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                                                                   EXHIBIT 3.(i)

                             AMENDED AND RESTATED
                             --------------------
                          CERTIFICATE OF INCORPORATION
                          ----------------------------
                                       OF
                                       --
                                 CARDIMA, INC.
                                 -------------
                             A Delaware corporation
                       (Pursuant to Sections 242 and 245
                    of the Delaware General Corporation Law)

     CARDIMA, INC., a corporation organized and existing under and by virtue of
the General Corporation Law of the State of Delaware, hereby certifies as
follows:

     FIRST:  That the name of the corporation is Cardima, Inc. and that the
corporation was originally incorporated on November 12, 1992 pursuant to the
General Corporation Law.

     SECOND:  The Amended and Restated Certificate of Incorporation of this
corporation shall be restated to read in full as follows:

                                   "ARTICLE I

     The name of this corporation is Cardima, Inc.

                                   ARTICLE II

     The address of the registered office of this corporation in the State of
Delaware is 1013 Centre Road, City of Wilmington, County of New Castle, Delaware
19805. The name of its registered agent at such address is Corporation Service
Company.

                                  ARTICLE III

     The nature of the business or purposes to be conducted or promoted is to
engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware.

                                   ARTICLE IV

     This corporation is authorized to issue two classes of stock to be
designated common stock ("Common Stock") and preferred stock ("Preferred
Stock"). The total number of shares which the Corporation is authorized to issue
is Thirty Million (30,000,000) shares. The number of shares of Common Stock
authorized to be issued is Twenty-Five Million (25,000,000), par value $0.001
per share, and the number of shares of Preferred Stock authorized to be issued
is Five Million (5,000,000), par value $0.001 per share.

     The Preferred Stock may be issued from time to time in one or more series,
without further stockholder approval. The Board of Directors is hereby
authorized, in the resolution or resolutions adopted by the Board of Directors
providing for the issuance of any wholly unissued series of Preferred Stock,
within the limitations and restrictions stated in this Amended and Restated
Certificate of Incorporation, to fix or alter the dividend rights, dividend
rate, conversion

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rights, 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 Preferred Stock, and the number of shares
constituting any such series and the designation thereof, or any of them, and 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 that they had
prior to the adoption of the resolution originally fixing the number of shares
of such series.

                                   ARTICLE V

     Except as otherwise provided in this Amended and Restated Certificate of
Incorporation, 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 any or all of the Bylaws of this corporation.

                                   ARTICLE VI

     The number of directors of this corporation shall be fixed from time to
time by a bylaw or amendment thereof duly adopted by the Board of Directors or
by the stockholders.

                                  ARTICLE VII

     Elections of directors need not be by written ballot unless the Bylaws of
this corporation shall so provide.

                                  ARTICLE VIII

     Meetings of stockholders may be held within or without the State of
Delaware, as the Bylaws may provide. The books of this corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the Bylaws of this corporation.

                                   ARTICLE IX

     A director of this corporation shall, to the full extent permitted by the
Delaware General Corporation Law as it now exists or as it may hereafter be
amended, not be liable to this corporation or its stockholders for monetary
damages for breach of fiduciary duty as a director. Neither any amendment nor
repeal of this Article, nor the adoption of any provision of this Amended and
Restated Certificate of Incorporation inconsistent with this Article, shall
eliminate or reduce the effect of this Article in respect of any matter
occurring, or any cause of action, suit or claim that, but for this Article,
would accrue or arise, prior to such amendment, repeal or adoption of an
inconsistent provision.

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                                   ARTICLE X

     No action required to be taken or that may be taken at any annual or
special meeting of the stockholders of this corporation may be taken without a
meeting, and the power of stockholders to consent in writing, without a meeting,
to the taking of any action is specifically denied.

                                   ARTICLE XI

     To the fullest extent permitted by applicable law, this corporation is
authorized to provide indemnification of (and advancement of expenses to) its
agents (and any other persons to which Delaware law permits this corporation to
provide indemnification) through Bylaw provisions, agreements with such agents
or other persons, vote of stockholders or disinterested directors or otherwise,
in excess of the indemnification and advancement otherwise permitted by Section
145 of the Delaware General Corporation Law, subject only to limits created by
applicable Delaware law (statutory or non-statutory), with respect to actions
for breach of duty to this corporation, its stockholders, and others.

     Any repeal or modification of any of the foregoing provisions of this
Article shall not adversely affect any right or protection of a director,
officer, agent or other person existing at the time of, or increase the
liability of any director of this corporation with respect to any acts or
omissions of such director, officer, agent or other person occurring prior to
such repeal or modification.

                                  ARTICLE XII

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

                                     * * *

     THIRD:  That thereafter said amendment and restatement was duly adopted in
accordance with the provisions of Section 242 and Section 245 of the Delaware
General Corporation Law by obtaining a majority vote of each of the Common Stock
and Preferred Stock, in favor of said amendment and restatement in the manner
set forth in Section 228 of the Delaware General Corporation Law.

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     IN WITNESS WHEREOF, CARDIMA, INC. has caused this Amended and Restated
Certificate of Incorporation to be signed by its President and attested to by
its Secretary this 22nd day of April, 1997.


                              CARDIMA, INC.


                              ------------------------------------------
                              /s/ Phillip C. Radlick, Ph.D.
                              Phillip C. Radlick, Ph.D.
                              President and Chief Executive Officer

ATTEST



/s/ Joshua L. Green
--------------------------------
Joshua L. Green, Secretary

                          CERTIFICATE OF AMENDMENT OF
                          ---------------------------

              AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF
              ----------------------------------------------------

                                 CARDIMA, INC.
                                 -------------

     Cardima, Inc., a corporation organized and existing under the laws of the
State of Delaware, hereby certifies as follows:

     FIRST:  The name of the Corporation is Cardima, Inc..

     SECOND:  The date of filing of its original Certificate of Incorporation
with the Secretary of State of Delaware was November 12, 1992.

     THIRD:  At a meeting of the Board of Directors of Cardima, Inc.,
resolutions were duly adopted providing that:

     (i) Article IV of the Certificate of Incorporation of Cardima, Inc., as
amended, shall be hereby amended and restated to read as follows:

                                  "ARTICLE IV

          "This corporation is authorized to issue two classes of stock to be
     designated common stock ("Common Stock") and preferred ("Preferred Stock").
     The total number of shares which the Corporation is authorized to issue is
     Fifty Five Million (55,000,000)

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     shares. The number of shares of Common Stock authorized to be issued is
     Fifty Million (50,000,000), par value $0.001 per share, and the number of
     shares of Preferred Stock authorized to be issued is Five Million
     (5,000,000), par value $0.001 per share.

          The Preferred Stock may be issued from time to time in one or more
     series, without further stockholder approval. The Board of Directors is
     hereby authorized, in the resolution or resolutions adopted by the Board of
     Directors providing for the issuance of any wholly unissued series of
     Preferred Stock, within the limitations and restrictions stated in this
     Amended and Restated Certificate of Incorporation, to fix or alter the
     dividend rights, dividend rate conversion rights, 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 Preferred Stock, and the number of shares constituting any such
     series and the designation thereof, or any of them, and 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 or 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
     that they had prior to the adoption of the resolution originally fixing the
     number of shares of such series."

     FOURTH:  That thereafter, pursuant to resolution of its Board of Directors,
a meeting of the stockholders of said corporation was duly called and held, upon
notice in accordance with Section 222 of the General Corporation Law of the
State of Delaware, at which meeting the necessary number of shares as required
by statute were voted in favor of the amendment.

     FIFTH:  This Certificate of Amendment of Certificate of Incorporation was
duly adopted at said annual meeting of the stockholders in accordance with the
provisions of section 242 of the General Corporation Law of the State of
Delaware.


     IN WITNESS WHEREOF, said Cardima, Inc. has caused this certificate to be
signed by its President and Chief Executive Officer, Phillip C. Radlick, Ph.D.
this 16th day of June, 2000.

                                    By /s/ Phillip C. Radlick, Ph.D.
                                       -----------------------------
                                         Phillip C. Radlick, Ph.D.
                                    President and Chief Executive Officer

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