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                                                                     Exhibit 3.1

                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                               VIRATA CORPORATION

         Virata Corporation, a Delaware corporation (the "Corporation"), does
hereby certify that:

         FIRST: The name of the Corporation is Virata Corporation and that the
Corporation was originally incorporated on August 31, 1999, pursuant to the
General Corporation Law, under the name Virata Corporation.

         SECOND:  The Certificate of Incorporation of the Corporation shall be
amended and restated to read in full as follows:


                                    ARTICLE I
                               NAME OF CORPORATION

         The name of this corporation is Virata Corporation.

                                   ARTICLE II
                                REGISTERED OFFICE

         The address of the registered office of the corporation in the State of
Delaware is 9 East Loockerman Street, in the City of Dover 19901, County of
Kent, and the name of its registered agent at that address is National
Registered Agents, Inc.

                                   ARTICLE III
                                     PURPOSE

         The purpose of the corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of Delaware.

                                   ARTICLE IV
                            AUTHORIZED CAPITAL STOCK

         The total number of shares of stock which the corporation shall have
authority to issue is Forty-Five Million (45,000,000), Forty Million
(40,000,000) of which shall be designated shares of Common Stock, par value of
one-tenth of one cent ($0.001) per share (the "Common Stock"), and Five Million
(5,000,000) of which shall be designated shares of Preferred Stock, par value of
one-tenth of one cent ($0.001) per share (the "Preferred Stock"). Effective
immediately upon the filing of this Restated and Amended Certificate of
Incorporation, every share of Common Stock outstanding prior to such effective
date shall be deemed to be converted into and reconstituted as 0.1492537 shares
of Common Stock.
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         Authority is hereby expressly granted to the Board of Directors from
time to time to create one or more series of Preferred Stock and to issue
Preferred Stock in series, and in connection with the designation of any such
series, by resolution or resolutions providing for the issue of shares of such
series, to determine and fix such voting powers, full or limited, or lack of
voting powers, and such designations, powers, preferences and rights of the
shares of each such series and the qualifications, limitations or restrictions
thereof including, without limitation, dividend rights, conversion rights,
redemption privileges and liquidation preferences, all to the full extent now or
hereafter permitted by law. Without limiting the generality of the foregoing,
the resolutions providing for issuance of any series of Preferred Stock may
provide that such series shall be superior or rank equally or be junior to the
Preferred Stock of any other series to the extent permitted by law. No vote of
the holders of the Preferred Stock or Common Stock shall be a prerequisite to
the issuance of any shares of any series of Preferred Stock authorized by and
complying with the conditions of the Certificate of Incorporation, unless
provided in the Certificate of Incorporation or in any designation creating any
series.

                                    ARTICLE V
                          BOARD POWER REGARDING BYLAWS

         In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to make, repeal, alter,
amend and rescind the bylaws of the corporation.

                                   ARTICLE VI
                   NUMBER OF DIRECTORS; ELECTION OF DIRECTORS

         The number of directors which will constitute the whole Board of
Directors of the corporation shall be specified in the bylaws of the
corporation. Elections of directors need not be by written ballot unless the
bylaws of the corporation shall so provide.

                                   ARTICLE VII
                        LIMITATION OF DIRECTOR LIABILITY

         To the fullest extent permitted by the Delaware General Corporation Law
as the same exists or may hereafter be amended, a director of the corporation
shall not be liable to the corporation or its stockholders for monetary damages
for breach of fiduciary duty as a director. If the Delaware General Corporation
Law is amended after the date of the filing of this Certificate of Incorporation
to authorize corporate action further eliminating or limiting the personal
liability of directors, then the liability of a director of the corporation
shall be eliminated or limited to the fullest extent permitted by the Delaware
General Corporation Law, as so amended from time to time. No repeal or
modification of this Article VIII by the stockholders shall adversely affect any
right or protection of a director of the corporation existing by virtue of this
Article VIII at the time of such repeal or modification. In furtherance of this
Article VIII, the Board of Directors is authorized to enter into indemnification
agreements with its directors or officers.
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                                  ARTICLE VIII
                                 CORPORATE POWER

         The corporation reserves the right to amend, alter, change or repeal
any provision contained in this Certificate of Incorporation, in the manner now
or hereafter prescribed by statute, and all rights conferred on stockholders
herein are granted subject to this reservation.

                                   ARTICLE IX
                       CREDITOR COMPROMISE OR ARRANGEMENT

         Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code, order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as a consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.

                                      * * *

         THIRD: The foregoing Amended and Restated Certificate of Incorporation
was duly adopted by this Corporation's Board of Directors and stockholders in
accordance with the provisions of Sections 228, 242 and 245 of the General
Corporation Law.

                  [Remainder of page intentionally left blank.]
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         IN WITNESS WHEREOF, the undersigned has executed this Amended and
Restated Certificate of Incorporation on November 17, 1999.

                                /s/ Andrew M. Vought
                                --------------------------------
                                Andrew Vought
                                Chief Financial Officer, Vice President, Finance
                                and Secretary