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                                                                    EXHIBIT 10.2
                               SYNPLICITY, INC.

                       1995 STOCK OPTION PLAN AS AMENDED
                   AND RESTATED EFFECTIVE DECEMBER 15, 1999

  1.  Purposes of the Plan.  The purposes of this Stock Option Plan are to
      --------------------
attract and retain the best available personnel for positions of substantial
responsibility, to provide additional incentive to Employees and Consultants of
the Company and its Subsidiaries and to promote the success of the Company's
business. Options granted under the Plan may be incentive stock options (as
defined under Section 422 of the Code) or non-statutory stock options, as
determined by the Administrator at the time of grant of an option and subject to
the applicable provisions of Section 422 of the Code, as amended, and the
regulations promulgated thereunder.

  2.  Definitions.  As used herein, the following definitions shall apply:
      -----------

      (a) "Administrator" means the Board or any of its Committees appointed
           -------------
pursuant to Section 4 of the Plan.

      (b) "Board" means the Board of Directors of the Company.
           -----

      (c) "Code" means the Internal Revenue Code of 1986, as amended.
           ----

      (d) "Committee"  means a Committee appointed by the Board of Directors in
           ---------
accordance with Section 4 of the Plan.

      (e) "Common Stock" means the Common Stock of the Company.
           ------------

      (f) "Company" means Synplicity, Inc., a California corporation.
           -------

      (g) "Consultant" means any person, including an advisor, who is engaged
           ----------
by the Company or any Parent or Subsidiary to render services and is compensated
for such services, and any director of the Company whether compensated for such
services or not provided that if and in the event the Company registers any
class of any equity security pursuant to the Exchange Act, the term Consultant
shall thereafter not include directors who are not compensated for their
services or are paid only a director's fee by the Company.

      (h) "Continuous Status as an Employee or Consultant"  means that the
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employment or consulting relationship is not interrupted or terminated by the
Company, any Parent or Subsidiary. Continuous Status as an Employee or
Consultant shall not be considered interrupted in the case of: (i) any leave of
absence approved by the Company, including sick leave, military leave, or any
other personal leave; provided, however, that for purposes of Incentive Stock
Options, any such leave may not exceed ninety (90) days, unless reemployment
upon the expiration of such leave is guaranteed by contract (including certain
Company policies) or statute; provided, further, that on the ninety-first day of
any such leave (where reemployment is not guaranteed by contract or statute) an
Optionee's Incentive Stock Option shall automatically convert to a Nonstatutory
Stock Option; or (ii) transfers between locations of the Company or between the
Company, its Parent, its Subsidiaries or its successor.

      (i) "Disability" means total and permanent disability as defined in
           ----------
Section 22(e)(3) of the Code.

      (j) "Employee" means any person, including officers and directors,
           --------
employed by the Company or any Parent or Subsidiary of the Company. The payment
of a director's fee by the Company shall not be sufficient to constitute
"employment" by the Company.

      (k) "Exchange Act" means the Securities Exchange Act of 1934, as amended.
           ------------

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      (l) "Fair Market Value" means, as of any date, the value of Common Stock
           -----------------
determined as follows:

          (i)   If the Common Stock is listed on any established stock exchange
or a national market system including without limitation the National Market
System of the National Association of Securities Dealers, Inc. Automated
Quotation ("NASDAQ") System, its Fair Market Value shall be the closing sales
price for such stock (or the closing bid, if no sales were reported, as quoted
on such exchange or system for the last market trading day prior to the time of
determination) as reported in The Wall Street Journal or such other source as
the Administrator deems reliable;

          (ii)  If the Common Stock is quoted on the NASDAQ System (but not on
the National Market System thereof) or regularly quoted by a recognized
securities dealer but selling prices are not reported, its Fair Market Value
shall be the mean between the high bid and low asked prices for the Common Stock
or;

          (iii) In the absence of an established market for the Common Stock,
the Fair Market Value thereof shall be determined in good faith by the
Administrator.

      (m) "Incentive Stock Option" means an Option intended to qualify as an
           ----------------------
incentive stock option within the meaning of Section 422 of the Code.

      (n) "Nonstatutory Stock Option" means an Option not intended to qualify as
           -------------------------
an Incentive Stock Option.

      (o) "Option" means a stock option granted pursuant to the Plan.
           ------

      (p) "Optioned Stock" means the Common Stock subject to an Option.
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      (q) "Optionee" means an Employee or Consultant who receives an Option.
           --------

      (r) "Parent" means a "parent corporation", whether now or hereafter
           ------
existing, as defined in Section 424(e) of the Code.

      (s) "Plan" means this 1995 Stock Option Plan as Amended and Restated
           ----
Effective April 28, 1998.

      (t) "Share" means a share of the Common Stock, as adjusted in accordance
           -----
with Section 18 below.

      (u) "Subsidiary" means a "subsidiary corporation", whether now or
           ----------
hereafter existing, as defined in Section 424(f) of the Code.

  3.  Stock Subject to the Plan. Subject to the provisions of Section 11 of the
      -------------------------
Plan, the maximum aggregate number of shares which may be optioned and sold
under the Plan is eleven million one hundred thousand (11,100,000) shares of
Common Stock. The shares may be authorized, but unissued, or reacquired Common
Stock.

      If an Option should expire or become unexercisable for any reason without
having been exercised in full, the unpurchased Shares which were subject thereto
shall, unless the Plan shall have been terminated, become available for future
grant under the Plan.

  4.  Administration of the Plan.
      --------------------------

      (a)  Initial Plan Procedure. Prior to the date, if any, upon which the
           ----------------------
Company becomes subject to the Exchange Act, the Plan shall be administered by
the Board or a committee appointed by the Board.

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      (b)  Plan Procedure After the Date, if any, Upon Which the Company Becomes
           ---------------------------------------------------------------------
Subject to the Exchange Act.
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           (i)    Administration With Respect to Directors and Officers. With
                  -----------------------------------------------------
respect to grants of Options to Employees who are also officers or directors of
the Company, the Plan shall be administered by (A) the Board if the Board may
administer the Plan in compliance with Rule 16b-3 promulgated under the Exchange
Act or any successor thereto ("Rule 16b-3") with respect to a plan intended to
qualify thereunder as a discretionary plan, or (B) a committee designated by the
Board to administer the Plan, which committee shall be constituted in such a
manner as to permit the Plan to comply with Rule 16b-3 with respect to a plan
intended to qualify thereunder as a discretionary plan. Once appointed, such
Committee shall continue to serve in its designated capacity until otherwise
directed by the Board. From time to time the Board may increase the size of the
Committee and appoint additional members thereof, remove members (with or
without cause) and appoint new members in substitution therefor, fill vacancies,
however caused, and remove all members of the Committee and thereafter directly
administer the Plan, all to the extent permitted by Rule 16b-3 with respect to a
plan intended to qualify thereunder as a discretionary plan.

           (ii)   Multiple Administrative Bodies. If permitted by Rule 16b-3,
                  ------------------------------
the Plan may be administered by different bodies with respect to directors, non-
director officers and Employees who are neither directors nor officers.

           (iii)  Administration With Respect to Consultants and Other
                  ----------------------------------------------------
Employees. With respect to grants of Options to Employees or Consultants who are
---------
neither directors nor officers of the Company, the Plan shall be administered by
(A) the Board or (B) a committee designated by the Board, which committee shall
be constituted in such a manner as to satisfy the legal requirements relating to
the administration of incentive stock option plans, if any, of California
corporate and securities laws, of the Code, and of any applicable stock exchange
(the "Applicable Laws"). Once appointed, such Committee shall continue to serve
in its designated capacity until otherwise directed by the Board. From time to
time the Board may increase the size of the Committee and appoint additional
members thereof, remove members (with or without cause) and appoint new members
in substitution therefor, fill vacancies, however caused, and remove all members
of the Committee and thereafter directly administer the Plan, all to the extent
permitted by the Applicable Laws.

      (c)  Powers of the Administrator. Subject to the provisions of the Plan
           ---------------------------
and in the case of a Committee, the specific duties delegated by the Board to
such Committee, and subject to the approval of any relevant authorities,
including the approval, if required, of any stock exchange upon which the Common
Stock is listed, the Administrator shall have the authority, in its discretion:

           (i)   to determine the Fair Market Value of the Common Stock, in
accordance with Section 2(l) of the Plan;

           (ii)  to select the Consultants and Employees to whom Options may
from time to time be granted hereunder;

           (iii) to determine whether and to what extent Options are granted
hereunder;

           (iv)  to determine the number of shares of Common Stock to be covered
by each such award granted hereunder;

           (v)   to approve forms of agreement for use under the Plan;

           (vi)  to determine the terms and conditions, not inconsistent with
the terms of the Plan, of any award granted hereunder. Such terms and conditions
include, but are not limited to, the time or times when Options may be exercised
(which may be based on performance criteria), any vesting acceleration or waiver
of forfeiture restrictions, and any restriction or limitation regarding any
Option or the shares of Common Stock relating thereto, based in each case on
such factors as the Administrator, in its sole discretion, shall determine;

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           (vii)   to determine whether and under what circumstances an Option
may be settled in cash under subsection 9(f) instead of Common Stock;

           (viii)  to reduce the exercise price of any Option to the then
current Fair Market Value if the Fair Market Value of the Common Stock covered
by such Option shall have declined since the date the Option was granted; and

           (ix)    to construe and interpret the terms of the Plan and awards
granted pursuant to the Plan.

      (d)  Effect of Administrator's Decision. All decisions, determinations and
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interpretations of the Administrator shall be final and binding on all Optionees
and any other holders of any Options.

  5.  Eligibility.
      -----------

      (a)  Nonstatutory Stock Options may be granted to Employees and
Consultants. Incentive Stock Options may be granted only to Employees. An
Employee or Consultant who has been granted an Option may, if otherwise
eligible, be granted additional Options.

      (b)  Each Option shall be designated in the written option agreement as
either an Incentive Stock Option or a Nonstatutory Stock Option. However,
notwithstanding such designations, to the extent that the aggregate Fair Market
Value of the Shares with respect to which Options designated as Incentive Stock
Options are exercisable for the first time by any Optionee during any calendar
year (under all plans of the Company or any Parent or Subsidiary) exceeds
$100,000, such excess Options shall be treated as Nonstatutory Stock Options.

      (c)  For purposes of Section 5(b), Incentive Stock Options shall be taken
into account in the order in which they were granted, and the Fair Market Value
of the Shares shall be determined at the time such Options are granted.

      (d)  The Plan shall not confer upon any Optionee any right with respect to
continuation of employment relationship with the Company, nor shall it interfere
in any way with his or her right or the Company's right to terminate his or her
employment relationship at any time, with or without cause.

  6.  Term of Plan. The Plan shall become effective upon the earlier to occur of
      ------------
its adoption by the Board of Directors or its approval by the shareholders of
the Company as described in Section 17 of the Plan. It shall continue in effect
for a term of ten (10) years unless sooner terminated under Section 13 of the
Plan.

  7.  Term of Option. The term of each Option shall be the term stated in the
      --------------
Option Agreement; provided, however, that the term shall be no more than ten
(10) years from the date of grant thereof. However, in the case of an Incentive
Stock Option granted to an Optionee who, at the time the Option is granted, owns
stock representing more than ten percent (10%) of the voting power of all
classes of stock of the Company or any Parent or Subsidiary, the term of the
Option shall be five (5) years from the date of grant thereof or such shorter
term as may be provided in the Option Agreement.

  8.  Option Exercise Price and Consideration.
      ---------------------------------------

      (a)  The per share exercise price for the Shares to be issued pursuant to
exercise of an Option shall be such price as is determined by the Board, but
shall be subject to the following:

           (i)   In the case of an Incentive Stock Option

                 (A)  granted to an Employee who, at the time of the grant of
such Incentive Stock Option, owns stock representing more than ten percent (10%)
of the voting power of all classes of stock of the

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Company or any Parent or Subsidiary, the per Share exercise price shall be no
less than 110% of the Fair Market Value per Share on the date of grant.

                 (B)  granted to any Employee, the per Share exercise price
shall be no less than 100% of the Fair Market Value per Share on the date of
grant.

           (ii)  In the case of a Nonstatutory Stock Option, the per Share
exercise price shall be determined by the Administrator.

      (b)  The consideration to be paid for the Shares to be issued upon
exercise of an Option, including the method of payment, shall be determined by
the Administrator (and, in the case of an Incentive Stock Option, shall be
determined at the time of grant) and may consist entirely of (1) cash, (2)
check, (3) promissory note, (4) other Shares which (x) in the case of Shares
acquired upon exercise of an Option, have been owned by the Optionee for more
than six months on the date of surrender, and (y) have a Fair Market Value on
the date of surrender equal to the aggregate exercise price of the Shares as to
which said Option shall be exercised, (5) delivery of a properly executed
exercise notice together with such other documentation as the Administrator and
the broker, if applicable, shall require to effect an exercise of the Option and
delivery to the Company of the sale or loan proceeds required to pay the
exercise price, (6) any combination of the foregoing methods of payment, (7) or
such other consideration as the Administrator deems acceptable. In making its
determination as to the type of consideration to accept, the Administrator shall
consider if acceptance of such consideration may be reasonably expected to
benefit the Company.

  9.  Exercise of Option.
      ------------------

      (a)  Procedure for Exercise; Rights as a Shareholder. Any Option granted
           -----------------------------------------------
hereunder shall be exercisable at such times and under such conditions as
determined by the Administrator and as set forth in the Notice of Grant,
including performance criteria with respect to the Company and/or the Optionee,
and as shall be permissible under the terms of the Plan.

           An Option may not be exercised for a fraction of a Share.

           An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company. Full payment may, as authorized by the Board, consist of any
consideration and method of payment allowable under Section 8(b) of the Plan.
Until the issuance (as evidenced by the appropriate entry on the books of the
Company or of a duly authorized transfer agent of the Company) of the stock
certificate evidencing such Shares, no right to vote or receive dividends or any
other rights as a shareholder shall exist with respect to the Optioned Stock,
notwithstanding the exercise of the Option. The Company shall issue (or cause to
be issued) such stock certificate promptly upon exercise of the Option. No
adjustment will be made for a dividend or other right for which the record date
is prior to the date the stock certificate is issued, except as provided in
Section 11 of the Plan.

           Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be available, both for purposes of the
Plan and for sale under the Option, by the number of Shares as to which the
Option is exercised.

      (b)  Termination of Employment. In the event of termination of an
           -------------------------
Optionee's Continuous Status as an Employee or Consultant with the Company (but
not in the event of a change of status from Employee to Consultant (in which
case an Employee's Incentive Stock Option shall be treated as a Nonstatutory
Stock Option on the day that is three months and one day following such change
of status) or from Consultant to Employee), such Optionee may, but only within
such period as is set forth in the Option Agreement, (and in no event later than
the expiration date of the term of such Option as set forth in the Option
Agreement), exercise his or her Option to the extent that Optionee was vested at
the date of such termination and to the extent that such Option is or becomes

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exercisable during such period. To the extent that Optionee was not vested in
the Option at the date of such termination, or if Optionee does not exercise
such Option to the extent so entitled within the time specified in the Option
Agreement, the Option shall terminate.

      (c)  Disability of Optionee.  In the event of termination of an Optionee's
           ----------------------
Continuous Status as an Employee or Consultant as a result of Disability,
Optionee may, but only within such period as is set forth in the Option
Agreement, (and in no event later than the expiration date of the term of such
Option as set forth in the Option Agreement), exercise his or her Option to the
extent that Optionee was vested at the date of such termination and to the
extent that such Option is or becomes exercisable during such period. However,
if such exercise occurs more than twelve (12) months from the date of
termination, an Employee's Incentive Stock Option shall be treated as a
Nonstatutory Stock Option. To the extent that Optionee was not vested at the
date of such termination, or if Optionee does not exercise such Option to the
extent so entitled within the time specified in the Option Agreement, the Option
shall terminate.

      (d)  Death of Optionee. In the event of termination of an Optionee's
           -----------------
Continuous Status as an Employee or Consultant as a result of the death of an
Optionee, the Option may be exercised, but only within such period as is set
forth in the Option Agreement, (and in no event later than the expiration date
of the term of such Option as set forth in the Option Agreement), to the extent
that such Option is or becomes exercisable during such period, by the Optionee's
estate or by a person who acquired the right to exercise the Option by bequest
or inheritance, but only to the extent that the Option was vested at the date of
death. To the extent that the Option was not vested at the date of death, or if
the Option is not exercised to the extent entitled within the time specified in
the Option Agreement, the Option shall terminate.

      (e)  Rule 16b-3. Options granted to persons subject to Section 16(b) of
           ----------
the Exchange Act must comply with Rule 16b-3 and shall contain such additional
conditions or restrictions as may be required thereunder to qualify for the
maximum exemption from Section 16 of the Exchange Act with respect to Plan
transactions.

      (f)  Buyout Provisions. The Administrator may at any time offer to buy out
           -----------------
for a payment in cash or Shares, an Option previously granted, based on such
terms and conditions as the Administrator shall establish and communicate to the
Optionee at the time that such offer is made.

  10. Non-Transferability of Options. Options may not be sold, pledged,
      ------------------------------
assigned, hypothecated, transferred, or disposed of in any manner other than by
will or by the laws of descent or distribution and may be exercised, during the
lifetime of the Optionee, only by the Optionee.

  11. Adjustments Upon Changes in Capitalization, Dissolution, Liquidation,
      ---------------------------------------------------------------------
Merger or Asset Sale.
--------------------

      (a)  Changes in Capitalization.  Subject to any required action by the
           -------------------------
shareholders of the Company, the number of shares of Common Stock covered by
each outstanding Option, and the number of shares of Common Stock which have
been authorized for issuance under the Plan but as to which no Options have yet
been granted or which have been returned to the Plan upon cancellation or
expiration of an Option, as well as the price per share of Common Stock covered
by each such outstanding Option, shall be proportionately adjusted for any
increase or decrease in the number of issued shares of Common Stock resulting
from a stock split, reverse stock split, stock dividend, combination or
reclassification of the Common Stock, or any other increase or decrease in the
number of issued shares of Common Stock effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration." Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issuance by the Company of shares of
stock of any class, or securities convertible into shares of stock of any class,
shall affect, and no adjustment by reason thereof shall be made with respect to,
the number or price of shares of Common Stock subject to an Option.

      (b)  Dissolution or Liquidation. In the event of the proposed dissolution
           --------------------------
or liquidation of the Company, the Board shall notify the Optionee at least
fifteen (15) days prior to such proposed action. To the extent

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it has not been previously exercised, the Option will terminate immediately
prior to the consummation of such proposed action.

       (c)  Merger or Asset Sale. In the event of a merger of the Company with
            --------------------
or into another corporation, or the sale of substantially all of the assets of
the Company, the Option shall be assumed or an equivalent option shall be
substituted by such successor corporation or a parent or subsidiary of such
successor corporation. If such merger or sale of substantially all of the assets
of the Company occurs within twelve months after the Vesting Commencement Date,
the Option as assumed or the equivalent substituted option shall be vested as to
1/48 of the Shares for each month since the Vesting Commencement Date, but only
if Optionee is a Consultant or Employee of the Company as of the date of the
closing of the merger or asset sale, and only if so provided in an Optionee's
individual Option Agreement. In the event that the successor corporation does
not agree to assume the Option or to substitute an equivalent option, the
Administrator shall, if so provided in an Optionee's individual Option
Agreement, in lieu of such assumption or substitution, provide for the Optionee
to have the right to exercise the Option as to all of the Optioned Stock,
including Shares as to which it would not otherwise be exercisable, but only if
Optionee is a Consultant or Employee of the Company as of the date of the
closing of the merger or asset sale. If not so provided in an Optionee's
individual Option Agreement, the Option shall terminate as of the date of the
closing of the merger or asset sale.

  For the purposes of this section, the Option shall be considered assumed if,
following the merger or sale of assets, the Option confers the right to
purchase, for each Share of Optioned Stock subject to the Option immediately
prior to the merger, the consideration (whether stock, cash, or other securities
or property) received in the merger or sale of assets by holders of Common Stock
for each Share held on the effective date of the transaction (and if holders
were offered a choice of consideration, the type of consideration chosen by the
holders of a majority of the outstanding Shares); provided, however, that if
such consideration received in the merger or sale of assets was not solely
common stock of the successor corporation or its Parent, the Administrator may,
with the consent of the successor corporation and the participant, provide for
the consideration to be received upon the exercise of the Option, for each Share
of Optioned Stock subject to the Option, to be solely common stock of the
successor corporation or its Parent equal in fair market value to the per share
consideration received by holders of Common Stock in the merger or sale of
assets.

  12.  Time of Granting Options.  The date of grant of an Option shall,
       ------------------------
for all purposes, be the date on which the Administrator makes the determination
granting such Option, or such other date as is determined by the Administrator.
Notice of the determination shall be given to each Employee or Consultant to
whom an Option is so granted within a reasonable time after the date of such
grant.

  13.  Amendment and Termination of the Plan.
       -------------------------------------

       (a)  Amendment and Termination. The Board may at any time amend, alter,
            -------------------------
suspend or discontinue the Plan, but no amendment, alteration, suspension or
discontinuation shall be made which would impair the rights of any Optionee
under any grant theretofore made, without his or her consent. In addition, to
the extent necessary and desirable to comply with Rule 16b-3 under the Exchange
Act or with Section 422 of the Code (or any other applicable law or regulation,
including the requirements of the NASD or an established stock exchange), the
Company shall obtain shareholder approval of any Plan amendment in such a manner
and to such a degree as required.

       (b)  Effect of Amendment or Termination. Any such amendment or
            ----------------------------------
termination of the Plan shall not affect Options already granted and such awards
shall remain in full force and effect as if this Plan had not been amended or
terminated, unless mutually agreed otherwise between the Optionee and the Board,
which agreement must be in writing and signed by the Optionee and the Company.

  14.  Conditions Upon Issuance of Shares. Shares shall not be issued pursuant
       ----------------------------------
to the exercise of an Option unless the exercise of such award and the issuance
and delivery of such Shares pursuant thereto shall comply with all relevant
provisions of law, including, without limitation, the Securities Act of 1933, as
amended, the Exchange Act, the rules and regulations promulgated thereunder, and
the requirements of any stock exchange upon

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which the Shares may then be listed, and shall be further subject to the
approval of counsel for the Company with respect to such compliance.

       As a condition to the exercise of an Option, the Company may require the
person exercising such award to represent and warrant at the time of any such
exercise that the Shares are being purchased only for investment and without any
present intention to sell or distribute such Shares if, in the opinion of
counsel for the Company, such a representation is required by any of the
aforementioned relevant provisions of law.

  15.  Reservation of Shares. The Company, during the term of this Plan, will at
       ---------------------
all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

       The inability of the Company to obtain authority from any regulatory body
having jurisdiction, which authority is deemed by the Company's counsel to be
necessary to the lawful issuance and sale of any Shares hereunder, shall relieve
the Company of any liability in respect of the failure to issue or sell such
Shares as to which such requisite authority shall not have been obtained.

  16.  Agreements.  Options shall be evidenced by written agreements in such
       ----------
form as the Board shall approve from time to time.

  17.  Shareholder Approval.  Options issued under the Plan shall be subject to
       --------------------
approval of the Plan by the shareholders of the Company within twelve (12)
months before or after the date the Plan is adopted. Such shareholder approval
shall be obtained in the degree and manner required under applicable state and
federal law and the rules of any stock exchange upon which the Common Stock is
listed.

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