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                                                                   Exhibit 10.10



                              ANALOG DEVICES, INC.
                               One Technology Way
                                 P. O. Box 9106
                        Norwood, Massachusetts 02062-9106



                                          May 18, 1994

Metropolitan Life Insurance Company
One Madison Avenue
New York, New York 10010

Attention:  Treasurer

            Re:  8.87% Senior Secured Notes Due May 1, 2007
                 ------------------------------------------

Gentlemen:

          Capitalized terms used herein but not otherwise defined shall have
the meanings specified in the Note Agreement, as hereinafter defined.

          In connection with the $10,500,000 loan (the "Loan") made by
Metropolitan Life Insurance Company (together its with successors and assigns,
"Metropolitan") to Francis J. Perry, Jr. and William J. Walker, not in their
individual capacities but solely as Trustees of Everett Street Trust under
Declaration of Trust, dated May 9, 1980 (the "Borrower"), pursuant to and as
described in the Note Purchase Agreement, dated May 18, 1994, between
Metropolitan and the Borrower (the "Note Agreement") and the Notes evidencing
the Loan executed by the Borrower to Metropolitan or its registered assigns
(the "Notes"), Analog Devices, Inc. (the "Company") agrees with Metropolitan
as follows:

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                                    ARTICLE I

                             OBLIGATION TO PURCHASE


          1.1 PURCHASE. (a) Upon the occurrence and during the continuance of
(i) an "Event of Default", as defined in the Mortgage, Security Agreement and
Fixture Filing, dated as of May 1, 1994 (the "Mortgage"), from the Borrower, as
mortgagor, to Metropolitan, as mortgagee, or (ii) an "Event of Default", as
defined in the Guaranty, dated as of May 1, 1994 (the "Guaranty"), from the
Company to Metropolitan or (b) at such time when all principal payable under the
Notes has become or has been declared due and payable, whether upon the stated
maturity of the Notes of May 1, 2007 or otherwise, or (c) at any time if the
Lease (as defined in the Notes) is terminated by either the Borrower or the
Company prior to May 1, 2007, or (d) at any time if the Fixed Rent (as defined
in the Lease) payable under the Lease is reduced or suspended so that the Debt
Service Portion of Fixed Rent (as defined in the Lease) is not sufficient to pay
in full the Installment Payments (as defined in the Notes) then due under the
Notes or (e) upon the determination by Metropolitan of the existence of a
Material Environmental Condition (as hereinafter defined) with respect to the
Property, the Company will, upon written demand by Metropolitan, and at the
time, in the manner and otherwise as hereinafter set forth, purchase and pay for
the Notes. The purchase shall be made within 15 days after such demand is made,
for an amount (the "Purchase Price") payable in immediately available funds
equal to the aggregate outstanding principal amount of the Notes, together with
all accrued and unpaid interest thereon and all other costs, fees and charges
due and payable under or with respect to the Guaranty and the Mortgage,
including, without limitation, the Make-Whole Payment (as defined in the
Mortgage), if any. Notwithstanding the foregoing, Metropolitan and the Company
agree that the Purchase Price payable hereunder (x) upon the termination of the
Lease

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pursuant to Section 7.1 of the Lease solely on account of a casualty in the
final 3 years of the term of the Lease or (y) upon the termination of the Lease
pursuant to Section 7.2 of the Lease solely on account of a taking of the
Property at any time or (z) upon a purchase contemplated by subparagraph (e)
above, shall not include the Make-Whole Payment. Upon any purchase, Metropolitan
shall, without representation or warranty, express or implied, other than as to
the ownership by Metropolitan of the Notes free and clear of any encumbrances
created by or through Metropolitan, and without recourse on the part of
Metropolitan, endorse and deliver the Notes and assign the Note Agreement and
any related documents to the Company.

          As a condition of Metropolitan's making the Loan, Metropolitan has
required the Company to complete an Environmental Due Diligence Questionnaire
(the "Questionnaire") with respect to the Property. The Company agrees that if
upon completion and delivery to Metropolitan of the Questionnaire, together with
any supplements thereto as may be required by Metropolitan, Metropolitan in good
faith determines that further environmental testing, monitoring, investigation
or other review of the Property is warranted, then the Company shall, at its
sole cost and expense, engage a firm of independent qualified environmental
engineers acceptable to Metropolitan (the "Independent Engineers") to conduct
such testing, monitoring, investigation and review, including, without
limitation, preparation of a "Phase I" environmental site assessment (the "Phase
I ESA"). If, based upon review of the Phase I ESA or such other tests, reports,
evaluations or reviews as are prepared by the Independent Engineers,
Metropolitan determines in good faith that additional testing of the Property is
warranted, the Company agrees to provide for such additional testing, at its
sole cost and expense, by a firm of Independent Engineers.

          Upon the conclusion of all environmental testing, investigation and
review with respect to the Property which Metropolitan has required as

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permitted above, Metropolitan shall inform the Company in writing of whether
Metropolitan believes that a "Material Environmental Condition" exists with
respect to the Property. A "Material Environmental Condition" shall exist if
Metropolitan in good faith determines, based on its review of the Questionnaire,
any supplement thereto, any Phase I ESA and/or any other report prepared in
connection with the Property, that an environmental condition exists with
respect to the Property that could materially adversely affect Metropolitan's
investment in the Notes or the Property as collateral therefor or could
materially adversely affect the Company's business, prospects or financial
condition.

          Upon receipt of written notice from Metropolitan that a Material
Environmental Condition exists, the Company will purchase and pay for the Notes
in accordance with the terms of this Agreement.

          1.2 TAXES, AUTHORIZATIONS, ETC. The Company will pay any stamp, with
respect to the purchase of the Notes pursuant to this Agreement other than any
gross receipts or net income or similar tax of Mortgagee payable with respect to
such purchase. If any such tax is paid by Metropolitan, the Company will, upon
demand of Metropolitan and whether or not such tax will be correctly or legally
asserted, promptly pay to Metropolitan all such amounts incurred by Metropolitan
for such payment, together with any interest, penalties and expenses in
connection therewith. The Company hereby indemnifies and holds harmless
Metropolitan for such payment, together with all such interest, penalties and
expenses incurred in connection therewith, in the event of the failure of the
Company to pay such stamp or other tax as hereinabove set forth. The provisions
of this Section 1.2 shall survive the purchase of the Notes contemplated herein.

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          The Company will obtain any authorization or approval or other action
by, and will give any notice to or make any filing with, any governmental
authority or regulatory body required in connection with the transfer of the
Notes and related documents to the Company upon any purchase pursuant to this
Agreement. Nothing in this paragraph shall obligate the Company to obtain any
such authorization or approval or other action by, or give any such notice to or
make any such filing if any such authorization, approval, action, notice, or
filing is required solely by or with respect to Metropolitan.

          1.3 OBLIGATION ABSOLUTE. The Company acknowledges and agrees that the
obligations of the Company as set forth in this Agreement are material
inducements to Metropolitan in purchasing the Notes from the Borrower. The
Company hereby agrees that its obligations under this Agreement are absolute and
unconditional, independent of the ability of the Borrower to perform any of its
obligations to Metropolitan or to the Company or the performance by any person
or entity of his or its respective obligations, and without regard to any law,
regulation or order now or hereafter in effect in any jurisdiction affecting the
Notes or any of the terms of the Note Agreement, the Notes, the Mortgage, the
Lease, the Guaranty or any other document related thereto or the rights of
Metropolitan with respect thereto, and irrespective of the following:

          (a) Any lack of genuineness, legality, validity, enforceability or
value of the Note Agreement or Notes or any other agreement or instrument
relating thereto or any collateral therefor;

          (b) Any change in the time, manner or place of payment of any
obligations under the Notes, or any term of the Note Agreement, the Mortgage or
the Notes or any amendment or waiver of or any consent to departure from

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the terms of the Note Agreement, the Mortgage or the Notes or any other related
documents;

          (c) Any exchange, release or non-perfection of any collateral
including, without limitation, the Mortgaged Property (as defined in the
Mortgage);

          (d) Any failure to pay any taxes which may be payable with respect to
the issuance or transfer of any Note and related documents; or any failure to
obtain any authorization or approval from, or other action by, or to notify or
file with, any governmental authority or regulatory body required in connection
with the issuance or transfer of any Note and related documents;

          (e) Any impossibility or impracticality of performance, FORCE MAJEURE,
OR any act of any government, or any other circumstance which might constitute a
defense available to, or a discharge of, the Borrower in respect of the
obligations under the Note Agreement, the Mortgage or the Notes or any party
obligated thereunder or any circumstance, event or happening whatsoever, whether
foreseen or unforeseen and whether similar or dissimilar to anything referred to
in this Section 1.3(e), which in any manner would constitute a legal, equitable
or other excuse for non-performance by the Borrower or the Company;

          (f) The validity of the organization of the Borrower or the Company or
any other entity, the termination of existence of the Borrower, the Company or
any person or entity or the receipt or non-receipt of any approvals, directions
or consents or other authorizations to act on behalf of the Company or the
Borrower;

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          (g) Any defense, claim, setoff, recoupment, abatement or other right,
existing or future, which the Company may have against the Borrower or any other
person or entity;

          (h) The inaccuracy of any representation, warranty or statement made
by or on behalf of any person or entity in connection with the issuance of the
Notes (other than those representations, warranties and statements contained in
Sections 7.1 and 7.2 of the Note Agreement);

          (i) The bankruptcy, insolvency, reorganization, liquidation,
dissolution, winding up, arrangement, composition, readjustment of debt or
similar event with respect to the Borrower or the Company or any other person or
entity.

          This Agreement shall continue to be effective or be reinstated, as the
case may be, if at any time any payment under or with respect to any Note is
rescinded or must otherwise be returned by Metropolitan upon the insolvency,
bankruptcy or reorganization of the Borrower or otherwise, all as though such
payment had not been made. The obligations of the Company under this Agreement
shall not be subject to reduction, termination or other impairment by reason of
any setoff, recoupment, counterclaim or defense or for any other reason.

          1.4 WAIVER. The Company hereby waives promptness, diligence and notice
of acceptance with respect to the Note Agreement, the Mortgage and the Notes,
and any requirement that Metropolitan protect, secure, perfect or insure any
security interest in or lien on any property including, without limitation, the
Mortgaged Property, which may become subject thereto or exhaust any right or
take any action against the Borrower, or any other person or entity or any
collateral including, without limitation, the Mortgaged Property and the
Guaranty.

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          1.5 SUBROGATION. Until all sums owing hereunder have been paid in full
to Metropolitan, any rights of subrogation or other rights or remedies which the
Company might have against the Borrower as a result of any payments made
hereunder or otherwise in connection with its undertaking under this Agreement
shall be subordinate to the rights of Metropolitan under the Notes, Note
Agreement, the Mortgage and other related documents and the Company shall not
exercise any such rights and remedies without the consent of Metropolitan.


                                   ARTICLE II

                                    REMEDIES

          2.1 FAILURE TO PURCHASE. If the Company shall fail to pay the Purchase
Price for the Notes within the time period and in the manner set forth above,
the Company (i) agrees that it will be unconditionally liable to Metropolitan
for liquidated damages (for the loss of a bargain and not as a penalty) for the
amount of such Purchase Price as well as for all costs and expenses, if any,
incurred by Metropolitan in enforcing this Agreement, and (ii) irrevocably
waives to the full extent permitted by applicable law any right or defense the
Company may have to cause Metropolitan to prove the cause or amount of such
damages or to mitigate the same.

          2.2 ADDITIONAL REMEDIES. The Company agrees that Metropolitan may
bring hereunder and prosecute against the Company a separate action or actions
whether or not the Company brings an action against the Borrower and whether or
not the Borrower is joined in any such action or actions. Metropolitan shall
have, in its sole discretion and without limitation of any other remedies of
Metropolitan with respect to this Agreement and the performance obligations
called for hereby, a right of specific performance of the obligations of the
Company under this Agreement, including but not limited

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to the obligation to purchase the Notes for the Purchase Price, and the right to
commence suit for compensatory, consequential and liquidated damages.

          2.3 INDEMNIFICATION. The Company agrees to indemnify and defend
Metropolitan against and hold Metropolitan harmless from all liabilities,
damages, costs and expenses (including, without limitation, reasonable
attorneys' fees), sustained or incurred (a) as a result of the failure of the
Company to comply with its obligations hereunder or (b) in connection with
Metropolitan's purchase of the Notes from the Borrower or enforcement of any of
its rights with respect thereto.


                                   ARTICLE III

                                  Miscellaneous

          Section 3.1 GENERAL PROVISIONS. This Agreement cannot be changed,
discharged or terminated orally, but only by an instrument in writing signed by
the party against which enforcement of the same is sought; PROVIDED, HOWEVER,
that the terms of Section 1.1 of this Agreement may not be amended in any manner
which would materially and adversely affect the Borrower's interests and rights
with respect to the Property without the consent of the Borrower, which consent
shall not be unreasonably withheld or delayed. All the terms of this Agreement
shall be binding upon, inure to the benefit of and be enforceable by the
respective successors and assigns of the parties hereto, and, in particular,
shall inure to the benefit of and be enforceable by any registered owner or
holder of any of the Notes. The headings to the various sections of this
Agreement have been inserted for the convenience of reference only and shall not
limit or otherwise affect any of the terms hereof. This Agreement may be
executed in any number of counterparts, each of which shall be an original, but
all of which together shall constitute one and the same

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instrument. This Agreement shall be construed and enforced in accordance with,
and governed by, the laws of the Commonwealth of Massachusetts.

          Section 3.2 CONSENT TO JURISDICTION. The Company hereby irrevocably
and unconditionally submits, for itself and its property, to the non-exclusive
jurisdiction of any New York state court or federal court of the United States
of America sitting in New York, and any appellate court from any thereof, in any
action or proceeding arising out of or relating to this Agreement, or for
recognition and enforcement of any judgment, and irrevocably and unconditionally
consents to all claims in respect of any such action or proceeding being heard
and determined in such New York state court or, to the extent permitted by law,
in such Federal court. A final judgment in any such action or proceeding shall
be conclusive and may be enforced in other jurisdictions by suit on the judgment
or in any manner provided by law. Nothing in this Agreement shall affect any
right that any party may otherwise have to bring any action or proceeding
relating to this Agreement against the Company or its properties in the courts
of any jurisdiction.

     The Company hereby irrevocably and unconditionally waives, to the fullest
extent it may legally and effectively do so, any objection which it may now or
hereafter have to the laying of venue of any suit, action or proceeding arising
out of or relating to this Agreement in any New York state or Federal court. The
Company hereby irrevocably waives, to the fullest extent permitted by law, the
defense of an inconvenient forum to the maintenance of such action or proceeding
in any such court.

     The Company irrevocably consents to service of process in the manner
provided for notices in Section 13 of the Guaranty. Nothing in this Agreement
will affect the right of any party to serve process in any other manner
permitted by law.

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     If you are in agreement with the foregoing, please sign the enclosed
counterparts and return one to the Company whereupon this Agreement shall become
a binding contract under seal between you and the Company.

                                   Very truly yours,

                                   ANALOG DEVICES, INC.



                                   By: /s/ William A. Martin
                                       -----------------------
                                       Name: William A. Martin
                                       Title: Treasurer


The foregoing Agreement is
hereby agreed to as of the
date first above written.

METROPOLITAN LIFE INSURANCE COMPANY

By: /s/ Francis M. Donnantuono
    ----------------------------
    Name: Francis M. Donnantuono
    Title:

By: /s/ Richard G. Clarke
    ----------------------------
    Name: Richard G. Clarke
    Title: