITED STATES


                                      A-1
<PAGE>   88

TRUST COMPANY OF NEW YORK, AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE,
SUCH CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS THE TRUSTEE MAY
REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN
EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT; AND (4) AGREES THAT IT WILL DELIVER TO EACH
PERSON TO WHOM THE NOTE EVIDENCED HEREBY IS TRANSFERRED (EXCEPT TRANFERS
PURSUANT TO CLAUSES 2(E) OR 2(F) ABOVE, OR PURSUANT TO RULE 144(K)) A NOTICE
SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IN CONNECTION WITH ANY TRANSFER OF
THE NOTE EVIDENCED HEREBY PRIOR TO THE EXPIRATION OF THE HOLDING PERIOD
APPLICABLE TO SALES OF THE NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER THE
SECURITIES ACT (OR ANY SUCCESSOR PROVISION), THE HOLDER MUST CHECK THE
APPROPRIATE BOX SET FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER OF SUCH
TRANSFER AND SUBMIT THIS CERTIFICATE TO UNITED STATES TRUST COMPANY OF NEW YORK,
AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE). IF THE PROPOSED TRANSFEREE
IS AN INSTITUTIONAL ACCREDITED INVESTOR OR IS A PURCHASER WHO IS NOT A U.S.
PERSON, THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH TO UNITED STATES TRUST
COMPANY OF NEW YORK, AS TRUSTEE (OR A SUCCESSOR TRUSTEE, AS APPLICABLE), SUCH
CERTIFICATIONS, LEGAL OPINIONS OR OTHER INFORMATION AS SUCH TRUSTEE MAY
REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN
EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT. THIS LEGEND WILL BE REMOVED UPON THE EARLIER
OF THE TRANSFER OF THE NOTE EVIDENCED HEREBY PURSUANT TO CLAUSES 2(E) OR (2)(F)
ABOVE, OR UPON ANY TRANSFER OF THE NOTE EVIDENCED HEREBY UNDER RULE 144(K) UNDER
THE SECURITIES ACT (OR ANY SUCCESSOR PROVISION). AS USED HEREIN, THE TERMS
"UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO THEM BY REGULATION
S UNDER THE SECURITIES ACT.
                                      A-2


<PAGE>   89
                             BURR-BROWN CORPORATION

                 4 1/4% CONVERTIBLE SUBORDINATED NOTES DUE 2007

                                                              CUSIP: 122 574 AD8

No. 1                                                         $250,000,000

         Burr-Brown Corporation, a corporation duly organized and validly
existing under the laws of the State of Delaware (herein called the "Company",
which term includes any successor corporation under the Indenture referred to on
the reverse hereof), for value received hereby promises to pay to Cede & Co.,
registered assigns, the principal sum of Two hundred and fifty million dollars
($250,000,000) on February 15, 2007, at the office or agency of the Company
maintained for that purpose in accordance with the terms of the Indenture, in
such coin or currency of the United States of America as at the time of payment
shall be legal tender for the payment of public and private debts, and to pay
interest, semi-annually on February 15 and August 15 of each year, commencing
August 15, 2000, on said principal sum at said office or agency, in like coin or
currency, at the rate per annum of 4 1/4%, from February 15 or August 15, as the
case may be, next preceding the date of this Note to which interest has been
paid or duly provided for, unless the date hereof is a date to which interest
has been paid or duly provided for, in which case from the date of this Note, or
unless no interest has been paid or duly provided for on the Notes, in which
case from February 24, 2000, until payment of said principal sum has been made
or duly provided for. Notwithstanding the foregoing, if the date hereof is after
any February 1 or August 1, as the case may be, and before the following
February 15 or August 15, this Note shall bear interest from such February 15 or
August 15; provided, however, that if the Company shall default in the payment
of interest due on such February 15 or August 15, then this Note shall bear
interest from the next preceding February 15 or August 15 to which interest has
been paid or duly provided for or, if no interest has been paid or duly provided
for on such Note, from February 24, 2000. Except as otherwise provided in the
Indenture, the interest payable on the Note pursuant to the Indenture on any
February 15 or August 15 will be paid to the Person entitled thereto as it
appears in the Note register at the close of business on the record date, which
shall be the February 1 or August 1 (whether or not a Business Day) next
preceding such February 15 or August 15, as provided in the Indenture; provided,
however, that any such interest not punctually paid or duly provided for shall
be payable as provided in the Indenture. Interest may, at the option of the
Company, be paid either (i) by check mailed to the registered address of such
Person (provided that the holder of Notes with an aggregate principal amount in
excess of $2,000,000 shall, at the written election of such holder, be paid by
wire transfer of immediately available funds) or (ii) by transfer to an account
maintained by such Person located in the United States; provided, however, that
payments to the Depositary will be made by wire transfer of immediately
available funds to the account of the Depositary or its nominee.

         Reference is made to the further provisions of this Note set forth on
the reverse hereof, including, without limitation, provisions subordinating the
payment of principal of and premium, if any, and interest on the Notes to the
prior payment in full of all Senior Indebtedness, as defined in the Indenture,
and provisions giving the holder of this Note the right to convert this Note
into Common Stock of the Company on the terms and subject to the limitations
referred to
                                      A-3
<PAGE>   90
on the reverse hereof and as more fully specified in the Indenture.
Such further provisions shall for all purposes have the same effect as though
fully set forth at this place.

         This Note shall be deemed to be a contract made under the laws of the
State of New York, and for all purposes shall be construed in accordance with
and governed by the laws of the State of New York, without regard to principles
of conflicts of laws.

         This Note shall not be valid or become obligatory for any purpose until
the certificate of authentication hereon shall have been manually signed by the
Trustee or a duly authorized authenticating agent under the Indenture.

         IN WITNESS WHEREOF, the Company has caused this Note to be duly
executed.

                                BURR-BROWN CORPORATION

                                By:
                                  -----------------------------
                                Name:
                                  -----------------------------
                                Title:
Attest:                           -----------------------------
     -----------------------------
Name:
     -----------------------------
Title:
     -----------------------------
Dated:
     -----------------------------

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is one of the Notes described in the within-named Indenture.
UNITED STATES TRUST COMPANY OF NEW YORK, as Trustee

[By:
   -----------------------------
         Authorized Signatory
                                 ,or

By:
   -----------------------------]
     As Authenticating Agent
    (if different from Trustee)

                                      A-4
<PAGE>   91



                             FORM OF REVERSE OF NOTE

                             BURR-BROWN CORPORATION

                 4 1/4% CONVERTIBLE SUBORDINATED NOTES DUE 2007

                  This Note is one of a duly authorized issue of Notes of the
Company, designated as its 4 1/4% Convertible Subordinated Notes due 2007
(herein called the "Notes"), limited to the aggregate principal amount of
$287,500,000 all issued or to be issued under and pursuant to an Indenture dated
as of February 24, 2000 (herein called the "Indenture"), between the Company and
United States Trust Company of New York, as trustee (herein called the
"Trustee"), to which Indenture and all indentures supplemental thereto reference
is hereby made for a description of the rights, limitations of rights,
obligations, duties and immunities thereunder of the Trustee, the Company and
the holders of the Notes.

                  In case an Event of Default (as defined in the Indenture)
shall have occurred and be continuing, the principal of, premium, if any, and
accrued interest (including Liquidated Damages (as defined in the Registration
Rights Agreement), if any) on all Notes may be declared by either the Trustee or
the holders of not less than 25% in aggregate principal amount of the Notes then
outstanding, and upon said declaration shall become, due and payable, in the
manner, with the effect and subject to the conditions provided in the Indenture.

                  The Indenture contains provisions permitting the Company and
the Trustee, with the consent of the holders of not less than a majority in
aggregate principal amount of the Notes at the time outstanding, to execute
supplemental indentures adding any provisions to or changing in any manner or
eliminating any of the provisions of the Indenture or of any supplemental
indenture or modifying in any manner the rights of the holders of the Notes;
provided, however, that no such supplemental indenture shall (i) extend the
fixed maturity of any Note, or reduce the rate or extend the time of payment of
interest thereon, or reduce the principal amount thereof or premium, if any,
thereon, or reduce any amount payable upon redemption thereof, or impair the
right of any Noteholder to institute suit for the payment thereof, or make the
principal thereof or interest or premium, if any, thereon payable in any coin or
currency other than that provided in the Notes, or modify the provisions of the
Indenture with respect to the subordination of the Notes in a manner adverse to
the Noteholders in any material respect, or change the obligation of the Company
to redeem any Note upon the happening of a Fundamental Change (as defined in the
Indenture) in a manner adverse to the holder of the Notes, or impair the right
to convert the Notes into Common Stock subject to the terms set forth in the
Indenture, including Section 15.6 thereof, without the consent of the holder of
each Note so affected or (ii) reduce the aforesaid percentage of Notes, the
holders of which are required to consent to any such supplemental indenture,
without the consent of the holders of all Notes then outstanding. Subject to the
provisions of the Indenture, the holders of a majority in aggregate principal
amount of the Notes at the time outstanding may on behalf of the holders of all
of the Notes waive any past default or Event of Default under the Indenture and
its consequences except a default in the payment of interest (including
Liquidated Damages, if any) or any premium on, or the principal of, any of the
Notes, or a failure by the Company to convert any Notes into Common Stock of the
Company, or a default in the payment of the redemption price pursuant to Article
Three of the Indenture, or a default in respect of a covenant or provisions of
the Indenture which under
                                      A-5

<PAGE>   92
Article Eleven of the Indenture cannot be modified without the consent of the
holders of each or all Notes then outstanding or affected thereby. Any such
consent or waiver by the holder of this Note (unless revoked as provided in the
Indenture) shall be conclusive and binding upon such holder and upon all future
holders and owners of this Note and any Notes which may be issued in exchange or
substitution hereof, irrespective of whether or not any notation thereof is made
upon this Note or such other Notes.

                  The indebtedness evidenced by the Notes is, to the extent and
in the manner provided in the Indenture, expressly subordinated and subject in
right of payment to the prior payment in full of all Senior Indebtedness of the
Company, whether outstanding at the date of the Indenture or thereafter
incurred, and this Note is issued subject to the provisions of the Indenture
with respect to such subordination. Each holder of this Note, by accepting the
same, agrees to and shall be bound by such provisions and authorizes the Trustee
on its behalf to take such action as may be necessary or appropriate to
effectuate the subordination so provided and appoints the Trustee his
attorney-in-fact for such purpose.

                  No reference herein to the Indenture and no provision of this
Note or of the Indenture shall alter or impair the obligation of the Company,
which is absolute and unconditional, to pay the principal of and any premium and
interest (including Liquidated Damages, if any) on this Note at the place, at
the respective times, at the rate and in the coin or currency herein prescribed.

                  Interest on the Notes shall be computed on the basis of a
360-day year of twelve 30-day months.

                  The Notes are issuable in fully registered form, without
coupons, in denominations of $1,000 principal amount and any integral multiple
of $1,000. At the office or agency of the Company referred to on the face
hereof, and in the manner and subject to the limitations provided in the
Indenture, without payment of any service charge but with payment of a sum
sufficient to cover any tax, assessment or other governmental charge that may be
imposed in connection with any registration or exchange of Notes, Notes may be
exchanged for a like aggregate principal amount of Notes of any other authorized
denominations.

                  The Notes will not be redeemable at the option of the Company
prior to February 20, 2003. At any time on or after February 20, 2003, and prior
to maturity, the Notes may be redeemed at the option of the Company, in whole or
in part, upon notice as set forth in Section 3.2, at the following redemption
prices (expressed as percentages of the principal amount), together in each case
with accrued and unpaid interest, if any (including Liquidated Damages, if any)
to, but excluding, the date fixed for redemption:
<TABLE>
<CAPTION>

         Period                                                             Redemption Price
         ------                                                             ----------------
<S>                                                                         <C>
     Beginning on February 20, 2003 and ending on February 14,2004............. 102.429%

     Beginning on February 15, 2004 and ending on February 14, 2005.............101.821

     Beginning on February 15, 2005 and ending on February 14, 2006.............101.214

     Beginning on February 15, 2006 and ending on February 14, 2007.............100.607
</TABLE>

                                      A-6
<PAGE>   93
and 100% on February 15, 2007; provided, however, that if the date fixed for
redemption is on a February 15 or August 15, then the interest payable on such
date shall be paid to the holder of record on the preceding February 1 or August
1, respectively.

                  The Company may not give notice of any redemption of the Notes
if a default in the payment of interest or premium, if any, on the Notes has
occurred and is continuing.

                  The Notes are not subject to redemption through the operation
of any sinking fund.

                  If a Fundamental Change occurs at any time prior to maturity
of the Notes, the Notes will be redeemable on the 30th day after notice thereof
(the "Repurchase Date") at the option of the holder of the Notes at a redemption
price equal to 100% of the principal amount thereof, together with accrued
interest to (but excluding) the date of redemption; provided, however, that, if
such Repurchase Date is a February 15 or August 15, the interest payable on such
date shall be paid to the holder of record of the Notes on the preceding
February 1 or August 1, respectively. The Notes will be redeemable in multiples
of $1,000 principal amount. The Company shall mail to all holders of record of
the Notes a notice of the occurrence of a Fundamental Change and of the
redemption right arising as a result thereof on or before the 10th day after the
occurrence of such Fundamental Change. For this Note to be so redeemed at the
option of the holder, the Company must receive at the office or agency of the
Company maintained for that purpose in accordance with the terms of the
Indenture, this Note with the form entitled "Option to Elect Repayment Upon a
Fundamental Change" on the reverse hereof duly completed, together with this
Note, duly endorsed for transfer, on or before the 30th day after the date of
such notice of a Fundamental Change (or if such 30th day is not a Business Day,
the immediately succeeding Business Day).

                  Subject to the provisions of the Indenture, the holder hereof
has the right, at its option, at any time after the original issuance of any
Notes through the close of business on the final maturity date of the Notes, or,
as to all or any portion hereof called for redemption, prior to the close of
business on the Business Day immediately preceding the date fixed for redemption
(unless the Company shall default in payment due upon redemption thereof), to
convert the principal hereof or any portion of such principal which is $1,000 or
an integral multiple thereof into that number of shares of the Company's Common
Stock (as such shares shall be constituted at the date of conversion) obtained
by dividing the principal amount of this Note or portion thereof to be converted
by the Conversion Price of $57.78, as may adjusted from time to time as provided
in the Indenture, upon surrender of this Note, together with a conversion notice
as provided in the Indenture (the form entitled "Conversion Notice" on the
reverse hereof), to the Company at the office or agency of the Company
maintained for that purpose in accordance with the terms of the Indenture, or at
the option of such holder, the Corporate Trust Office, and, unless the shares
issuable on conversion are to be issued in the same name as this Note, duly
endorsed by, or accompanied by instruments of transfer in form satisfactory to
the Company duly executed by, the holder or by his duly authorized attorney. No
adjustment in respect of interest on any Note converted or dividends on any
shares issued upon conversion of such Note will be made upon any conversion
except as set forth in the next sentence. If this Note (or portion hereof) is
surrendered for conversion during the period from the close of business on any
record date for the payment of interest to the close of business on the Business
Day preceding the following

                                      A-7

<PAGE>   94
interest payment date and either (x) has not been called for redemption on a
redemption date that occurs during such period or (y) is not to be redeemed in
connection with a Fundamental Change on a Repurchase Date that occurs during
such period, this Note (or portion hereof being converted) must be accompanied
by an amount, in New York Clearing House funds or other funds acceptable to the
Company, equal to the interest payable on such interest payment date on the
principal amount being converted; provided, however, that no such payment shall
be required if there shall exist at the time of conversion a default in the
payment of interest on the Notes. No fractional shares will be issued upon any
conversion, but an adjustment and payment in cash will be made, as provided in
the Indenture, in respect of any fraction of a share which would otherwise be
issuable upon the surrender of any Note or Notes for conversion. A Note in
respect of which a holder is exercising its right to require redemption upon a
Fundamental Change may be converted only if such holder withdraws its election
to exercise such right in accordance with the terms of the Indenture. Any Notes
called for redemption, unless surrendered for conversion by the holders thereof
on or before the close of business on the Business Day preceding the date fixed
for redemption, may be deemed to be redeemed from the holders of such Notes for
an amount equal to the applicable redemption price, together with accrued but
unpaid interest (including Liquidated Damages, if any) to (but excluding) the
date fixed for redemption, by one or more investment banks or other purchasers
who may agree with the Company (i) to purchase such Notes from the holders
thereof and convert them into shares of the Company's Common Stock and (ii) to
make payment for such Notes as aforesaid to the Trustee in trust for the
holders.

                  Upon due presentment for registration of transfer of this Note
at the office or agency of the Company maintained for that purpose in accordance
with the terms of the Indenture, a new Note or Notes of authorized denominations
for an equal aggregate principal amount will be issued to the transferee in
exchange thereof; subject to the limitations provided in the Indenture, without
charge except for any tax, assessment or other governmental charge imposed in
connection therewith.

                  The Company, the Trustee, any authenticating agent, any paying
agent, any conversion agent and any Note registrar may deem and treat the
registered holder hereof as the absolute owner of this Note (whether or not this
Note shall be overdue and notwithstanding any notation of ownership or other
writing hereon made by anyone other than the Company or any Note registrar) for
the purpose of receiving payment hereof, or on account hereof, for the
conversion hereof and for all other purposes, and neither the Company nor the
Trustee nor any other authenticating agent nor any paying agent nor other
conversion agent nor any Note registrar shall be affected by any notice to the
contrary. All payments made to or upon the order of such registered holder
shall, to the extent of the sum or sums paid, satisfy and discharge liability
for monies payable on this Note.

                  No recourse for the payment of the principal of or any premium
or interest on this Note, or for any claim based hereon or otherwise in respect
hereof, and no recourse under or upon any obligation, covenant or agreement of
the Company in the Indenture or any supplemental indenture or in any Note, or
because of the creation of any indebtedness represented thereby, shall be had
against any incorporator, stockholder, employee, agent, officer or director or
subsidiary, as such, past, present or future, of the Company or of any successor
corporation, either directly or through the Company or any successor
corporation, whether by virtue of any constitution, statute or rule of law or by
the enforcement of any assessment or
                                      A-8
<PAGE>   95
penalty or otherwise, all such liability being, by acceptance hereof and as part
of the consideration for the issue hereof, expressly waived and released.

                  This Note shall be deemed to be a contract made under the laws
of New York, and for all purposes shall be construed in accordance with the laws
of New York, without regard to principles of conflicts of laws.

                  Terms used in this Note and defined in the Indenture are used
herein as therein defined.

                                      A-9
<PAGE>   96
                                  ABBREVIATIONS

                  The following abbreviations, when used in the inscription of
the face of this Note, shall be construed as though they were written out in
full according to applicable laws or regulations.

                  TEN COM - as tenants in common UNIF GIFT MIN ACT - _____
Custodian _____ TEN ENT - as tenant by the entireties (Cust)

                  (Minor) JT TEN - as joint tenants with right of survivorship
and not as under Uniform Gifts to Minors Act tenants in common
________________________________ (State)

                  Additional abbreviations may also be used though not in the
above list.


                                      A-10
<PAGE>   97
                                CONVERSION NOTICE

TO:      BURR-BROWN CORPORATION
                  UNITED STATES TRUST COMPANY OF NEW YORK


                  The undersigned registered owner of this Note hereby
irrevocably exercises the option to convert this Note, or the portion thereof
(which is $1,000 or an integral multiple thereof) below designated, into shares
of Common Stock of Burr-Brown Corporation in accordance with the terms of the
Indenture referred to in this Note, and directs that the shares issuable and
deliverable upon such conversion, together with any check in payment for
fractional shares and any Notes representing any unconverted principal amount
hereof, be issued and delivered to the registered holder hereof unless a
different name has been indicated below. If shares or any portion of this Note
not converted are to be issued in the name of a person other than the
undersigned, the undersigned will provide the appropriate information below and
pay all transfer taxes payable with respect thereto. Any amount required to be
paid by the undersigned on account of interest accompanies this Note.

Dated:

-----------------------------

-----------------------------

-----------------------------
Signature(s)

         Signature(s) must be guaranteed by an "eligible guarantor institution"
         meeting the requirements of the Note registrar, which requirements
         include membership or participation in the Security Transfer Agent
         Medallion Program ("STAMP") or such other "signature guarantee program"
         as may be determined by the Note registrar in addition to, or in
         substitution for, STAMP, all in accordance with the Securities Exchange
         Act of 1934, as amended.

-------------------------------
Signature Guarantee
                                      A-11
<PAGE>   98
                  Fill in the registration of shares of Common Stock if to be
issued, and Notes if to be delivered, other than to and in the name of the
registered holder:

 -------------------------------------
(Name)

 -------------------------------------
(Street Address)

 -------------------------------------
(City, State and Zip Code)

 -------------------------------------
Please print name and address

Principal amount to be converted (if less than all):


$
 ------------------------------------
Social Security or Other Taxpayer
Identification Number:

 -------------------------------------

                                      A-12
<PAGE>   99

                            OPTION TO ELECT REPAYMENT

                            UPON A FUNDAMENTAL CHANGE

TO:   BURR-BROWN CORPORATION
      UNITED STATES TRUST COMPANY OF NEW YORK

                  The undersigned registered owner of this Note hereby
irrevocably acknowledges receipt of a notice from Burr-Brown Corporation (the
"Company") as to the occurrence of a Fundamental Change with respect to the
Company and requests and instructs the Company to repay the entire principal
amount of this Note, or the portion thereof (which is $1,000 or an integral
multiple thereof) below designated, in accordance with the terms of the
Indenture referred to in this Note at the price of 100% of such entire principal
amount or portion thereof, together with accrued interest to, but excluding,
such repayment date, to the registered holder hereof.

Dated:
---------------------------

---------------------------

---------------------------
Signature(s)

                                    NOTICE: The above signatures of the
                                    holder(s) hereof must correspond with the
                                    name as written upon the face of the Note in
                                    every particular without alteration or
                                    enlargement or any change whatever.
                                    Principal amount to be repaid (if less than
                                    all):
                                   $
                                    ---------------------------------
                                    ----------------------------------
                                    Social Security or Other Taxpayer
                                    Identification Number

                                      A-13
<PAGE>   100


                                   ASSIGNMENT

                  For value received____________________________________
hereby sell(s) assign(s) and transfer(s) unto___________________________
_________________________________ (Please insert social security or other
Taxpayer Identification Number of assignee) the within Note, and hereby
irrevocably constitutes and appoints ____________________________________
attorney to transfer said Note on the books of the Company, with full power of
substitution in the premises.

                  In connection with any transfer of the Note prior to the
expiration of the holding period applicable to sales thereof under Rule 144(k)
under the Securities Act (or any successor provision) (other than any transfer
pursuant to a registration statement that has been declared effective under the
Securities Act), the undersigned confirms that such Note is being transferred:

[ ]     To Burr-Brown Corporation or a subsidiary thereof; or

[ ]     Inside the United States pursuant to and in compliance with Rule 144A
        under the Securities Act of 1933, as amended; or

[ ]     Inside the United States to an Institutional Accredited Investor
        pursuant to and in compliance with the Securities Act of 1933, as
        amended; or

[ ]     Outside the Unites States in compliance with Rule 904 under the
        Securities Act; or

[ ]     Pursuant to and in compliance with Rule 144 under the Securities Act of
        1933, as amended;

and unless the box below is checked, the undersigned confirms that such Note is
not being transferred to an "affiliate" of the Company as defined in Rule 144
under the Securities Act of 1933, as amended (an "Affiliate").

                  [ ]      The transferee is an Affiliate of the Company.

Dated:
---------------------
                                  ---------------------
                                  ---------------------
                                  Signature(s)

                                  Signature(s) must be guaranteed by an
                                  "eligible guarantor institution" meeting the
                                  requirements of the Note registrar, which
                                  requirements include membership or
                                  participation in the Security Transfer Agent
                                  Medallion Program ("STAMP") or such other
                                  "signature guarantee program" as may be
                                  determined by the Note registrar in addition
                                  to, or in substitution for, STAMP, all in
                                  accordance with the Securities Exchange Act
                                  of 1934, as amended.


                                  -----------------------------------
                                  Signature Guarantee

                                  A-14
<PAGE>   101

NOTICE: The signature of the conversion notice, the option to elect repayment
upon a Fundamental Change or the assignment must correspond with the name as
written upon the face of the Note in every particular without alteration or
enlargement or any change whatever.

                                      A-15
<PAGE>   102
                                    EXHIBIT B

Burr-Brown Corporation
6730 South Tucson Boulevard
Tucson, Arizona 85706

United States Trust Company of New York
as Trustee
114 W. 47th Street
New York, New York 10036-1532
Attention:  Corporate Trust Administration

Ladies and Gentlemen:

         In connection with our proposed purchase of 4 1/4% Convertible
Subordinated Notes due 2007 (the "Notes") of Burr-Brown Corporation, a Delaware
corporation (the "Company") we confirm that:

         (i) we are an "accredited investor" within the meaning of Rule
501(a)(1), (2), (3) or (7) under the Securities Act of 1933, as amended (the
"Securities Act"), or an entity in which all of the equity owners are accredited
investors within the meaning of Rule 501(a)(1), (2), (3) or (7) under the
Securities Act (an "Institutional Accredited Investor");

         (ii) (A) any purchase of Notes by us will be for our own account or for
the account of one or more other Institutional Accredited Investors or as
fiduciary for the account of one or more trusts, each of which is an "accredited
investor" within the meaning of Rule 501(a)(7) under the Securities Act and for
each of which we exercise sole investment discretion or (B) we are a "bank,"
within the meaning of Section 3(a)(2) of the Securities Act, or a "savings and
loan association" or other institution described in Section 3(a)(5)(A) of the
Securities Act that is acquiring Notes as fiduciary for the account of one or
more institutions for which we exercise sole investment discretion;

         (iii) in the event that we purchase any Notes, we will acquire Notes
having a minimum purchase price of not less than $100,000 for our own account or
for any separate account for which we are acting;

         (iv) we have such knowledge and experience in financial and business
matters that we are capable of evaluating the merits and risks of purchasing
Notes; and

         (v) we are not acquiring Notes with a view to distribution thereof or
with any present intention of offering or selling Notes or the Common Stock of
the Company issuable upon conversion thereof, except as permitted below;
provided that the disposition of our property and property of any accounts for
which we are acting as fiduciary shall remain at all times within our control.

         We understand that the Notes are being offered in a transaction not
involving any public offering within the United States within the meaning of the
Securities Act and that the

                                   B-1
<PAGE>   103
Notes and the Common Stock of the Company issuable upon conversion thereof have
not been registered under the Securities Act, and we agree, on our own behalf
and on behalf of each account for which we acquire any Notes, that if in the
future we decide to resell or otherwise transfer such Notes or the Common Stock
of the Company issuable upon conversion thereof, such Notes or Common Stock of
the Company may be resold or otherwise transferred only (i) to the Company or
any subsidiary thereof, (ii) inside the United States to a person who is a
"qualified institutional buyer" (as defined in Rule 144A under the Securities
Act) in a transaction meeting the requirements of Rule 144A, (iii) inside the
United States to an Institutional Accredited Investor that, prior to such
transfer, furnishes to the Trustee for the Notes (or in the case of Common Stock
of the Company, the transfer agent therefor) a signed letter containing certain
representations and agreements relating to the restrictions on transfer of such
securities (the form of which letter can be obtained from the Trustee or the
transfer agent, as the case may be), (iv) outside the United States in a
transaction meeting the requirements of Rule 904 under the Securities Act,
(v)pursuant to the exemption from registration provided by Rule 144 under the
Securities Act (if applicable), or (vi) pursuant to a registration statement
that has been declared effective under the Securities Act (and which continues
to be effective at the time of such transfer), and in each case, in accordance
with any applicable securities law of any state of the United States and in
accordance with the legends set forth on the Notes or the Common Stock of the
Company issuable upon conversion thereof. We further agree to provide any person
purchasing any of the Notes or the Common Stock of the Company issuable upon
conversion thereof (other than pursuant to clause (v) or (vi) above or pursuant
to Rule 144(k)) from us a notice advising such purchaser that resales of such
securities are restricted as stated herein. We understand that the Trustee and
transfer agent for the Notes and the Common Stock of the Company will not be
required to accept for registration of transfer any Notes or any Common Stock of
the Company issued upon conversion of the Notes, except upon presentation of
evidence satisfactory to the Company that the foregoing restrictions on transfer
have been complied with. We further understand that any Notes and any Common
Stock of the Company issued upon conversion of the Notes will be in the form of
definitive physical certificates and that such certificates will bear a legend
reflecting the substance of this paragraph other than certificates transferred
pursuant to (v) or (vi) above, or pursuant to Rule 144(k).

                  The Company and the Trustee and their respective counsel are
entitled to rely upon this letter and are irrevocably authorized to produce this
letter or a copy hereof to any interested party in any administrative or legal
proceeding or official inquiry with respect to the matters covered hereby.

                  THIS LETTER SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK.

                                                   (Name of Purchaser)

                                                   By:
                                                    --------------------------
                                                   Name:
                                                     --------------------------
                                                   Title:
                                                     --------------------------
                                                   Address:
                                                     --------------------------

                                                     --------------------------


                                      B-2