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                                                                     EXHIBIT 3.1

                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                              ELGAR HOLDINGS, INC.

                  The undersigned, Kenneth R. Kilpatrick and Christopher W.
Kelford, hereby certify that:

                  1.       They are the President and Chief Executive Officer,
and Vice President--Finance, Chief Financial Officer, Treasurer and Assistant
Secretary, respectively, of Elgar Holdings, Inc., a Delaware corporation (the
"Corporation").

                  2.       Section 4.01 is hereby deleted and a Section 4.01 is
hereby inserted, which shall read in its entirety as follows:

          "SECTION 4.01  The total number of shares of stock which the
     Corporation shall have authority to issue is fifteen million fifty thousand
     (15,050,000) shares of capital stock, consisting of:

                  (A)      Fifteen million shares (15,000,000) of common stock,
         par value $0.01 per share ("Common Stock"), entitled to vote at any
         annual or special meeting of the stockholders of the Corporation. Each
         share of Common Stock shall have one (1) vote on any and all matters
         that may come before the stockholders of the Corporation at any annual
         or special meeting. Upon the effectiveness of this Certificate of
         Amendment to the Certificate of Incorporation of the Corporation, each
         outstanding share of the common stock, par value $0.01 per share, shall
         be split into two (2) shares of Common Stock, par value $0.01 per
         share.

                  (B)      Fifty thousand (50,000) shares of preferred stock,
         par value $0.01 per share ("Preferred Stock"). The Board of Directors
         is authorized, subject to limitations prescribed by law, to provide for
         the issuance of the shares of Preferred Stock in one or more series,
         and by filing a certificate pursuant to the applicable law of the State
         of Delaware, to establish from time to time the number of shares to be
         included in each such series, and to fix the designation, powers,
         preferences and rights of the shares of each such series and the
         qualifications, limitations or restrictions thereof. The number of
         shares of authorized shares of Preferred Stock may be increased or
         decreased (but not below the number of shares thereof then outstanding)
         by the affirmative vote of the holders of a majority of the Common
         Stock, without a vote of the holders of the Preferred
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         Stock, or of any series thereof, unless a vote of any such holders
         is required pursuant to the certificate or certificates establishing
         the series of Preferred Stock.

                  The authority of the Board of Directors with respect to each
         such series shall include, but not be limited to, determination of the
         following:

                           (1)      The number of shares constituting that
                  series and the distinctive designation of that series;

                           (2)      The dividend rate on the shares of that
                  series, whether dividends shall be cumulative, and, if so,
                  from which date or dates, and the relative rights of priority,
                  if any, of payment of dividends on shares of that series;

                           (3)      Whether that series shall have voting
                  rights, in addition to the voting rights provided by law, and,
                  if so, the terms of such voting rights;

                           (4)      Whether that series shall have conversion
                  privileges, and, if so, the terms and conditions of such
                  conversion, including provisions for adjustment of the
                  conversion rate in such events as the Board of Directors shall
                  determine;

                           (5)      Whether or not the shares of that series
                  shall be redeemable, and, if so, the terms and conditions of
                  such redemption, including, the date or dates upon or after
                  which they shall be redeemable, and the amount per share
                  payable in case of redemption, which amount may vary under
                  different conditions and at different redemption dates;

                           (6)      Whether that series shall have a sinking
                  fund for the redemption or purchase of shares of that series,
                  and, if so, the terms and amount of such sinking fund;

                           (7)      The rights of the shares of that series in
                  the event of a voluntary or involuntary liquidation,
                  dissolution or winding up of the Corporation, and the relative
                  rights of priority, if any, of payment of shares of that
                  series;

                           (8)      Any other relative rights, preferences and
                  limitations of that series."

                  3.       The foregoing Certificate of Amendment has been duly
approved by the Board of Directors of the Corporation.

                  4.       The foregoing Certificate of Amendment has been duly
approved by the required vote of stockholders of the Corporation in accordance
with the applicable provisions of Sections 228 and 242 of the Delaware General
Corporation Law. The total number of shares voting in favor of the Certificate
of Amendment equaled or exceeded the vote required. The percentage vote required
was greater than 50%.

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                  The undersigned declare under penalty of perjury under the
laws of the State of Delaware that the matters set forth in this Certificate of
Amendment are true and correct of their own knowledge.

Dated:   July 31, 2000

                               /s/ KENNETH R. KILPATRICK
                               -----------------------------------------------
                               Kenneth R. Kilpatrick
                               President and Chief Executive Officer

                               /s/ CHRISTOPHER W. KELFORD
                               -----------------------------------------------
                               Christopher W. Kelford
                               Vice President--Finance, Chief Financial Officer,
                                  Treasurer and Assistant Secretary

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