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                                                                   Exhibit 10.12


                              NONCOMPETE AGREEMENT
                                (Senior Employee)

         This NONCOMPETE AGREEMENT (the "Agreement"), made as of the 16 day of
November, 2000, is entered into between Hittite Microwave Corporation, a
Delaware corporation with offices at 12 Elizabeth Drive, Chelmsford, MA 01925
(the "Company"), and Yalcin Ayasli, an individual residing at 5 Ingleside Rd.,
Lexington, MA (the "Employee").

                                    Recitals:

         A.       The Employee is a key employee of the Company.

         B.       The Employee's execution of this Agreement is a condition to
the Company's grant of the foregoing securities to the Employee.

         NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

         1.       Non-Competition Covenants.

         (a)      Non-Competition Covenants. The Employee agrees that he will
not, during the Non-Competition Period (as hereinafter defined), directly or
indirectly:

                  (i)      as owner, employee, officer, director, partner,
         sales representative, agent, stockholder, capital investor, lessor,
         consultant or advisor, either alone or in association with others,
         (other than as a holder of not more than one percent of the outstanding
         shares of any series or class of securities of a company, which
         securities of such class or series are publicly traded in the
         securities markets), develop, design, produce, market, sell or render
         (or assist any other person or entity in developing, designing,
         producing, marketing, selling or rendering), products or services which
         are competitive with the Business of the Company (as hereinafter
         defined) anywhere in the world;

                  (ii)     solicit, divert or take away, or attempt to solicit,
         divert or take away, the business or patronage of any of the customers
         or referral sources of the Company with whom the Company has had a
         relationship during the period of the Employee's employment by the
         Company; or

                  (iii)    recruit, solicit or hire any employee of the Company,
         or induce or attempt to induce any employee of the Company to terminate
         his or her employment with, or otherwise cease his or her relationship
         with, the Company.

         (b)      Definitions. For the purposes of this Section 1, the following
terms shall have the respective meanings indicated below:

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                  (i)      "Non-Competition Period" shall mean the period during
         which the Employee is employed by the Company and the two-year period
         commencing on the last day of the Employee's employment by the Company,
         regardless of whether the Employee's termination was at the election of
         the Company, with or without cause, or at the election of the Employee,
         with or without good reason.

                  (ii)     "Business of the Company" shall mean the development,
         manufacture, marketing and/or distribution of monolithic microwave
         integrated circuits and assemblies for RF, microwave and millimeter
         wave applications or other products or services which the Company has
         under development or which are subject to active planning in a written
         document at the time the Employee is terminated.

         2.       Injunctive and Other Equitable Relief.

         (a)      The Employee consents and agrees that if he violates any of
the provisions of Section 1 hereof, the Company shall be entitled, in addition
to any other remedies it may have at law, to the remedies of injunction,
specific performance and other equitable relief for a breach by the Employee of
Section 1 of this Agreement. This Section 2(a) shall not, however, be construed
as a waiver of any of the rights which the Company may have for damages or
otherwise.

         (b)      Any waiver by the Company of a breach of any provision of
Section 1 hereof shall not operate or be construed as a waiver of any subsequent
breach of such provision or any other provision hereof.

         (c)      The Employee agrees that each provision of Section 1 shall be
treated as a separate and independent clause, and the unenforceability of any
one clause shall in no way impair the enforceability of the other clauses
herein. Moreover, if one or more of the provisions contained in Section 1 shall
for any reason be held to be excessively broad as to scope, activity or subject
so as to be unenforceable at law, such provision or provisions shall be
construed by the appropriate judicial body by limiting and reducing it or them
so as to be enforceable to the maximum extent compatible with the applicable law
as it shall then appear.

         3.       Other Agreements. The Employee represents and warrants that
his performance of all the terms of this Agreement and as an employee of the
Company does not and will not breach any other agreement by which he is bound.

         4.       Notices. All notices required or permitted under this
Agreement shall be in writing and shall be deemed effective upon personal
delivery or upon deposit in the United States Post Office, by registered or
certified mail, postage prepaid, addressed to the other party at the address
shown above, or at such other address or addresses as either party shall
designate to the other in accordance with this Section 4.

         5.       Not a Contract of Employment. Employee understands that this
Agreement does not constitute a contract of employment or give Employee rights
to employment or continued employment by the Company.

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         6.       Entire Agreement. This Agreement constitutes the entire
agreement between the parties and supersedes all prior agreements and
understandings, whether written or oral, relating to the subject matter of this
Agreement.

         7.       Amendment. This Agreement may be amended or modified only by a
written instrument executed by both the Company and the Employee.

         8.       Governing Law. This Agreement shall be construed, interpreted
and enforced in accordance with the laws of The Commonwealth of Massachusetts,
without regard to its choice of law principles. Employee hereby consents to (a)
service of process, and to be sued, in The Commonwealth of Massachusetts and (b)
to the jurisdiction of the courts of The Commonwealth of Massachusetts and the
United States District Court of Massachusetts, as well as to the jurisdiction of
all courts to which an appeal may be taken from such courts, for the purpose of
any suit, action or other proceeding arising out of any of Employee's
obligations hereunder, and Employee expressly waives any and all objections he
or she may have as to venue in any such courts.

         9.       Successors and Assigns. This Agreement shall be binding upon
and inure to the benefit of both parties and their respective successors and
assigns, including any corporation with which or into which the Company may be
merged or which may succeed to its assets or business, provided, however, that
the obligations of the Employee are personal and shall not be assigned by him.

         10.      Miscellaneous.

         (a)      No delay or omission by the Company in exercising any right
under this Agreement shall operate as a waiver of that or any other right. A
waiver or consent given by the Company on any one occasion shall be effective
only in that instance and shall not be construed as a bar or waiver of any right
on any other occasion.

         (b)      The captions of the sections of this Agreement are for
convenience of reference only and in no way define, limit or affect the scope or
substance of any section of this Agreement.

         (c)      This Agreement shall be interpreted in such a manner as to be
effective and valid under applicable law, but if any provision hereof shall be
prohibited or invalid under any such law, such provision shall be ineffective to
the extent of such prohibition or invalidity, without invalidating or nullifying
the remainder of such provision or any other provisions of this Agreement. If
any one or more of the provisions contained in this Agreement shall for any
reason be held to be excessively broad as to duration, geographical scope,
activity or subject, such provisions shall be construed by limiting and reducing
it so as to be enforceable to the maximum extent permitted by applicable law.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year set forth above.

                                            HITTITE MICROWAVE CORPORATION

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                                            By /s/ Yalcin Ayasli
                                               --------------------------------
                                               Yalcin Ayasli, President

                                            EMPLOYEE

                                            /s/ Yalcin Ayasli
                                            -----------------------------------
                                            Name: Yalcin Ayasli

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