EXHIBIT 3.3


                            CERTIFICATE OF AMENDMENT
                             OF AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                      OF APPLIED MICRO CIRCUITS CORPORATION


      Applied Micro Circuits Corporation, a corporation organized and existing
under and by virtue of the General Corporation Law of the State of Delaware,
does hereby certify:

      FIRST: The name of the Corporation is Applied Micro Circuits Corporation
(the "Corporation").

      SECOND: The date on which the Corporation's original Certificate of
Incorporation was filed with the Delaware Secretary of State is February 6,
1987.

      THIRD: The Board of Directors of the Corporation, acting in accordance
with the provision of Sections 141 and 242 of the General Corporation Law of the
State of Delaware adopted resolutions at a meeting held on April 19, 2000 to
amend the first paragraph of Article IV of the Amended and Restated Certificate
of Incorporation of the Corporation to read in its entirety as follows:

      (A) This Corporation is authorized to issue 632,000,000 shares of its
      Capital Stock, which shall be divided into two classes known as Common
      Stock and Preferred Stock, respectively.

      (B) The total number of shares of Common Stock which this Corporation is
      authorized to issue is 630,000,000 with a par value of $0.01 per share.
      The total number of shares of Preferred Stock which this Corporation is
      authorized to issue is 2,000,000 with a par value of $0.01 per share. The
      Preferred Stock may be issued from time to time in one or more series. The
      Board of Directors of this Corporation is hereby authorized, within the
      limitations and restrictions prescribed by law or stated in this
      Certificate of Incorporation, and by filing a certificate pursuant to
      applicable law of the State of Delaware, to provide for the issuance of
      Preferred Stock in series and (i) to establish from time to time the
      number of shares to be included in each such series; (ii) to fix the
      voting powers, designations, powers, preferences and relative,
      participating, optional or other rights of the shares of each such series
      and the qualifications, limitations or restrictions thereof, including but
      not limited to, the fixing or alteration of the dividend rights, dividend
      rate, conversion rights, conversion rates, voting rights, rights and terms
      of redemption (including sinking fund provisions), the redemption price or
      prices, and the liquidation preferences of any wholly unissued series of
      shares of Preferred Stock; and (iii) to increase or decrease the number of
      shares of any series subsequent to the issue of shares of that series, but
      not below the number of shares of such series then outstanding. In case
      the number of shares of any series shall be so decreased, the shares
      constituting such decrease shall resume the status which they had prior to
      the adoption of the resolution originally fixing the number of shares of
      such series.


      FOURTH: Thereafter, pursuant to a resolution of the Board of Directors,
this Certificate of Amendment of Amended and Restated Certificate of
Incorporation was submitted to the stockholders of the Corporation and was duly
approved by the required vote of stockholders of the Corporation in accordance
with Sections 228 and 242 of the Delaware General Corporation Law. The total
number of outstanding shares entitled to vote or consent to this Amendment was
124,624,285 shares of Common Stock. A majority of the outstanding shares of
Common Stock voted in favor of this Certificate of Amendment of Amended and
Restated Certificate of Incorporation.

      IN WITNESS WEREOF, the Corporation has caused this Certificate of
Amendment to be signed by its President and Chief Executive Officer this 30th
day of August 2000.

                                        Applied Micro Circuits Corporation


                                        /s/ David M. Rickey
                                        -------------------------------------
                                        David M. Rickey
                                        President and Chief Executive Officer


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