UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 10/A

                                 Amendment No. 1

                        GENERAL FORM FOR REGISTRATION OF SECURITIES
     Pursuant to Section 12(b) or (g) of The Securities Exchange Act of 1934

                              MICROSEMI CORPORATION
                              ---------------------
             (Exact name of registrant as specified in its charter)



       Delaware                                                   95-2110371
--------------------------------                        -----------------------------------
                                                     
(State or other jurisdiction of incorporation or        (I.R.S. Employer Identification No.)
 organization)

 2381 Morse Ave., Irvine, California                    92614
-----------------------------------------------         -----------------------------------
(Address of principal executive offices)                (Zip Code)

Registrant's telephone number, including area code  (949) 221-7100
                                                   ----------------------------------------

Securities to be registered pursuant to Section 12(b) of the Act:

Title of each class                                     Name of each exchange on which
to be so registered                                     each class is to be registered
None                                                    Not Applicable
--------------------------------                        -----------------------------------

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

Securities to be registered pursuant to Section 12(g) of the Act:
 Common Stock, par value $.20 per share
-------------------------------------------------------------------------------------------
                                (Title of class)

 Preferred Stock, par value $1.00 per share
-------------------------------------------------------------------------------------------
                                (Title of class)




                 INFORMATION REQUIRED IN REGISTRATION STATEMENT

Item       Description of Registrant's Securities to be Registered.
11.
           The Company originally registered the Common Stock and the Preferred
           Stock under Section 12(g) of the Securities Exchange Act of 1934 on a
           Form 10 filed March 16, 1979. The Board of Directors has designated a
           series of Preferred Stock known as the Series A Junior Participating
           Preferred Stock. That series is registered under Section 12(g) of the
           Securities Exchange Act of 1934 on a Form 8-A filed December 29,
           2000. The registration thereof is not amended or superseded by this
           Form 10/A. The description of capital stock being registered that was
           reported in Item 12 of the Company's Form 10 filed March 16, 1979 is
           amended and restated in its entirety as follows:

           We are authorized to issue 100,000,000 shares of Common Stock, $.20
           par value per share (the "Common Stock"). As of January 14, 2002,
           28,505,107 shares of Common Stock were issued and outstanding.
           Additional shares of authorized and unissued Common Stock are
           committed or reserved for future issuances.

           We are authorized to issue 1,000,000 shares of Preferred Stock, $1.00
           par value per share (the "Preferred Stock"). As of February 7, 2002,
           no shares of Preferred Stock were issued or outstanding.

           Common Stock
           ------------
           Each stockholder is entitled to one vote for each share of Common
           Stock held of record on all matters to be voted on by stockholders,
           and stockholders are not entitled to cumulate votes for the election
           of directors. Stockholders have no preemptive rights or other
           subscription rights. There are no conversion rights or redemption
           rights with respect to shares of Common Stock. All outstanding shares
           of Common Stock are validly issued, fully paid and nonassessable.
           Holders of Common Stock are entitled to such dividends as may be
           declared by the Board of Directors out of funds legally available
           therefor. On our liquidation, dissolution or winding up, the holders
           of Common Stock are entitled to receive pro rata our net assets
           remaining after the payment of debts, expenses and the liquidation
           preference of any outstanding shares of Preferred Stock. The Board of
           Directors can issue or reserve additional Common Stock without the
           approval of stockholders, subject to stockholder approval
           requirements that may apply in some exceptional circumstances from
           time to time. The Company can issue Common Stock at prices and for
           considerations that the Board of Directors approves. The Common Stock
           is presently quoted on the Nasdaq National Market under the symbol
           "MSCC."

           Registration Rights
           -------------------
           In June 1992, we granted registration rights with respect to shares
           of our common stock that were issuable upon conversion of convertible
           subordinated promissory notes. We filed a registration statement on
           Form S-3 in order to register the resale of those shares.

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           Through the present we have maintained the effectiveness of the Form
           S-3 registration. We estimate that 325,000 shares of common stock
           remain unsold under the Form S-3.

           Transfer Agent and Registrar
           ----------------------------
           The transfer agent and registrar for our Common Stock is ChaseMellon
           Shareholder Services, 400 South Hope Street, 4th Floor, Los Angeles,
           California 90071, Attention: Stock Transfer Administration.

           Preferred Stock
           ---------------
           Our Board of Directors, pursuant to the Certificate of Incorporation,
           is authorized to issue up to 1,000,000 shares of Preferred Stock in
           one or more series and to fix the voting rights, liquidation
           preferences, dividend rights, conversion rights, redemption rights
           and terms, including sinking fund provisions, and certain other
           rights and preferences of the Preferred Stock. The Board of
           Directors, without stockholder approval, can therefore, issue
           Preferred Stock with voting, conversion and other rights that could
           adversely affect the voting power and other rights of, and amounts
           payable with respect to, the Common Stock. This may be deemed to have
           a potential anti-takeover effect because the issuance of Preferred
           Stock in accordance with such provision may delay, defer or prevent a
           change of control regarding us and could adversely affect the price
           of our Common Stock.

           Delaware Law
           ------------
           We are subject to the provisions of Section 203 of the Delaware
           General Corporation Law. In general, Section 203 prohibits a publicly
           held Delaware corporation from engaging in a "business combination"
           with an "interested stockholder" for a period of three years after
           the date of the transaction in which the person became an interested
           stockholder, unless either (i) prior to the date on which the person
           becomes an interested stockholder, the Board of Directors approves
           such transaction or business combination, (ii) the stockholder
           acquires more than 85% of the outstanding voting stock of the
           corporation (excluding shares held by directors who are officers or
           held in certain employee stock plans) upon consummation of such
           transaction, or (iii) the business combination is approved by the
           Board of Directors and by two- thirds of the outstanding voting stock
           of the corporation (excluding shares held by the interested
           stockholder) at a meeting of stockholders (and not by written
           consent). A "business combination" includes a merger, asset sale or
           other transaction resulting in a financial benefit to such interested
           stockholder. For purposes of Section 203, "interested stockholder" is
           a person who, together with affiliates and associates, owns (or
           within three years prior, did own) 15% or more of the corporation's
           voting stock.

           Shareholder Rights Plan
           -----------------------
                    Each outstanding shares of Common Stock includes, subject to
           adjustment and redemption, one Right to purchase one one-thousandth
           of a share of Series A Junior Participating Preferred Stock. Under
           certain circumstances, the rights entitle the holders

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           to acquire shares of Common Stock of the Company or a successor
           company at a discounted price. Such rights become null and void as to
           Common Stock held or transferred by any person that, together with
           its affiliates, acquires 20% or more of the outstanding Common Stock
           or makes an offer to purchase Common Stock and would thereby acquire
           aggregate ownership 30% or more of the outstanding Common Stock,
           unless the Board of Directors of the Company approves the
           transaction. Therefore, as to such an acquiring person, such rights
           are dilutive. The Rights will not trade separately from the Common
           Stock unless and until certain events occur. The Shareholder Rights
           Plan has a potential anti-takeover effect because the triggering of
           the rights in accordance with the Rights Agreement may delay, defer
           or prevent a change of control regarding us and could adversely
           affect the price of our Common Stock.

           Executive Change of Control Agreements
           --------------------------------------
           The Company has entered into agreements with Messrs. James J.
           Peterson and David R. Sonksen intended to assure their unbiased
           counsel and continued dedication in the event of an unsolicited
           tender offer or other occurrence that may result in a change of
           control. Each agreement will continue in effect until two (2) years
           after the Company notifies the executive of an intention to terminate
           that agreement. The terms of each agreement provide that, in the
           event of a change of control, as defined therein, and the subsequent
           termination of the executive's employment at any time during the term
           of such agreement, the executive will be paid amounts equal to a
           multiplier (the "Multiplier") times the sum of his annual salary rate
           in effect prior to termination of employment and his highest annual
           bonus paid during the prior 3-year period. The Multiplier is a number
           equal to the sum of three plus the number of years of service of the
           executive, all divided by twelve; provided, however, in the event of
           involuntary termination by the Company or termination by the
           executive for "Good Reason", the Multiplier will be equal to two (2).
           Provided, further, that in all other events the multiplier shall be
           at least one (1) and not more than one and one-half (1 1/2).
           Presently Mr. Peterson has 3 years of service and Mr. Sonksen has 15
           years of service. Additionally: (i) all options that the executive
           has received under any option plans will remain exercisable for a
           number of years equal to the Multiplier; (ii) medical, dental, vision
           and life insurance premiums will continue to be paid by the Company
           for a number of years equal to the Multiplier; (iii) his automobile
           allowance continues, subject to earlier termination if the executive
           becomes a full time employee elsewhere, up to a number of years equal
           to the Multiplier; and (iv) he will receive all other benefits then
           accrued at the time of a termination under the Company's compensation
           plans. Upon an involuntary termination or a termination for "Good
           Reason," in either case only following a change of control, all of
           the executive's unvested stock options, or similar equity incentives,
           vest and become exercisable. Also, to the extent that payments to the
           executive pursuant to his agreement (together with any other payments
           or benefits) would result in the triggering of the provisions of
           Sections 280G and 4999 of the Internal Revenue Code ("Code"), the
           agreement provides for the payment of an additional

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           amount such that the executive would receive, net of excise taxes,
           the amount he would have been entitled to receive in the absence of
           the excise tax provided in Section 4999 of the Code. Mr. Sonksen's
           current agreement restates and supersedes the similar agreement
           entered into in 1997. These agreements have a potential anti-takeover
           effect because if a change of control occurs, the Company may incur
           the additional costs described above, which could adversely affect
           the price an acquiror would be willing to pay for our Common Stock.



Item 15.   Financial Statements and Exhibits.

           (a)  None.

           (b)  3     Bylaws of the Registrant* (1)
                3.1   Amended and Restated Certificate of Incorporation of the
                      Registrant effective August 9, 2001* (2)
                4.2   Rights Agreement dated December 22, 2000 between the
                      Registrant and Mellon Investor Services, LLC, as Rights
                      Agent, and the exhibits thereto (3)
               10.87  Agreement dated January 12, 2001 between James J. Peterson
                      and the Registrant* (4)
               10.88  Agreement dated January 12, 2001 between David R. Sonksen
                      and the Registrant* (4)
               ---------
               *Indicates that the exhibit contains a management compensatory
                plan or arrangement.

                (1) Filed in Registration Statement (No. 33-3845) and
                    incorporated herein by this reference.

                (2) Incorporated by reference to the indicated Exhibit to the
                    Registrant's Current Report on Form 8-K as filed on August
                    29, 2001.

                (3) Incorporated by reference to the indicated Exhibit to the
                    Registrant's Registration Statement of Form 8-A12G as filed
                    December 29, 2000.

                (4) Incorporated by reference to the indicated Exhibit to the
                    Registrant's Quarterly Report on Form 10-Q as filed on
                    February 13, 2001 with the Commission for the fiscal quarter
                    ended December 31, 2000.

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                                   SIGNATURES

Pursuant to the requirements of Section 12 of the Securities Exchange Act of
1934, the registrant has duly caused this registration statement to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                        MICROSEMI CORPORATION
                                        (Registrant)



Date: February 11, 2002                 By:  /s/ James J. Peterson
                                            ------------------------------------
                                                  James J. Peterson,
                                                Chief Executive Officer
                                                     and President

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