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                                                                   Exhibit 10.45
                                                                   -------------

                         REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement (this "Agreement") is made and entered
into as of December 8, 2000, by and between RF Monolithics, Inc., a Delaware
corporation (the "Company"), and Wells Fargo Business Credit, Inc., a Minnesota
corporation, as the purchaser of the Warrants (the "Initial Holder").

     For good and valuable consideration, the receipt and adequacy of which are
hereby acknowledged, the parties hereby agree as follows:

     1.   Definitions. As used in this Agreement, the following capitalized
          -----------
terms shall have the following meanings:

     Agreement: This Registration Rights Agreement, as amended and modified from
time to time.

     Company: RF Monolithics, Inc., a Delaware corporation and its successors
and assigns.

     Common Stock: The common stock, $.001 par value, of the Company or any
shares of any class or classes resulting from any reclassification or
reclassifications thereof and which have no preferences 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 that are not subject to redemption.

     Demand Registration: A registration of the Registrable Securities described
in Section 2.1.

     Exchange Act: Securities Exchange Act of 1934, as from time to time
amended.

     Holder: The Initial Holder and any Person that holds any Warrants or any
Registrable Securities.

     Initial Holder: Wells Fargo Business Credit, Inc. as the initial purchaser
of the Warrants.

     Misstatement: An untrue statement of a material fact or an omission to
state a material fact required to be stated in a Registration Statement,
Prospectus or preliminary prospectus necessary to make the statements in a
Registration Statement, Prospectus or preliminary prospectus not misleading.

     Other Holders: Holders of Other Registrable Securities in such capacity.

     Other Registrable Securities: (a) any shares of Common Stock that are not
Registrable Securities but that are the subject of an effective agreement with
the Company according registration rights to the holders of such stock,
including "Registrable Securities" as defined in the Unitholder Registration
Rights Agreement and (b) any securities issued or issuable with respect to any
Common Stock referred to in the foregoing clause by way of stock dividend or

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stock split or in connection with a combination of shares, recapitalization,
merger, consolidation or other reorganization or otherwise.

     Person: A natural person, partnership, corporation, business trust,
association, joint venture or other entity or a government or agency or
political subdivision thereof.

     Piggyback Registration: A registration of the Registrable Securities
described in Section 2.2 hereof.

     Prospectus: The prospectus included in any Registration Statement, as
supplemented by any and all prospectus supplements and as amended by any and all
post-effective amendments and including all material incorporated by reference
in such prospectus.

     Registrable Securities: (a) The shares of Common Stock acquired by the
Holders or their permitted assigns in connection with the exercise of the
Warrants, and (b) any securities issued or issuable with respect to such Common
Stock by way of a stock dividend or stock split or in connection with a
combination of shares, recapitalization, merger, consolidation or
reorganization; provided that any such share or security shall be deemed to be
Registrable Securities only if and so long as it (i) has not been sold such
securities to or through a broker, dealer or underwriter in a public
distribution or other public securities transaction or sold in a transaction
exempt from the registration and prospectus delivery requirements of the
Securities Act under Rule 144(k) promulgated thereunder (or any successor rule
other than Rule 144A) or (ii), along with all other shares of Common Stock owned
by the Holder and all securities issued or issuable with respect to such Common
Stock by way of a stock dividend or stock split or in connection with a
combination of shares, recapitalization, merger, consolidation or reorganization
are not eligible for immediate sale in a transaction exempt from the
registration and prospectus delivery requirements of the Securities Act under
Rule 144(k) promulgated thereunder (or any successor rule other than Rule 144A)
and all restrictive legends have been removed from the certificates representing
such securities, there are no stop transfer orders on the transfer books with
respect to such securities and the securities are not subject to any
"underwriter lock-ups" or other similar restrictions.

     Registration: A Demand Registration described in Section 2.1 and a
Piggyback Registration described in Section 2.2 and an "S-3" registration
described in Section 2.4.

     Registration Expenses: The out-of-pocket expenses of a Registration,
including:

          (1)  all registration and filing fees (including fees with respect to
     filings required to be made with the National Association of Securities
     Dealers, Inc. and any securities exchange on which the Common Stock is then
     listed);

          (2)  fees and expenses of compliance with securities or blue sky laws
     (including reasonable fees and disbursements of counsel for the
     underwriters in connection with blue sky qualifications of the Registrable
     Securities);

          (3)  printing, messenger, telephone and delivery expenses;

          (4)  reasonable fees and disbursements of counsel for the Company;

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          (5)  reasonable fees and disbursements of one law firm, selected by
     the selling Holders registering the majority of the Registrable Securities
     in any given Registration, acting as counsel for the Selling Holders;

          (6)  reasonable fees and disbursements of all independent certified
     public accountants of the Company incurred specifically in connection with
     such Registration; and

          (7)  all other reasonable fees and expenses (other than underwriting
     discounts and commissions relating to Registrable Securities) incurred in
     connection with a Registration, whether or not such Registration becomes
     effective.

     Registration Statement: Any registration statement that covers Registrable
Securities pursuant to the provisions of this Agreement, including the
Prospectus included in such registration statement, amendments (including post-
effective amendments) and supplements to such registration statement, and all
exhibits to and all material incorporated by reference in such registration
statement.

     Requesting Holders:  Has the meaning ascribed to it in Section 2.1.

     Securities Act: The Securities Act of 1933, as from time to time amended.

     SEC: The Securities and Exchange Commission and any successor agency
thereto.

     Warrant Agreement: The Warrant Agreement, dated as of even date herewith,
to which the Company and the Initial Holder are parties and pursuant to which
the Company issued the Warrants.

     Warrants: The warrants issued pursuant to the Warrant Agreement.

     Underwritten Registration or Underwritten Offering: A Registration in which
securities of the Company are sold to an underwriter for distribution to the
public pursuant to a firm commitment underwriting.

     Unitholder Registration Rights Agreement: The Registration Rights Agreement
dated as of the date hereof, by and among the Company and the and certain
investors named therein pertaining to the purchase of 533,332 shares of Common
Stock and 533,332 warrants to purchase Common Stock.

     2.   Registrations.

          2.1  Demand Registration.  If, at any time after the date hereof,
               -------------------
     the Company shall receive from the Holders (the "Requesting Holders")
     owning as of the date of such request at least 50% of the then outstanding
     shares of Registrable Securities a written request to register at least 30%
     of the Registrable Securities owned by such Holders as of the date of such
     request, then the Company will promptly give notice of such request to all
     Holders and shall effect as soon thereafter as practicable, and in any
     event within 90 days of the receipt of such request, the Registration under
     the Securities Act of all

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     Registrable Securities which any Holder requests to be registered.
     Notwithstanding the foregoing, the Company shall not be under any
     obligation to have a Demand Registration become effective prior to a date
     earlier than six (6) months following the date hereof. Further, the Company
     shall not be obligated to effect, or to take any action to effect, a Demand
     Registration if Requesting Holders request that the Demand Registration to
     be filed is during the period starting with the date (determined at the
     time such request for Demand Registration is made) thirty (30) days prior
     to the Company's good faith estimate of the date of filing of, and ending
     on a date one hundred eighty (180) days after the effective date of, a
     Company-initiated underwritten Registration in which the Holders may
     participate as to at least forty percent (40%) of the Registrable
     Securities held by each of them pursuant to Section 2.2; provided that the
     Company is actively employing in good faith all reasonable efforts to cause
     such Registration Statement to become effective.

     The Holders shall not be entitled to more than one (1) Demand Registration.
     However, any Demand Registration that does not become effective, or if any
     offering associated with a Demand Registration is not able to close,
     through no fault of the Holders and no other person, such Demand
     Registration shall not be deemed to be the Demand Registration to which the
     Holders are entitled.

          2.2  Piggyback Registration.  Each time the Company decides to file a
               ----------------------
     Registration Statement under the Securities Act (other than on Forms S-4 or
     S-8 or any successor form for the registration of securities issued or to
     be issued in connection with a merger or acquisition or employee benefit
     plan), the Company shall give written notice thereof to the Holders. The
     Company shall include in such Registration Statement such shares of
     Registrable Securities for which it has received written requests to
     register such shares within fifteen (15) days after such written notice has
     been given. If in the good faith judgment of the managing underwriter in
     any Underwritten Offering, the inclusion of all of the shares of
     Registrable Securities and any other Common Stock requested to be
     registered by third parties holding similar registration rights would
     materially interfere with the successful marketing of a smaller number of
     such shares, then the number of shares of Registrable Securities and other
     Common Stock to be included in the offering (except for shares to be issued
     by the Company in an offering initiated by the Company) shall be reduced as
     provided herein. The Company shall advise all holders of securities
     requesting registration of the underwriters' decision; and the number of
     shares of securities that are entitled to be included in the Underwritten
     Registration shall be allocated first to the Company for securities being
     sold for its own account and thereafter as set forth in Section 2.3 below.
     If any Person does not agree to the terms of any such underwriting, such
     Person shall be excluded therefrom by written notice from the Company or
     the underwriter. Any Registrable Securities or other shares of Common Stock
     excluded or withdrawn from such underwriting shall be withdrawn from such
     registration. If shares are so withdrawn from the registration or if the
     number of shares of Registrable Securities to be included in such
     registration was previously reduced as a result of marketing factors, the
     Company shall then offer to all Persons who have retained the right to
     include securities in the registration the right to include additional
     securities in the registration in an aggregate amount equal to the number
     of shares so withdrawn,

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     with such shares to be allocated among the Persons, requesting additional
     inclusion in accordance with Section 2.3 below.

          2.3  Underwriter Cutback.
               -------------------

               (a)  If a Demand Registration involves an Underwritten Offering,
          and the managing underwriter advises the Company in writing (with a
          copy to each Holder requesting Registration) that, in its opinion, the
          number of Registrable Securities and other securities of the Company
          held by any other Person requested to be included in such Registration
          exceeds the number which can be sold in (or during the time of) such
          offering within a price range acceptable to the holders of a majority
          (by number of shares) of the Registrable Securities requested to be
          included in such Registration, the Company will include in such
          Registration all Registrable Securities requested to be included in
          such Registration (unless the provisions of the following sentence
          apply) and will include in such Registration other securities of the
          Company held by any other Person (including any securities proposed to
          be issued and sold by the Company) only to the extent that the number
          of shares that the Company is advised can be so sold in (or during the
          time of) such offering exceeds the number of Registrable Securities to
          be included in such Registration. If a Demand Registration involves an
          Underwritten Offering, and the managing underwriter advises the
          Company in writing (with a copy to each Holder requesting
          registration) that, in its opinion, the number of Registrable
          Securities requested to be included in such Registration exceeds the
          number which can be sold in (or during the time of) such Underwritten
          Offering within a price range acceptable to the holders of a majority
          (by number of shares) of the Registrable Securities requested to be
          included in such registration, the Company will include in such
          Registration only Registrable Securities requested to be included in
          such Registration. In such event, such Registrable Securities will be
          included in such Registration only to the extent of the number of
          shares which the Company is advised can be so sold in (or during the
          time of) such Underwritten Offering; the Registrable Securities to be
          included in such registration shall be taken up pro rata from the
          holders of Registrable Securities requesting such Registration on the
          basis of the percentage of Registrable Securities requested to be
          included in such Registration; and all shares proposed to be sold by
          the Company or any other party shall be deleted from such Registration
          prior to effecting any reduction of Registrable Securities by the
          holders thereof under this paragraph (a). In the event that less than
          all of the Registrable Securities requested to be included in a Demand
          Registration are not included in such Demand Registration as a result
          of an underwriter cutback pursuant to the provisions of this Section
          2.3, such Demand Registration shall not be deemed the Demand
          Registration to which the Holders are entitled.

               (b)  If (i) a Piggy-Back Registration involves an Underwritten
          Offering of the securities so being registered, whether or not for
          sale for the account of the Company, and (ii) the managing underwriter
          of such Underwritten Offering shall inform the Company and the holders
          of the Registrable Securities requesting such Registration by letter
          of its belief that the number of securities requested to be

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          included in such Registration exceeds the number which can be sold in
          (or during the time of) such offering, then (A) in the case of an
          Underwritten Offering for the account of the Company, Registration for
          the Registrable Securities shall be cut back such that (1) no holder
          of Registrable Securities shall be entitled to participate in such
          Underwritten Offering unless all shares of Common Stock proposed to be
          sold by the Company for its own account have been included in such
          Underwritten Offering, and (2) after the Company has included its own
          shares of Common Stock, the Holders and Other Holders shall be
          entitled to include their Registrable Securities and Other Registrable
          Securities in an amount up to the amount that such managing
          underwriter or underwriters advise may be included therein (allocated
          among the Holders and Other Holders pro rata on the basis of the
          number of Registrable Securities and Other Registrable Securities
          requested to be included therein by each such holder) and (B) in the
          case of an Underwritten Offering that was commenced as a result of the
          exercise of demand registration rights by Other Holders, the Other
          Holders commencing such Registration and the Holders shall be entitled
          to include their Other Registrable Securities and Registrable
          Securities in an amount up to the amount such managing underwriters or
          underwriters advise may be included therein (allocated first to the
          Other Holders commencing such Registration and thereafter among the
          Holders and Other Holders who did not commence such Registration). If,
          however, the Registration was initiated by the Company within one
          hundred twenty (120) days of a Demand Registration and is in lieu
          thereof, then the Company shall include in the registration all
          Registrable Securities or Other Registrable Securities requested to be
          included in such Registration and shall decrease the number of
          securities proposed to be sold by the Company and to be included in
          such Registration to the extent necessary to reduce the number of
          securities to be included in the Registration to the level recommended
          by the managing underwriter.

          2.4  Registration.  At any time the Company is eligible to file a
               ------------
registration statement on Form S-3 (or any such successor form relating to
secondary offerings), Holders holding a majority of the Registrable Securities
then outstanding may request the Company, in writing, to effect the registration
on Form S-3 (or such successor form) and any related qualification or compliance
with respect to all or a part of the Registrable Securities held by such
Holders. Upon receipt of such notice, then the Company shall, promptly after the
receipt thereof, give written notice of such request to all Holders.
Notwithstanding the foregoing, the Company shall not be under any obligation
under this Section 2.4 if (i) the aggregate fair market value of the Registrable
Securities to be registered on the date of such request is made does not equal
or exceed $500,000 or (ii) to effect an underwritten or dealer-managed offering.
The Company shall use its best efforts to effect such a registration as soon as
practicable, covering all the Registrable Securities which the Holders shall
request in writing within twenty (20) days after receipt of such notice. The
Company shall use its best efforts to cause such registration statement to
become effective; provided, however, that the Company shall not be obligated to
effect any such registration, qualification or compliance pursuant to this
Section 2.4 if Form S-3 (or any such successor form relating to secondary
offerings) is not available for such offering by the Holders.

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          2.5  Postponement.  The Company may postpone the filing of any
               ------------
     Registration Statement required hereunder for a reasonable period of time,
     not to exceed ninety (90) days in the aggregate during any twelve-month
     period, if the Company has been advised by legal counsel that such filing
     would require a special audit or the disclosure of a material impending
     transaction or other matter and the Company's Board of Directors determines
     reasonably and in good faith that such disclosure would have a material
     adverse effect on the Company; provided, however, that the Company shall
     use its best efforts to achieve such effectiveness promptly following such
     period.

     3.   Registration Procedures.  If and whenever the Company is required to
          -----------------------
register Registrable Securities, the Company will use its best efforts to effect
such registration to permit the sale of such Registrable Securities in
accordance with the intended plan of distribution thereof, and pursuant thereto
the Company will as expeditiously as possible:

               (a)  prepare and file with the SEC as soon as practicable a
          Registration Statement with respect to such Registrable Securities and
          use its best efforts to cause such Registration Statement to become
          effective and remain effective until the Registrable Securities
          covered by such Registration Statement have been sold;

               (b)  prepare and file with the SEC such amendments and post-
          effective amendments to the Registration Statement, and such
          supplements to the Prospectus, as may be requested by the Holders or
          any underwriter of Registrable Securities or as may be required by the
          rules, regulations or instructions applicable to the registration form
          used by the Company or by the Securities Act or rules and regulations
          thereunder to keep the Registration Statement effective until all
          Registrable Securities covered by such Registration Statement are sold
          in accordance with the intended plan of distribution set forth in such
          Registration Statement or supplement to the Prospectus;

               (c)  deliver to the Holders, their attorneys and the
          underwriters, if any, without charge, as many copies of each
          Prospectus (and each preliminary prospectus) as such Persons may
          reasonably request (the Company hereby consenting to the use of each
          such Prospectus (or preliminary prospectus) by the selling Holders and
          the underwriters, if any, in connection with the offering and sale of
          the Registrable Securities covered by such Prospectus (or preliminary
          prospectus) and a reasonable number of copies of the then-effective
          Registration Statement and any post-effective amendments thereto and
          any supplements to the Prospectus, including financial statements and
          schedules, all documents incorporated therein by reference and all
          exhibits (including those incorporated by reference);

               (d)  prior to any public offering of Registrable Securities,
          register or qualify or cooperate with the Holders, the underwriters,
          if any, and their respective counsel in connection with the
          registration or qualification of such Registrable Securities for offer
          and sale under the securities or blue sky laws of such jurisdictions
          as such selling Holders or underwriters may designate in writing and
          do anything else necessary or advisable to enable the disposition in

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          such jurisdictions of the Registrable Securities covered by the
          Registration Statement; provided that the Company shall not be
          required to qualify generally to do business in any jurisdiction where
          it is not then so qualified or to take any action which would subject
          it to general service of process in any such jurisdiction where it is
          not then so subject;

               (e)  cause all such Registrable Securities to be listed on each
          securities exchange, stock market or automated quotation system on
          which similar securities issued by the Company are then listed;

               (f)  provide a transfer agent and registrar for all such
          Registrable Securities not later than the effective date of such
          Registration Statement;

               (g)  advise each seller of such Registrable Securities, promptly
          after it shall receive notice or obtain knowledge thereof, of the
          issuance of any stop order by the SEC suspending the effectiveness of
          such Registration Statement or the initiation or threatening of any
          proceeding for such purpose and promptly use its reasonable best
          efforts to prevent the issuance of any stop order or to obtain its
          withdrawal if such stop order should be issued;

               (h)  at least three days prior to the filing of any Registration
          Statement or prospectus or any amendment or supplement to such
          Registration Statement or prospectus or any document that is to be
          incorporated by reference into such Registration Statement or
          prospectus, furnish a copy thereof to each seller of such Registrable
          Securities or their counsel;

               (i)  notify the Holders at any time when a prospectus relating to
          such Registration Statement is required to be delivered under the
          Securities Act, of the happening of any event as a result of which the
          prospectus included in such Registration Statement, as then in effect,
          includes a Misstatement, and then to correct such Misstatement as set
          forth in Section 8; and

               (j)  permit a representative of the Holders, the underwriters, if
          any, and any attorney or accountant retained by such Holders or
          underwriter to participate in the preparation of the Registration
          Statement, and cause the Company's officers, directors and employees
          to supply all information reasonably requested by any such
          representative, underwriter, attorney or accountant in connection with
          the Registration; provided, however, that such representatives,
          underwriters, or accountants enter into a confidentiality agreement,
          in form and substance reasonably satisfactory to the Company, prior to
          the release or disclosure of any such information.

     4.   Registration Expenses.  The Registration Expenses of all Registrations
          ---------------------
shall be borne by the Company. It is acknowledged by the Holders that the
Holders will bear all underwriters' commissions and discounts relating to the
sale of the Registrable Securities.

     5.   Requirements of Participation in Underwritten Offerings.  No Person
          -------------------------------------------------------
may participate in any Underwritten Offering for equity securities of the
Company pursuant to a

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Registration initiated by the Company hereunder unless such Person (a) agrees to
sell such Person's securities on the basis provided in any underwriting
arrangements approved by the Company (provided, the underwriting agreement is no
less favorable to such Person than it is to the Company) and (b) completes and
executes all questionnaires, powers of attorney, indemnities, lock-up
agreements, such underwriting agreements and other documents reasonably required
under the terms of such underwriting arrangements.

     6.   Other Registrations.

               (a)  The Company may not cause any other registration of
          securities for sale for its own account (other than a registration
          effected solely to implement an employee benefit plan) to be initiated
          after a Demand Registration and to become effective less than ninety
          (90) days after the effective date of any such Demand Registration.

               (b)  The Company shall not, without the prior written consent of
          the Holders holding the majority of Registrable Securities, enter into
          any agreement with any holder or prospective holder of any securities
          of the Company that would allow such holder or prospective holder to
          include any securities in any registration filed under Sections 2
          unless, under the terms of such agreement, such holder or prospective
          holder may include such securities in any such registration only to
          the extent that the inclusion of such securities will not reduce the
          amount of Registrable Securities to be included by the Holders or the
          Company in the Demand Registration and shall grant the Holders rights
          comparable to those rights granted to the Company under Section 2.3.

               (c)  The Company represents and warrants that: (i) no Person has
          any registration rights other than those granted herein; (ii) the
          Company has full power and authority to enter into this Agreement; and
          (iii) this Agreement does not violate or breach any other agreement to
          which the Company is a party. Further the Company covenants that it
          will not grant any Person any registration rights that have any terms
          that are more favorable to such Person than terms and conditions
          contained in this Agreement.

               (d)  Sections 6(b) and 6(c)(i) shall not apply to rights granted
          under Unitholder Registration Rights Agreement.

     7.   Indemnification.
          ---------------

               (a)  The Company agrees to indemnify, to the extent permitted by
          law, the Holders, their officers and directors and each Person who
          controls any such holder (within the meaning of the Securities Act or
          Exchange Act) against all losses, claims, damages, liabilities and
          expenses (including attorneys' fees and expenses) caused by any
          Misstatement or any alleged Misstatement, except insofar as the same
          are caused by or contained in any information furnished in writing to
          the Company by such Holder expressly for use therein or by such
          Holder's failure to deliver a copy of the Registration Statement or
          Prospectus or

                                      -9-
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          any amendments or supplements thereto in a reasonable time period
          after the Company has furnished such holder with a sufficient number
          of copies of the same. The Company will indemnify the underwriters,
          their officers and directors and each Person who controls such
          underwriters (within the meaning of the Securities Act) to the same
          extent as provided above with respect to the indemnification of the
          Holder.

               (b)  In connection with any Registration Statement in which a
          Holder is participating, such Holder will furnish to the Company in
          writing such information and affidavits as the Company reasonably
          requests for use in connection with any such Registration Statement or
          Prospectus and, to the extent permitted by law, will indemnify the
          Company, its directors and officers and agents and each Person who
          controls the Company (within the meaning of the Securities Act or
          Exchange) against any losses, claims, damages, liabilities and
          expenses (including without limitation reasonable attorneys` fees)
          resulting from any Misstatement, but only to the extent that such
          Misstatement is contained in any information or affidavit so furnished
          in writing by such Holder expressly for use therein; provided that the
          obligation to indemnify will be several, not joint and several, among
          such Holders, and the liability of each such holder of Registrable
          Securities will be in proportion to and limited to the gross amount
          received by such holder from the sale or Registrable Securities
          pursuant to such Registration Statement.

               (c)  Any Person entitled to indemnification herein will (i) give
          prompt written notice to the indemnifying party of any claim with
          respect to which it seeks indemnification and (ii) unless in such
          indemnified party's reasonable judgment an actual or potential
          conflict of interest or an actual or potential different interest
          between such indemnified and indemnifying parties may exist with
          respect to such claim, permit such indemnifying party to assume the
          defense of such claim with counsel reasonably satisfactory to the
          indemnified party. If such defense is assumed, the indemnifying party
          will not be subject to any liability for any settlement made by the
          indemnified party without its consent (but such consent will not be
          unreasonably withheld). An indemnifying party who is not entitled to,
          or elects not to, assume the defense of a claim will not be obligated
          to pay the fees and expenses of more than one counsel for all parties
          indemnified by such indemnifying party with respect to such claim,
          unless in the reasonable judgment of any indemnified party an actual
          or potential conflict of interest or an actual or potential different
          interest may exist between such indemnified party and any other of
          such indemnified parties with respect to such claim.

               (d)  The indemnification provided for under this Agreement will
          remain in full force and effect regardless of any investigation made
          by or on behalf of the indemnified party or any officer, director or
          controlling person of such indemnified party and will survive the
          transfer of securities. The Company and each holder of Registrable
          Securities participating in the offering also agrees to make such
          provisions as are reasonably requested by any indemnified party for

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          contribution to such party in the event the Company's or such holder's
          indemnification is unavailable for any reason.

               (e)  The obligations of the Company and the Holders under this
          Section 7 shall survive the completion of any offering of Registrable
          Securities. Notwithstanding the foregoing, to the extent that the
          provisions on indemnification and contribution contained in the
          underwriting agreement entered into in connection with an Underwritten
          Offering are in conflict with the foregoing provisions, the provisions
          of the underwriting agreement shall control.

     8.   Suspension of Sales.  Upon receipt of written notice from the
          -------------------
Company that a Registration Statement or Prospectus contains a Misstatement,
each of the Holders shall forthwith discontinue disposition of Registrable
Securities until it has received copies of a supplemented or amended Prospectus
correcting the Misstatement (it being understood that the Company hereby
covenants to prepare and file such supplement or amendment as soon as
practicable after the time of such notice), or until it is advised in writing by
the Company that the use of the Prospectus may be resumed.

     9.   Restrictions.
          ------------

          9.1  Restrictions on Public Sale by Holder of Registrable Securities.
               ---------------------------------------------------------------
     To the extent not inconsistent with applicable law, each holder of
     Registrable Securities agrees, if requested by the managing underwriter, to
     enter into an agreement with such managing underwriter not to effect any
     public or private sale or distribution of any equity securities of the
     Company, including a sale pursuant to Rule 144 or Rule 144A under the
     Securities Act (except as part of such underwritten registration), during
     the 10-day period prior to, and during the 180-day period beginning on, the
     closing date of each underwritten offering made of the Common Stock to the
     extent timely notified in writing by the Company or the managing
     underwriter; provided, however, such Holder shall not be obligated to enter
     such agreement unless all the executive officers and directors of the
     Company and each holder of the Common Stock who beneficially owns shares of
     the Common Stock equal to or greater than the shares of Common Stock
     beneficially owned by the Holder (including any shares issuable upon the
     exercise of the Warrants) and such Holder has had the opportunity to have
     its shares included in such registration. The foregoing provisions of this
     Section 9.1 shall not apply to any holder of Registrable Securities if such
     holder is prevented by applicable statute or regulation from entering any
     such agreement; provided, however, that any such holder shall undertake, in
     its request to participate in any such underwritten offering, not to effect
     any public sale or distribution of the Registrable Securities commencing on
     the date of sale of such Registrable Securities unless it has provided 45
     days' prior written notice of such sale or distribution to the managing
     underwriter.

          9.2  Restrictions on Sale by the Company and Other Persons.  The
               -----------------------------------------------------
     Company agrees (A) not to effect any public or private sale or distribution
     of any securities substantially similar to the Registrable Securities being
     registered, or any securities convertible into or exchangeable or
     exercisable for such securities, during the 10-day period prior to, and
     during the 20-day period beginning on, the closing date of an

                                      -11-
<PAGE>

     underwritten offering made pursuant to a Demand Registration Statement
     (except as part of such underwritten registration or pursuant to
     registrations on Form S-4 or S-8 or any successor forms) and (B) that any
     agreement pursuant to which the Company issues or agrees to issue any
     privately placed securities shall contain provisions under which holders of
     such securities agree not to effect any public sale or distribution of any
     securities similar to those being registered, or any securities convertible
     into or exchangeable or exercisable for such securities during such period
     (except pursuant to registrations on Form S-4 or S-8).

     10.  Miscellaneous.
          -------------

          10.1 Notices.  All notices and other communications provided for or
               -------
     permitted hereunder shall be made in accordance with the notice provisions
     contained in the Warrant Agreement.

          10.2 Successors and Assigns.  This Agreement shall inure to the
               ----------------------
     benefit of and be binding upon the successors and assigns of the Company.
     The obligations of the Company under this Agreement may be not assigned by
     the Company without the prior written consent of the Holders who hold a
     majority of the Registrable Securities, except to any purchaser of all or
     substantially all of the assets of the Company that assumes the Company's
     obligations hereunder. The Holders may assign or transfer their rights and
     obligations under this Agreement only in connection with the assignment,
     transfer or sale of the Warrants or Registrable Securities.

          10.3 Counterparts.  This Agreement may be executed in any number of
               ------------
     counterparts and by the parties hereto in separate counterparts, each of
     which when so executed shall be deemed to be an original and all of which
     taken together shall constitute one and the same agreement.

          10.4 Governing Law.  This Agreement shall be governed by and
               -------------
     construed in accordance with the laws of the State of Texas.

          10.5 Amendment.  This Agreement may be amended only by a written
               ---------
     instrument executed by the Company and Holders who hold a majority of the
     Registrable Securities.

          10.6 Termination.  This Agreement shall terminate and the
               -----------
     registration rights granted hereunder shall expire on the date that is two
     (2) years following the date on which the last Warrant is exercised or
     expires; provided that such termination and expiration shall not affect
     registration rights exercised prior to such date and the Company's
     obligation to indemnify any Holder under Section 7.

          10.7 Severability.  If any provision of this Agreement shall be
               ------------
     found by any court of competent jurisdiction to be invalid or
     unenforceable, such provision shall, to the maximum extent allowable by
     law, be modified by such court so that it becomes enforceable and, as
     modified, shall be enforced as any other provision hereof, all the other
     provisions hereof continuing in full force and effect.

                                      -12-
<PAGE>

          10.8  Headings.  The headings contained in this Agreement are for
                --------
     reference purposes only and shall not in any way affect the meaning or
     interpretation of this Agreement.

          10.9  Entire Agreement.  This Agreement and the Warrant Agreement
                ----------------
     constitutes the entire agreement of the parties with respect to the subject
     matter hereof and supersedes all prior and contemporaneous understandings,
     whether written or oral.

                  [Balance of Page Intentionally Left Blank]
                  ------------------------------------------

                                      -13-
<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first written above.

                                   COMPANY:

                                   RF Monolithics, Inc.


                                   By: /s/ David M. Kirk
                                       ----------------------------------
                                        Name: David M. Kirk
                                              ---------------------------
                                        Title: President
                                              ---------------------------

                                   HOLDER:

                                   Wells Fargo Business Credit, Inc.


                                   By:  /s/ Terrance O. McKinney
                                       ----------------------------------
                                        Name: Terrance O. McKinney
                                       ----------------------------------
                                        Title: Assistant Vice President
                                       ----------------------------------

                                      -14-