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                                                                    Exhibit 10.8

           SECOND AMENDMENT TO EQUIPMENT AND COMMERCIAL REVOLVING LINE
               CREDIT AGREEMENT AND RATIFICATION OF LOAN DOCUMENTS

         This Second Amendment to Equipment and Commercial Revolving Line of
Credit Agreement and Ratification of Loan Documents (the "SECOND AMENDMENT") is
dated as of July 7, 2004 by and between CITIZENS BANK OF MASSACHUSETTS (the
"BANK"), a Massachusetts bank with a principal place of business at 28 State
Street, Boston, Massachusetts 02109, and HITTITE MICROWAVE CORPORATION (the
"BORROWER") a Delaware corporation with a principal place of business at 12
Elizabeth Drive, Chelmsford, Massachusetts 01824.

         WHEREAS, the Bank extended to the Borrower a revolving line of credit
facility in the amount of Four Million ($4,000,000.00) Dollars (the "REVOLVING
CREDIT") and an equipment line of credit facility in the amount of Four Million
($4,000,000.00) Dollars (the "EQUIPMENT CREDIT") as set forth in an Equipment
and Commercial Revolving Line of Credit Agreement dated September 30, 2001 (the
"ORIGINAL CREDIT AGREEMENT" and together with all modifications and amendments
the "CREDIT AGREEMENT");

         WHEREAS, the Borrower and the Bank entered into a Modification
Agreement dated June 7, 2002 extending the Conversion Date of the Equipment
Credit from May 31, 2002 to July 31, 2002, and a subsequent Modification
Agreement dated August 21, 2002 whereby the availability of Loans under the
Equipment Credit was reduced to Two Million ($2,000,000.00) Dollars and the
Conversion Date was extended to May 31, 2003;

         WHEREAS, pursuant to a First Amendment to Equipment and Commercial
Revolving Line Credit Agreement and Ratification of Loan Documents, the Borrower
and the Bank: (a) extended the Termination Date of the Revolving Credit from May
31, 2003 to May 31, 2005; (b) extended the Conversion Date of the Equipment
Credit from July 31, 2002 to May 31, 2004; (c) amended the interest rate options
under the Equipment Credit to a rate per annum after the Conversion Date, at the
election of the Borrower, of either (1) the Prime Rate; or (2) the LIBOR Lending
Rate for one month Interest Periods plus two hundred (200) basis points, (d)
reduced the maximum amount of purchase money financing permitted to One Million
($1,000,000.00) Dollars; and (e) increased the minimum Tangible Net Worth
covenant so as to require minimum Tangible Net Worth of Twenty Million
($20,000,000.00) Dollars;

         WHEREAS, subject to the terms and conditions of this Second Amendment,
the Borrower and the Bank have agreed to: (a) extend the Termination Date of the
Revolving Credit to from May 31, 2005 to May 31, 2006; (b) extend the Conversion
Date of the Equipment Credit from May 31, 2004 to May 31, 2005; and (c) amend
the minimum Tangible Net Worth covenant so as to require a minimum Tangible Net
Worth of Twenty-Five Million. ($25,000,000.00) Dollars;

         NOW THEREFORE, in consideration of good and valuable consideration, the
receipt of which is hereby acknowledged, the parties hereby agree as follows:

         1.       The Credit Agreement is hereby amended as follows:

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                  (a)      The definition of Termination Date in Section 1.01 of
the Credit Agreement is hereby amended to substitute the date "May 31, 2006" in
lieu of "May 31, 2005", thereby extending the Termination Date to May 31, 2006;

                  (b)      Section 2.012 of the Credit Agreement is hereby
amended by extending the Conversion Date of the Equipment Credit to May 31,
2005. Advances which are termed out under the Equipment Credit shall be
evidenced by one or more separate commercial promissory notes, each in a form
substantially identical to Exhibit A-1 annexed to the First Amendment. The
parties hereby confirm that the Equipment Credit has previously been amended so
that the aggregate of all Loans under the Equipment Credit shall not exceed Two
Million ($2,000,000.00) Dollars at any time.

                  (c)      Section 7.02 of the Credit Agreement is hereby
amended by substituting the language, "Twenty-Five Million ($25,000,000.00)
Dollars" in lieu of the language, "Twenty Million ($20,000,000.00) Dollars", so
as to impose the requirement that the Borrower shall, at all times, maintain a
minimum Tangible Net Worth of not less than Twenty-Five Million ($25,000,000.00)
Dollars, which covenant will continue to be monitored quarterly.

         2.       Simultaneously herewith, the Borrower shall deliver to the
Bank the following documents:

                  (a)      A Second Allonge to and Amendment of Revolving Credit
Note;

                  (b)      A Second Allonge to and Amendment of Master Equipment
Promissory Note;

                  (c)      A Secretary's Certificate attesting to the authority
of the person executing this Second Amendment and the other documents
contemplated hereby, including the above referenced Amendments and Allonges; and

                  (d)      An updated insurance certificate on ACORD Form No. 27
concerning property and casualty insurance naming the Bank as the loss payee;
and

                  (e)      Such other documents and instruments as the Bank
shall reasonably require.

         3.       Except as expressly set forth herein, the Borrower hereby
acknowledges and agrees that the Original Credit Agreement, as previously
amended, remains unmodified and in full force and effect. Further, the Borrower
hereby acknowledges and agrees that the other loan documents heretofore executed
and delivered by the Borrower, evidencing the Obligations, including, without
limitation, the Master Equipment Promissory Note dated September 30, 2001 in the
original principal amount of Four Million ($4,000,000.00) Dollars, as previously
amended by a Modification Agreement dated August 21, 2002, as further amended by
an Allonge to and Amendment of Master Equipment Promissory Note dated June 25,
2003, the Revolving Credit Note dated September 30, 2001 in the original
principal amount of Four Million ($4,000,000.00) Dollars, as further amended by
an Allonge to and Amendment of Revolving Credit Note dated June 25, 2003, the
Security Agreement executed and delivered by the Borrower (the "SECURITY
AGREEMENT") dated as of September 30, 2001, and all other related documents and
instruments

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executed and delivered by Borrower, and all extensions and modifications thereof
and amendments and supplements thereto and all UCC financing statements
(collectively the "LOAN DOCUMENTS") remain in full force and effect, and the
Borrower hereby ratifies and confirms that all Obligations of the Borrower to
the Bank, whether now existing or hereafter arising, remain secured by a first
lien on all assets of the Borrower granted pursuant to the Security Agreement.

         4.       The Borrower represents and warrants that:

                  (a)      the representations and warranties contained in
Credit Agreement and in the Security Agreement remain true and accurate in all
material respects;

                  (b)      no Default or Event of Default has occurred and is
continuing, or will result from this Second Amendment, and no event has occurred
which with the giving of notice and or the lapse of time; or both, would
constitute a Default or Event of Default under the Credit Agreement or any of
the other Loan Documents; and

                  (c)      there has been no material adverse change in the
assets, liabilities, financial condition or business of the Borrower, since the
date of the Financial Statements most recently given by the Borrower.

         5.       The Borrower represents and warrants to the Bank, and agrees,
that the Borrower has no defenses, set-offs or counterclaims to the payment of
its liabilities and obligations to the Bank under the Loan Documents. To the
extent any such defenses, set-offs or counterclaims ever existed, Borrower
hereby waives them, and the Borrower hereby releases, remises and forever
discharges the Bank, its agents, directors, officers, employees and attorneys,
of and from and all claims now existing of the Borrower, against the Bank, its
agents, directors, officers, employees and attorneys.

         6.       The Borrower agrees, warrants, represents and certifies to the
Bank that the obligations and liabilities of the Borrower arising out of and/or
under the Loan Documents are the legal, valid, binding obligations of the
Borrower, where applicable, and the Borrower hereby ratifies, reaffirms,
confirms, and agrees to be bound to the Bank for its obligations under the Loan
Documents, as amended herein and/or hereafter.

         7.       The Borrower agrees and warrants, ratifies, confirms and
reaffirms to the Bank that all liens, encumbrances and security interests, under
the Loan Documents granted to the Bank, including, without limitation, the
Security Agreement and the liens granted pursuant thereto, continue to remain
valid, perfected and enforceable by the Bank, without the necessity of any
further action or recording, and secure all obligations arising under the Credit
Agreement, including without limitation, the Revolving Credit and the Equipment
Credit;

         8.       Except as otherwise prohibited by law, if at all, the Borrower
agrees that any and all now existing and/or hereafter arising deposits, or other
sums, certificates, instruments and/or securities at any time credited by, or
due to, the Borrower from the Bank, now existing and/or hereafter arising (all
the foregoing collectively called "DEPOSITS") shall, at all times, constitute
security for all the obligations of the Borrower, and/or any and all other
liabilities, now existing and/or hereafter arising of the Borrower to the Bank,
and, after any Event of Default or default,

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may be held, applied and/or set off by the Bank, against the liabilities at any
time of the Borrower, whether or not other collateral is held by otherwise
available to the Bank.

         9.       The Borrower acknowledges that: (a) the Bank has made no
agreements, warranties, representations or promises in connection with this
Agreement except as set forth herein, and (b) Borrower have received from the
Bank good and adequate consideration in connection with the execution of this
Agreement; and (c) the responsibility of the attorney for the Bank is to protect
the interest of the Bank; and the Borrower may, at Borrower's own expense,
engage one or more attorneys of their own selection to represent the Borrower.

         10.      This Agreement may be executed in any number of counterparts,
and when each party has signed and delivered at least one such counterpart, each
counterpart shall be considered an original, and when taken together with other
signed counterparts, shall constitute one agreement, which shall be binding upon
and effective as to all parties. This Agreement and the rights and obligations
hereunder may not be modified, amended or waived, whether in whole or in part,
orally or otherwise, except by written instrument signed by the Bank, its
successors or assigns. This Agreement is binding upon and shall inure to the
benefit of the parties hereto, their heirs, executors, administrators,
successors and assigns. This Agreement shall be deemed to have been executed and
delivered within the Commonwealth of Massachusetts, and the rights and
obligations of the parties hereto shall be construed and enforced in accordance
with, and governed by, the laws of the Commonwealth of Massachusetts. Each party
has cooperated in the drafting and preparation of this Agreement; hence, in any
construction to be made of this Agreement, the same shall not be construed
against any party.

         11.      The Borrower agrees to execute, acknowledge and deliver such
further instruments and perform such additional acts as the Bank shall
reasonably require in order to effectuate the intent of this Agreement. The
Borrower shall be responsible to pay any and all costs and expenses reasonably
incurred by the Bank in connection with this Second Amendment, including,
without limitation, all reasonable attorneys fees, and hereby authorizes the
Bank to charge the Borrower's account for reimbursement of the same.

         12.      Except as otherwise set forth herein, capitalized terms shall
have the meaning ascribed to them in the Original Credit Agreement, as amended.
All references to the Bank shall mean Citizens Bank of Massachusetts, as
successor by merger to USTrust, and all references to the Prime Rate or the Base
Rate shall mean the Citizens Bank of Massachusetts Base Rate, as announced by
the Bank from time to time, said rate to automatically change effective on the
date of an announcement of a change in the Base Rate.

         13.      This Second Amendment, together with the Original Credit
Agreement, as previously amended, and the other Loan Documents contain the
entire agreements between the parties concerning the subject matter of said
agreements and supersede all prior understandings, may be modified or amended
only by written agreement and shall be binding upon and inure to the benefit of
the parties hereto and their successors and assigns.

                            [Signature Page Follows]

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         IN WITNESS WHEREOF, the parties have executed or caused this agreement
to be executed by their respective officers hereunto duly authorized, as of the
day first written above and it and shall take effect as a sealed instrument.

                              HITITTE MICROWAVE CORPORATION


                              By: /s/ Yalcin Ayasi
                                  --------------------------------------------
                              Yalcin Ayasli, Chairman, Chief Executive Officer


                              CITIZENS BANK OF MASSACHUSETTS


                              By:
                                  ---------------------------------------
                              Christopher J. Wickles, Vice President


                        THE COMMONWEALTH OF MASSACHUSETTS

Middlesex, ss

         On this 7th day of July, 2004, before me, the undersigned notary
public, personally appeared the above named Yalcin Ayasli, Chairman, Chief
Executive Officer of Hittite Microwave Corporation, proved to me through
satisfactory evidence of identification, which was a Massachusetts driver's
license, to be the person whose name is signed on the preceding or attached
document, and acknowledged to me that he signed it voluntarily for its stated
purpose in his capacity as President of Hittite Microwave Corporation.


                                      /s/ William Sylvanowicz
                                      ------------------------------------------
                                      Notary Public
                                      My commission expires:  January 23, 2009

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