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                                                                    EXHIBIT 10.9

                               PDF SOLUTIONS, INC.

                                 1997 STOCK PLAN

                   (amended and restated as of June 30, 2000)

        1. PURPOSES OF THE PLAN. The purposes of this 1997 Stock 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 nonstatutory 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. Stock purchase rights may also be granted
under the Plan.

        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) "AFFILIATE" means any entity which has a business relationship
with the Company.

             (c) "BOARD" means the Board of Directors of the Company.

             (d) "CODE" means the Internal Revenue Code of 1986, as amended.

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

             (f) "COMMON STOCK" means the Common Stock of the Company.

             (g) "COMPANY" means PDF Solutions, Inc., a California corporation.

             (h) "CONSULTANT" means any person, including an advisor, who is
engaged by the Company or any Parent, Subsidiary or Affiliate 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.

             (i) "CONTINUOUS STATUS AS AN EMPLOYEE OR CONSULTANT" means the
absence of any interruption or termination of service as an Employee or
Consultant. Continuous Status as an Employee or Consultant shall not be
considered interrupted in the case of: (i) sick leave; (ii) military leave;
(iii) any other leave of absence approved by the Administrator, provided that
such leave is for a period of not more than ninety (90) days, unless
reemployment upon the expiration of such leave is guaranteed by contract or
statute, or unless provided otherwise pursuant to Company policy adopted from
time to time; or (iv) in the case of transfers between locations of the Company
or between the Company, its Subsidiaries or their respective


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successors. For purposes of this Plan, a change in status from an Employee to a
Consultant or from a Consultant to an Employee will not constitute an
interruption of Continuous Status as an Employee or Consultant.

             (j) "EMPLOYEE" means any person, including officers and directors,
employed by the Company or any Parent or Subsidiary of the Company, with the
status of employment determined based upon such minimum number of hours or
periods worked as shall be determined by the Administrator in its discretion,
subject to any requirements of the Code. The payment by the Company of a
director's fee to a Director shall not be sufficient to constitute "employment"
of such Director by the Company.

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

             (l) "FAIR MARKET VALUE" means, as of any date, the fair market
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 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 system or exchange, or the exchange with the greatest volume of trading
in Common Stock 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 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
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; 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, as
designated in the applicable written option agreement.

             (n) "NONSTATUTORY STOCK OPTION" means an Option not intended to
qualify as an Incentive Stock Option, as designated in the applicable written
option agreement.

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

             (p) "OPTIONED STOCK" means the Common Stock subject to an Option or
a Stock Purchase Right.

             (q) "OPTIONEE" means an Employee or Consultant who receives an
Option or a Stock Purchase Right.



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

             (s) "PLAN" means this 1997 Stock Plan.

             (t) "REPORTING PERSON" means an officer, director, or greater than
ten percent shareholder of the Company within the meaning of Rule 16a-2 under
the Exchange Act, who is required to file reports pursuant to Rule 16a-3 under
the Exchange Act.

             (u) "RESTRICTED STOCK" means shares of Common Stock acquired
pursuant to a grant of a Stock Purchase Right under Section 10 below.

             (v) "RULE 16b-3" means Rule 16b-3 promulgated under the Exchange
Act, as the same may be amended from time to time, or any successor provision.

             (w) "SHARE" means a share of the Common Stock, as adjusted in
accordance with Section 12 of the Plan.

             (x) "STOCK EXCHANGE" means any stock exchange or consolidated stock
price reporting system on which prices for the Common Stock are quoted at any
given time.

             (y) "STOCK PURCHASE RIGHT" means the right to purchase Common Stock
pursuant to Section 10 below.

             (z) "SUBSIDIARY" means a "subsidiary corporation," whether now or
hereafter existing, as defined in Section 424(f) of the Code, or any successor
provision.

        3. STOCK SUBJECT TO THE PLAN. Subject to the provisions of Section 12 of
the Plan, the maximum aggregate number of Shares that may be optioned and sold
under the Plan is 8,402,449 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 that were subject thereto shall, unless the Plan shall
have been terminated, become available for future grant under the Plan. In
addition, any Shares of Common Stock which are retained by the Company upon
exercise of an Option or Stock Purchase Right in order to satisfy the exercise
or purchase price for such Option or Stock Purchase Right or any withholding
taxes due with respect to such exercise shall be treated as not issued and shall
continue to be available under the Plan. Shares repurchased by the Company
pursuant to any repurchase right which the Company may have shall not be
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.

             (b) PLAN PROCEDURE AFTER THE DATE, IF ANY, UPON WHICH THE COMPANY
BECOMES SUBJECT TO THE EXCHANGE ACT.



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                    (i) MULTIPLE ADMINISTRATIVE BODIES. If permitted by Rule
16b-3, grants under the Plan may be made by different bodies with respect to
directors, non-director officers and Employees or Consultants who are not
Reporting Persons.

                    (ii) ADMINISTRATION WITH RESPECT TO REPORTING PERSONS. With
respect to grants of Options or Stock Purchase Rights to Employees who are
Reporting Persons, such grants shall be made by (A) the Board if the Board may
make grants to Reporting Persons under the Plan in compliance with Rule 16b-3,
or (B) a committee designated by the Board to make grants to Reporting Persons
under the Plan, which committee shall be constituted in such a manner as to
permit grants under the Plan to comply with Rule 16b-3. 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
make grants to Reporting Persons under the Plan, all to the extent permitted by
Rule 16b-3.

                    (iii) ADMINISTRATION WITH RESPECT TO CONSULTANTS AND OTHER
Employees. With respect to grants of Options or Stock Purchase Rights to
Employees or Consultants who are not Reporting Persons, 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, 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(k) of the Plan;

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

                    (iii) to determine whether and to what extent Options and
Stock Purchase Rights or any combination thereof 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;



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                    (vi) to determine the terms and conditions, not inconsistent
with the terms of the Plan, of any award granted hereunder;

                    (vii) to determine whether and under what circumstances an
Option may be settled in cash under Section 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;

                    (ix) to determine the terms and restrictions applicable to
Stock Purchase Rights and the Restricted Stock purchased by exercising such
Stock Purchase Rights; and

                    (x) to construe and interpret the terms of the Plan and
awards granted pursuant to the Plan; and

                    (xi) in order to fulfill the purposes of the Plan and
without amending the Plan, to modify grants of Options or Stock Purchase Rights
to participants who are foreign nationals or employed outside of the United
States in order to recognize differences in local law, tax policies or customs.

             (d) EFFECT OF ADMINISTRATOR'S DECISION. All decisions,
determinations and interpretations of the Administrator shall be final and
binding on all holders of Options or Stock Purchase Rights.

        5. ELIGIBILITY.

             (a) RECIPIENTS OF GRANTS. Nonstatutory Stock Options and Stock
Purchase Rights 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 or Stock Purchase Right may, if he or she is otherwise
eligible, be granted additional Options or Stock Purchase Rights.

             (b) TYPE OF OPTION. 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 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,
Subsidiary or Affiliate) exceeds $100,000, such excess Options shall be treated
as Nonstatutory Stock Options. For purposes of this 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 subject to an Incentive Stock
Option shall be determined as of the date of the grant of such Option.

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



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        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 19 of the Plan. It shall
continue in effect for a term of ten (10) years unless sooner terminated under
Section 15 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 or such shorter term as may be
provided in the Option Agreement and provided further that, 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 total
combined 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 written 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 and set forth in the applicable agreement, but shall be subject to the
following:

                    (i) In the case of an Incentive Stock Option that is:

                         (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 total combined voting power of all classes of stock of the
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 other 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 that is:

                         (A) granted to a person who, at the time of the grant
of such Option, owns stock representing more than ten percent (10%) of the total
combined voting power of all classes of stock of the 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 the grant.

                         (B) granted to any person, the per Share exercise price
shall be no less than 85% of the Fair Market Value per Share on the date of
grant.

             (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 that (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 or such other period as may be required
to avoid a charge to the Company's earnings, and (y) have a Fair Market Value on
the date of surrender equal to the


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aggregate exercise price of the Shares as to which such Option shall be
exercised, (5) authorization for the Company to retain from the total number of
Shares as to which the Option is exercised that number of Shares having a Fair
Market Value on the date of exercise equal to the exercise price for the total
number of Shares as to which the Option is exercised, (6) 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 and any applicable income or employment taxes, (7)
delivery of an irrevocable subscription agreement for the Shares that
irrevocably obligates the option holder to take and pay for the Shares not more
than twelve months after the date of delivery of the subscription agreement, (8)
any combination of the foregoing methods of payment, or (9) such other
consideration and method of payment for the issuance of Shares to the extent
permitted under Applicable Laws. 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 reflected in the written option
agreement, which may include vesting requirements and/or performance criteria
with respect to the Company and/or the Optionee; provided that such Option shall
become exercisable at the rate of at least twenty percent (20%) per year over
five (5) years from the date the Option is granted. In the event that any of the
Shares issued upon exercise of an Option should be subject to a right of
repurchase in the Company's favor, such repurchase right shall lapse at the rate
of at least twenty percent (20%) per year over five (5) years from the date the
Option is granted.

                    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 the
Company has received full payment for the Shares with respect to which the
Option is exercised. 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,
not withstanding 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 12 of the Plan.

                    Exercise of an Option in any manner shall result in a
decrease in the number of Shares that 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.



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             (b) TERMINATION OF EMPLOYMENT OR CONSULTING RELATIONSHIP. Subject
to Section 9(c), in the event of termination of an Optionee's Continuous Status
as an Employee or Consultant with the Company, such Optionee may, but only
within three (3) months (or such other period of time not less than thirty (30)
days as is determined by the Administrator, with such determination in the case
of an Incentive Stock Option being made at the time of grant of the Option and
not exceeding three (3) months) after the date of such termination (but 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 the
Optionee was entitled to exercise it at the date of such termination. To the
extent that Optionee was not entitled to exercise 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 herein, the Option shall terminate. No
termination shall be deemed to occur and this Section 9(b) shall not apply if
(i) the Optionee is a Consultant who becomes an Employee; or (ii) the Optionee
is an Employee who becomes a Consultant.

             (c) DISABILITY OF OPTIONEE.

                    (i) Notwithstanding Section 9(b) above, in the event of
termination of an Optionee's Continuous Status as an Employee or Consultant as a
result of his or her total and permanent disability (within the meaning of
Section 22(e)(3) of the Code), Optionee may, but only within twelve (12) months
from the date of such termination (but in no event later than the expiration
date of the term of such Option as set forth in the Option Agreement), exercise
the Option to the extent otherwise entitled to exercise it at the date of such
termination. To the extent that Optionee was not entitled to exercise the Option
at the date of termination, or if Optionee does not exercise such Option to the
extent so entitled within the time specified herein, the Option shall terminate.

                    (ii) In the event of termination of an Optionee's Continuous
Status as an Employee or Consultant as a result of a disability which does not
fall within the meaning of total and permanent disability (as set forth in
Section 22(e)(3) of the Code), Optionee may, but only within six (6) months from
the date of such termination (but in no event later than the expiration date of
the term of such Option as set forth in the Option Agreement), exercise the
Option to the extent otherwise entitled to exercise it at the date of such
termination. However, to the extent that such Optionee fails to exercise an
Option which is an Incentive Stock Option ("ISO") (within the meaning of Section
422 of the Code) within three (3) months of the date of such termination, the
Option will not qualify for ISO treatment under the Code. To the extent that
Optionee was not entitled to exercise the Option at the date of termination, or
if Optionee does not exercise such Option to the extent so entitled within six
months (6) from the date of termination, the Option shall terminate.

             (d) DEATH OF OPTIONEE. In the event of the death of an Optionee
during the period of Continuous Status as an Employee or Consultant since the
date of grant of the Option, or within thirty (30) days following termination of
Optionee's Continuous Status as an Employee or Consultant, the Option may be
exercised, at any time within six (6) months following the date of death (but in
no event later than the expiration date of the term of such Option as set forth
in the Option Agreement), by Optionee's estate or by a person who acquired the
right to exercise the Option by bequest or inheritance, but only to the extent
of the right to exercise that had accrued at the date of death or, if earlier,
the date of termination of Optionee's Continuous Status


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as an Employee or Consultant. To the extent that Optionee was not entitled to
exercise the Option at the date of death or termination, as the case may be, or
if Optionee does not exercise such Option to the extent so entitled within the
time specified herein, the Option shall terminate.

             (e) RULE 16b-3. Options granted to Reporting Persons shall comply
with Rule 16b-3 and shall contain such additional conditions or restrictions as
may be required thereunder to qualify for the maximum exemption for 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. STOCK PURCHASE RIGHTS.

             (a) RIGHTS TO PURCHASE. Stock Purchase Rights may be issued either
alone, in addition to, or in tandem with other awards granted under the Plan
and/or cash awards made outside of the Plan. After the Administrator determines
that it will offer Stock Purchase Rights under the Plan, it shall advise the
offeree in writing of the terms, conditions and restrictions related to the
offer, including the number of Shares that such person shall be entitled to
purchase, the price to be paid (which price shall not be less than 85% of the
Fair Market Value of the Shares as of the date of the offer, or, in the case of
a person owning stock representing more than ten percent (10%) of the total
combined voting power of all classes of stock of the Company or any Parent or
Subsidiary, the price shall not be less than one hundred percent (100%) of the
Fair Market Value of the Shares as of the date of the offer), and the time
within which such person must accept such offer, which shall in no event exceed
thirty (30) days from the date upon which the Administrator made the
determination to grant the Stock Purchase Right. The offer shall be accepted by
execution of a Restricted Stock purchase agreement in the form determined by the
Administrator. Shares purchased pursuant to the grant of a Stock Purchase Right
shall be referred to herein as "Restricted Stock."

             (b) REPURCHASE OPTION. Unless the Administrator determines
otherwise, the Restricted Stock purchase agreement shall grant the Company a
repurchase option exercisable upon the voluntary or involuntary termination of
the purchaser's employment with the Company for any reason (including death or
disability). The purchase price for Shares repurchased pursuant to the
Restricted Stock purchase agreement shall be the original purchase price paid by
the purchaser and may be paid by cancellation of any indebtedness of the
purchaser to the Company. The repurchase option shall lapse at such rate as the
Administrator may determine, but at a minimum rate of 20% per year.

             (c) OTHER PROVISIONS. The Restricted Stock purchase agreement shall
contain such other terms, provisions and conditions not inconsistent with the
Plan as may be determined by the Administrator in its sole discretion. In
addition, the provisions of Restricted Stock purchase agreements need not be the
same with respect to each purchaser.

             (d) RIGHTS AS A SHAREHOLDER. Once the Stock Purchase Right is
exercised, the purchaser shall have the rights equivalent to those of a
shareholder, and shall be a shareholder


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when his or her purchase is entered upon the records of the duly authorized
transfer agent of the Company. No adjustment will be made for a dividend or
other right for which the record date is prior to the date the Stock Purchase
Right is exercised, except as provided in Section 12 of the Plan.

        11. STOCK WITHHOLDING TO SATISFY WITHHOLDING TAX OBLIGATIONS. At the
discretion of the Administrator, Optionees may satisfy withholding obligations
as provided in this paragraph. When an Optionee incurs tax liability in
connection with an Option or Stock Purchase Right, which tax liability is
subject to tax withholding under applicable tax laws, and the Optionee is
obligated to pay the Company an amount required to be withheld under applicable
tax laws, the Optionee may satisfy the withholding tax obligation by one or some
combination of the following methods: (a) by cash payment, or (b) out of
Optionee's current compensation, (c) if permitted by the Administrator, in its
discretion, by surrendering to the Company Shares that (i) in the case of Shares
previously acquired from the Company, have been owned by the Optionee for more
than six months on the date of surrender, and (ii) have a fair market value on
the date of surrender equal to or less than Optionee's marginal tax rate times
the ordinary income recognized, or (d) by electing to have the Company withhold
from the Shares to be issued upon exercise of the Option, or the Shares to be
issued in connection with the Stock Purchase Right, if any, that number of
Shares having a fair market value equal to the amount required to be withheld.
For this purpose, the fair market value of the Shares to be withheld shall be
determined on the date that the amount of tax to be withheld is to be determined
(the "Tax Date").

             Any surrender by a Reporting Person of previously owned Shares to
satisfy tax withholding obligations arising upon exercise of this Option must
comply with the applicable provisions of Rule 16b-3.

             All elections by an Optionee to have Shares withheld to satisfy tax
withholding obligations shall be made in writing in a form acceptable to the
Administrator and shall be subject to the following restrictions:

             (a) the election must be made on or prior to the applicable Tax
Date;

             (b) once made, the election shall be irrevocable as to the
particular Shares of the Option or Stock Purchase Right as to which the election
is made; and

             (c) all elections shall be subject to the consent or disapproval of
the Administrator.

             In the event the election to have Shares withheld is made by an
Optionee and the Tax Date is deferred under Section 83 of the Code because no
election is filed under Section 83(b) of the Code, the Optionee shall receive
the full number of Shares with respect to which the Option or Stock Purchase
Right is exercised but such Optionee shall be unconditionally obligated to
tender back to the Company the proper number of Shares on the Tax Date.

        12. ADJUSTMENTS UPON CHANGES IN CAPITALIZATION, MERGER OR CERTAIN OTHER
TRANSACTIONS.



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             (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 or Stock Purchase Right, and the number of shares of
Common Stock that have been authorized for issuance under the Plan but as to
which no Options or Stock Purchase Rights have yet been granted or that have
been returned to the Plan upon cancellation or expiration of an Option or Stock
Purchase Right, as well as the price per share of Common Stock covered by each
such outstanding Option or Stock Purchase Right, 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, recapitalization 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 or Stock Purchase Right.

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

             (c) MERGER OR SALE OF ASSETS. In the event of a proposed sale of
all or substantially all of the Company's assets or a merger of the Company with
or into another corporation where the successor corporation issues its
securities to the Company's shareholders, each outstanding Option or Stock
Purchase Right shall be assumed or an equivalent option or right shall be
substituted by such successor corporation or a parent or subsidiary of such
successor corporation, unless the successor corporation does not agree to assume
the Option or Stock Purchase Right or to substitute an equivalent option or
right, in which case such Option or Stock Purchase Right shall terminate upon
the consummation of the merger or sale of assets.

             (d) CERTAIN DISTRIBUTIONS. In the event of any distribution to the
Company's shareholders of securities of any other entity or other assets (other
than dividends payable in cash or stock of the Company) without receipt of
consideration by the Company, the Administrator may, in its discretion,
appropriately adjust the price per share of Common Stock covered by each
outstanding Option or Stock Purchase Right to reflect the effect of such
distribution.

        13. NON-TRANSFERABILITY OF OPTIONS AND STOCK PURCHASE RIGHTS. Options
and Stock Purchase Rights 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 or purchased during the lifetime of
the Optionee or Stock Purchase Rights Holder only by the Optionee or Stock
Purchase Rights Holder.

        14. TIME OF GRANTING OPTIONS AND STOCK PURCHASE RIGHTS. The date of
grant of an Option or Stock Purchase Right shall, for all purposes, be the date
on which the Administrator


                                     - 11 -
<PAGE>   12

makes the determination granting such Option or Stock Purchase Right, or such
other date as is determined by the Board; provided however that in the case of
any Incentive Stock Option, the grant date shall be the later of the date on
which the Administrator makes the determination granting such Incentive Stock
Option or the date of commencement of the Optionee's employment relationship
with the Company. Notice of the determination shall be given to each Employee or
Consultant to whom an Option or Stock Purchase Right is so granted within a
reasonable time after the date of such grant.

        15. AMENDMENT AND TERMINATION OF THE PLAN.

             (a) AUTHORITY TO AMEND OR TERMINATE. The Board may at any time
amend, alter, suspend or discontinue the Plan, but no amendment, alteration,
suspension or discontinuation shall be made that 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 or
with Section 422 of the Code (or any other applicable law or regulation,
including the requirements of any 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. No amendment or termination
of the Plan shall adversely affect Options already granted, unless mutually
agreed otherwise between the Optionee and the Board, which agreement must be in
writing and signed by the Optionee and the Company.

        16. CONDITIONS UPON ISSUANCE OF SHARES. Shares shall not be issued
pursuant to the exercise of an Option or Stock Purchase Right unless the
exercise of such Option or Stock Purchase Right 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. As a condition to the exercise of an Option,
the Company may require the person exercising such Option 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 law.

        17. 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.

        18. AGREEMENTS. Options and Stock Purchase Rights shall be evidenced by
written agreements in such form as the Administrator shall approve from time to
time.

        19. SHAREHOLDER APPROVAL. Continuance of the Plan shall be subject to
approval by the shareholders of the Company within twelve (12) months before or
after the date the Plan is


                                     - 12 -
<PAGE>   13

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. All Options and Stock Purchase
Rights issued under the Plan shall become void in the event such approval is not
obtained.

        20. INFORMATION AND DOCUMENTS TO OPTIONEES AND PURCHASERS. The Company
shall provide financial statements at least annually to each Optionee and to
each individual who acquired Shares Pursuant to the Plan, during the period such
Optionee or purchaser has one or more Options or Stock Purchase Rights
outstanding, and in the case of an individual who acquired Shares pursuant to
the Plan, during the period such individual owns such Shares. The Company shall
not be required to provide such information if the issuance of Options or Stock
Purchase Rights under the Plan is limited to key employees whose duties in
connection with the Company assure their access to equivalent information. In
addition, at the time of issuance of any securities under the Plan, the Company
shall provide to the Optionee or the Purchaser a copy of the Plan and a copy of
the agreement(s) pursuant to which securities under the Plan are issued.



                                     - 13 -
<PAGE>   14


                               PDF SOLUTIONS, INC.

                                 1997 STOCK PLAN

                          NOTICE OF STOCK OPTION GRANT


<<Optionee>>


        You have been granted an option to purchase Common Stock ("Common
Stock") of PDF Solutions, Inc. (the "Company") as follows:

        Board Approval Date:                <<BoardApprovDate>>

        Date of Grant (Later of Board
               Approval Date or
               Commencement of
               Employment/Consulting):      <<GrantDate>>

        Vesting Commencement Date:          <<VestingCommenceDate>>

        Exercise Price Per Share:           $<<ExercisePrice>>

        Total Number of Shares Granted:     <<NoofShares>>

        Total Exercise Price:               $<<TotalExercisePrice>>

        Type of Option:                     <<Type>>

        Term/Expiration Date:               <<ExpirDate>>

        Vesting Schedule:                   <<Vesting>>


<PAGE>   15

        Termination                         Period: This Option may be exercised
                                            for 60 days after termination of
                                            employment or consulting
                                            relationship except as set out in
                                            Sections 6 and 7 of the Stock Option
                                            Agreement (but in no event later
                                            than the Expiration Date).


        By your signature and the signature of the Company's representative
below, you and the Company agree that this option is granted under and governed
by the terms and conditions of the 1997 Stock Plan and the Stock Option
Agreement, both of which are attached and made a part of this document.



<<OPTIONEE>>:                           PDF SOLUTIONS, INC.:


----------------------------------      By:
Signature
                                             P. S. Melman, CFO
----------------------------------           -----------------------------------
Print Name                                   Print Name and Title

----------------------------------
Address

----------------------------------
Address



                                     - 15 -
<PAGE>   16

                               PDF SOLUTIONS, INC.

                                 1997 STOCK PLAN

                             STOCK OPTION AGREEMENT


        1. GRANT OF OPTION. PDF Solutions, Inc., a California corporation (the
"Company"), hereby grants to <<Optionee>> ("Optionee") an option (the "Option")
to purchase a total number of shares of Common Stock (the "Shares") set forth in
the Notice of Stock Option Grant, at the exercise price per share set forth in
the Notice of Stock Option Grant (the "Exercise Price") subject to the terms,
definitions and provisions of the PDF Solutions, Inc. 1997 Stock Plan (the
"Plan") adopted by the Company, which is incorporated herein by reference.
Unless otherwise defined herein, the terms defined in the Plan shall have the
same defined meanings in this Option.

        If designated an Incentive Stock Option, this Option is intended to
qualify as an Incentive Stock Option as defined in Section 422 of the Code.

        2. EXERCISE OF OPTION. This Option shall be exercisable during its Term
in accordance with the Vesting Schedule set out in the Notice of Stock Option
Grant and with the provisions of Section 9 of the Plan as follows:

             (a) RIGHT TO EXERCISE.

             RIGHT TO EXERCISE.

                    (i) This Option may be early exercised in whole any time
after the Date of Grant (the "Early Exercise"), as to Shares which have not yet
vested under the vesting schedule indicated on the Notice of Stock Option Grant;
provided, however, that Optionee shall execute as a condition to such exercise
of this Option, the Early Exercise Notice and Restricted Stock Purchase
Agreement attached hereto as Exhibit A (the "Early Exercise Agreement"). If
Optionee chooses to exercise this Option solely as to Shares which have vested
under the vesting schedule indicated on the Notice of Stock Option Grant,
Optionee shall complete and execute the form of Exercise Notice and Restricted
Stock Purchase Agreement attached hereto as Exhibit B (the "Exercise
Agreement"). Notwithstanding the foregoing, the Company may in its discretion
prescribe or accept a different form of notice of exercise and/or stock purchase
agreement if such forms are otherwise consistent with this Agreement, the Plan
and then-applicable law.

                    (ii) This Option may not be exercised for a fraction of a
share.

                    (iii) In the event of Optionee's death, disability or other
termination of employment or consulting relationship, the exercisability of the
Option is governed by Sections 5, 6 and 7 below, subject to the limitation
contained in Section 2(a)(iv) below.

                    (iv) In no event may this Option be exercised after the
Expiration Date of this Option as set forth in the Notice of Stock Option Grant.


<PAGE>   17

             (b) METHOD OF EXERCISE. This Option shall be exercisable by
execution and delivery of the Early Exercise Agreement or the Exercise
Agreement, whichever is applicable, or of any other written notice approved for
such purpose by the Company which shall state the election to exercise the
Option, the number of Shares in respect of which the Option is being exercised,
and such other representations and agreements as to the holder's investment
intent with respect to such shares of Common Stock as may be required by the
Company pursuant to the provisions of the Plan. Such written notice shall be
signed by Optionee and shall be delivered in person or by certified mail to the
Secretary of the Company. The written notice shall be accompanied by payment of
the Exercise Price. This Option shall be deemed to be exercised upon receipt by
the Company of such written notice accompanied by the Exercise Price.

        No Shares will be issued pursuant to the exercise of an Option unless
such issuance and such exercise shall comply with all relevant provisions of
applicable law, including the requirements of any stock exchange upon which the
Shares may then be listed. Assuming such compliance, for income tax purposes the
Shares shall be considered transferred to Optionee on the date on which the
Option is exercised with respect to such Shares.

        3. METHOD OF PAYMENT. Payment of the Exercise Price shall be by cash,
check, promissory note (either in the form attached as Exhibit C to this
agreement or any other form approved by the Company), or any other method
permitted under the Plan; provided however that the Administrator may refuse to
allow Optionee to tender a particular form of payment (other than cash or check)
if, in the Administrator's sole discretion, acceptance of such form of
consideration would not be in the best interests of the Company at such time.

        4. RESTRICTIONS ON EXERCISE. This Option may not be exercised until such
time as the Plan has been approved by the shareholders of the Company, or if the
issuance of such Shares upon such exercise or the method of payment of
consideration for such shares would constitute a violation of any applicable
federal or state securities or other law or regulation, including any rule under
Part 207 of Title 12 of the Code of Federal Regulations as promulgated by the
Federal Reserve Board. As a condition to the exercise of this Option, the
Company may require Optionee to make any representation and warranty to the
Company as may be required by any applicable law or regulation.

        5. TERMINATION OF RELATIONSHIP. In the event of termination of
Optionee's Continuous Status as an Employee or Consultant, Optionee may, to the
extent otherwise so entitled at the date of such termination (the "Termination
Date"), exercise this Option during the Termination Period set forth in the
Notice of Stock Option Grant. To the extent that Optionee was not entitled to
exercise this Option at such Termination Date, or if Optionee does not exercise
this Option within the Termination Period, the Option shall terminate.

        6. DISABILITY OF OPTIONEE.

             (a) Notwithstanding the provisions of Section 5 above, in the event
of termination of Optionee's Continuous Status as an Employee or Consultant as a
result of his or her total and permanent disability (as defined in Section
22(e)(3) of the Code), Optionee may, but only within twelve months from the
Termination Date (but in no event later than the Expiration Date set forth in
the Notice of Stock Option Grant and in Section 9 below), exercise



                                     - 2 -
<PAGE>   18

this Option to the extent he or she was entitled to exercise it at such
Termination Date. To the extent that Optionee was not entitled to exercise the
Option on the Termination Date, or if Optionee does not exercise such Option to
the extent so entitled within the time specified in this Section 6(a), the
Option shall terminate.

             (b) Notwithstanding the provisions of Section 5 above, in the event
of termination of Optionee's consulting relationship or Continuous Status as an
Employee as a result of a disability not constituting a total and permanent
disability (as set forth in Section 22(e)(3) of the Code), Optionee may, but
only within six (6) months from the Termination Date (but in no event later than
the Expiration Date set forth in the Notice of Stock Option Grant), exercise the
Option to the extent Optionee was entitled to exercise it as of such Termination
Date; provided, however, that if this is an Incentive Stock Option and Optionee
fails to exercise this Incentive Stock Option within three (3) months from the
Termination Date, this Option will cease to qualify as an Incentive Stock Option
(as defined in Section 422 of the Code) and Optionee will be treated for federal
income tax purposes as having received ordinary income at the time of such
exercise in an amount generally measured by the difference between the Exercise
Price for the Shares and the Fair Market Value of the Shares on the date of
exercise. To the extent that Optionee was not entitled to exercise the Option at
the Termination Date, or if Optionee does not exercise such Option to the extent
so entitled within the time specified in this Section 6(b), the Option shall
terminate.

        7. DEATH OF OPTIONEE. In the event of the death of Optionee (a) during
the Term of this Option and while an Employee or Consultant of the Company and
having been in Continuous Status as an Employee or Consultant since the date of
grant of the Option, or (b) within 30 days after Optionee's Termination Date,
the Option may be exercised at any time within six months following the date of
death (but in no event later than the Expiration Date set forth in the Notice of
Stock Option Grant and in Section 9 below), by Optionee's estate or by a person
who acquired the right to exercise the Option by bequest or inheritance, but
only to the extent of the right to exercise that had accrued at the Termination
Date.

        8. NON-TRANSFERABILITY OF OPTION. This Option may not be transferred in
any manner otherwise than by will or by the laws of descent or distribution and
may be exercised during the lifetime of Optionee only by him or her. The terms
of this Option shall be binding upon the executors, administrators, heirs,
successors and assigns of Optionee.

        9. TERM OF OPTION. This Option may be exercised only within the Term set
forth in the Notice of Stock Option Grant, subject to the limitations set forth
in Section 7 of the Plan.

        10. TAX CONSEQUENCES. Set forth below is a brief summary as of the date
of this Option of certain of the federal and California tax consequences of
exercise of this Option and disposition of the Shares under the laws in effect
as of the Date of Grant. THIS SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX
LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. OPTIONEE SHOULD CONSULT A TAX
ADVISER BEFORE EXERCISING THIS OPTION OR DISPOSING OF THE SHARES.

             (a) EXERCISE OF INCENTIVE STOCK OPTION. If this Option qualifies as
an Incentive Stock Option, there will be no regular federal or California income
tax liability upon


                                     - 3 -
<PAGE>   19

the exercise of the Option, although the excess, if any, of the Fair Market
Value of the Shares on the date of exercise over the Exercise Price will be
treated as an adjustment to the alternative minimum tax for federal tax purposes
and may subject Optionee to the alternative minimum tax in the year of exercise.

             (b) EXERCISE OF NONSTATUTORY STOCK OPTION. If this Option does not
qualify as an Incentive Stock Option, there may be a regular federal income tax
liability and a California income tax liability upon the exercise of the Option.
Optionee will be treated as having received compensation income (taxable at
ordinary income tax rates) equal to the excess, if any, of the fair market value
of the Shares on the date of exercise over the Exercise Price. If Optionee is an
employee, the Company will be required to withhold from Optionee's compensation
or collect from Optionee and pay to the applicable taxing authorities an amount
equal to a percentage of this compensation income at the time of exercise.

             (c) DISPOSITION OF SHARES. In the case of a Nonstatutory Stock
Option, if Shares are held for more than one year, any gain realized on
disposition of the Shares will be treated as long-term capital gain for federal
and California income tax purposes. In the case of an Incentive Stock Option, if
Shares transferred pursuant to the Option are held for more than one year after
exercise and are disposed of at least two years after the Date of Grant, any
gain realized on disposition of the Shares will also be treated as long-term
capital gain for federal and California income tax purposes. In either case, the
long-term capital gain will be taxed for federal income tax and alternative
minimum tax purposes at a maximum rate of 20% if the Shares are held more than
one year after exercise. If Shares purchased under an Incentive Stock Option are
disposed of within one-year after exercise or within two years after the Date of
Grant, any gain realized on such disposition will be treated as compensation
income (taxable at ordinary income rates) to the extent of the difference
between the Exercise Price and the lesser of (i) the Fair Market Value of the
Shares on the date of exercise, or (ii) the sale price of the Shares.

             (d) NOTICE OF DISQUALIFYING DISPOSITION OF INCENTIVE STOCK OPTION
SHARES. If the Option granted to Optionee herein is an Incentive Stock Option,
and if Optionee sells or otherwise disposes of any of the Shares acquired
pursuant to the Incentive Stock Option on or before the later of (i) the date
two years after the Date of Grant, or (ii) the date one year after the date of
exercise, Optionee shall immediately notify the Company in writing of such
disposition. Optionee acknowledges and agrees that he or she may be subject to
income tax withholding by the Company on the compensation income recognized by
Optionee from the early disposition by payment in cash or out of the current
earnings paid to Optionee.

             11. WITHHOLDING TAX OBLIGATIONS.

             (a) GENERAL WITHHOLDING OBLIGATIONS. As a condition to the exercise
of Option granted hereunder, Optionee shall make such arrangements as the
Administrator may require for the satisfaction of any federal, state, local or
foreign withholding tax obligations that may arise in connection with the
exercise, receipt or vesting of the Option. The Company shall not be required to
issue any Shares under the Plan until such obligations are satisfied. Optionee
understands that, upon exercising a Nonstatutory Stock Option, he or she will
recognize income for tax purposes in an amount equal to the excess of the then
Fair Market Value of the Shares over the Exercise Price. If Optionee is an
employee, the Company will be required to withhold


                                     - 4 -
<PAGE>   20

from Optionee's compensation, or collect from Optionee and pay to the applicable
taxing authorities an amount equal to a percentage of this compensation income.
Additionally, Optionee may at some point be required to satisfy tax withholding
obligations with respect to the disqualifying disposition of an Incentive Stock
Option. Optionee shall satisfy his or her tax withholding obligation arising
upon the exercise of this Option by one or some combination of the following
methods: (i) by cash or check payment, (ii) out of Optionee's current
compensation, (iii) if permitted by the Administrator, in its discretion, by
surrendering to the Company Shares which (A) in the case of Shares previously
acquired from the Company, have been owned by Optionee for more than six months
on the date of surrender, and (B) have a Fair Market Value determined as of the
applicable Tax Date (as defined in Section 11(c) below) on the date of surrender
equal to the amount required to be withheld, or (iv) by electing to have the
Company withhold from the Shares to be issued upon exercise of the Option, or
the Shares to be issued in connection with the Stock Purchase Right, if any,
that number of Shares having a Fair Market Value determined as of the applicable
Tax Date equal to the amount required to be withheld. If the Administrator
allows the withholding or surrender of Shares to satisfy a Participant's tax
withholding obligations, the Administrator shall not allow Shares to be withheld
in an amount that exceeds the minimum statutory withholding rates for federal
and state tax purposes, including payroll taxes.

             (b) STOCK WITHHOLDING TO SATISFY WITHHOLDING TAX OBLIGATIONS. In
the event the Administrator allows Optionee to satisfy his or her tax
withholding obligations as provided in Section 11(a)(iii) or (iv) above, such
satisfaction must comply with the requirements of this Section (11)(b) and all
applicable laws. All elections by Optionee to have Shares withheld to satisfy
tax withholding obligations shall be made in writing in a form acceptable to the
Administrator and shall be subject to the following restrictions:

                    (i) the election must be made on or prior to the applicable
Tax Date (as defined in Section 11(c) below);

                    (ii) once made, the election shall be irrevocable as to the
particular Shares of the Option as to which the election is made; and

                    (iii) all elections shall be subject to the consent or
disapproval of the Administrator.

        In the event the election to have Shares withheld is made by Optionee
and the Tax Date is deferred under Section 83 of the Code because no election is
filed under Section 83(b) of the Code, Optionee shall receive the full number of
Shares with respect to which the Option is exercised but Optionee shall be
unconditionally obligated to tender back to the Company the proper number of
Shares on the Tax Date.

             (c) DEFINITIONS. For purposes of this Section 11, the Fair Market
Value of the Shares to be withheld shall be determined on the date that the
amount of tax to be withheld is to be determined under the applicable laws (the
"Tax Date").

        12. MARKET STANDOFF AGREEMENT. In connection with the initial public
offering of the Company's securities and upon request of the Company or the
underwriters managing such


                                     - 5 -
<PAGE>   21

underwritten offering of the Company's securities, Optionee agrees not to sell,
make any short sale of, loan, grant any option for the purchase of, or otherwise
dispose of any securities of the Company (other than those included in the
registration) without the prior written consent of the Company or such
underwriters, as the case may be, for such period of time (not to exceed 180
days) from the effective date of such registration as may be requested by the
Company or such managing underwriters and to execute an agreement reflecting the
foregoing as may be requested by the underwriters at the time of the Company's
initial public offering.



                            [Signature Page Follows]



                                     - 6 -
<PAGE>   22

        This Agreement may be executed in two or more counterparts, each of
which shall be deemed an original and all of which together shall constitute one
document.



                                       PDF Solutions, Inc.

                                       By:
                                          ---------------------------------

                                       Name:  P. S. Melman
                                            -------------------------------
                                             (print)

                                       Title: Chief Financial Officer
                                             ------------------------------

        OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO
THE OPTION HEREOF IS EARNED ONLY BY CONTINUING CONSULTANCY OR EMPLOYMENT AT THE
WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS
OPTION OR ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES
THAT NOTHING IN THIS AGREEMENT, NOR IN THE COMPANY'S STOCK PLAN WHICH IS
INCORPORATED HEREIN BY REFERENCE, SHALL CONFER UPON OPTIONEE ANY RIGHT WITH
RESPECT TO CONTINUATION OF EMPLOYMENT OR CONSULTANCY BY THE COMPANY, NOR SHALL
IT INTERFERE IN ANY WAY WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE OPTIONEE'S EMPLOYMENT OR CONSULTANCY AT ANY TIME, WITH OR WITHOUT
CAUSE.

        Optionee acknowledges receipt of a copy of the Plan and represents that
he or she is familiar with the terms and provisions thereof, and hereby accepts
this Option subject to all of the terms and provisions thereof. Optionee has
reviewed the Plan and this Option in their entirety, has had an opportunity to
obtain the advice of counsel prior to executing this Option and fully
understands all provisions of the Option. Optionee hereby agrees to accept as
binding, conclusive and final all decisions or interpretations of the
Administrator upon any questions arising under the Plan or this Option.


Dated:
      ---------------------------      -----------------------------------------
                                            <<Optionee>>

                                       -----------------------------------------
                                       Address 1

                                       -----------------------------------------
                                       Address 2



                                     - 7 -
<PAGE>   23

                                    EXHIBIT A

                               PDF SOLUTIONS, INC.

                                 1997 STOCK PLAN

          EARLY EXERCISE NOTICE AND RESTRICTED STOCK PURCHASE AGREEMENT

        This Agreement ("Agreement") is made as of ______________, by and
between PDF Solutions, Inc. a California corporation (the "Company"), and
<<Optionee>> ("Purchaser"). To the extent any capitalized terms used in this
Agreement are not defined, they shall have the meaning ascribed to them in the
1997 Stock Plan.

        1. EXERCISE OF OPTION. Subject to the terms and conditions hereof,
Purchaser hereby elects to exercise his or her option to purchase ______________
shares of the Common Stock (the "Shares") of the Company under and pursuant to
the Company's 1997 Stock Plan (the "Plan") and the Stock Option Agreement dated
______________ (the "Option Agreement"). Of these Shares, Purchaser has elected
to purchase _______________ of those Shares which have become vested as of the
date hereof under the Vesting Schedule set forth in the Notice of Stock Option
Grant (the "Vested Shares") and _____________ Shares which have not yet vested
under such Vesting Schedule (the "Unvested Shares"). The purchase price for the
Shares shall be $<<ExercisePrice>> per Share for a total purchase price of
$_______________. The term "Shares" refers to the purchased Shares and all
securities received in replacement of the Shares or as stock dividends or
splits, all securities received in replacement of the Shares in a
recapitalization, merger, reorganization, exchange or the like, and all new,
substituted or additional securities or other properties to which Purchaser is
entitled by reason of Purchaser's ownership of the Shares.

        2. TIME AND PLACE OF EXERCISE. The purchase and sale of the Shares under
this Agreement shall occur at the principal office of the Company simultaneously
with the execution and delivery of this Agreement in accordance with the
provisions of Section 2(b) of the Option Agreement. On such date, the Company
will deliver to Purchaser a certificate representing the Shares to be purchased
by Purchaser (which shall be issued in Purchaser's name) against payment of the
purchase price therefor by Purchaser by (a) check made payable to the Company,
(b) cancellation of indebtedness of the Company to Purchaser, (c) delivery of
shares of the Common Stock of the Company in accordance with Section 3 of the
Option Agreement, (d) delivery of a promissory note in the form attached as
Exhibit C to the Option Agreement (or in any form acceptable to the Company), or
(e) a combination of the foregoing. If Purchaser delivers a promissory note as
partial or full payment of the purchase price, Purchaser will also deliver a
Pledge and Security Agreement in the form attached to Exhibit D to the Option
Agreement (or in any form acceptable to the Company).

        3. LIMITATIONS ON TRANSFER. In addition to any other limitation on
transfer created by applicable securities laws, Purchaser shall not assign,
encumber or dispose of any interest in the Shares while the Shares are subject
to the Company's Repurchase Option (as defined below). After any Shares have
been released from such Repurchase Option, Purchaser shall not assign,



                                     - 9 -
<PAGE>   24

encumber or dispose of any interest in such Shares except in compliance with the
provisions below and applicable securities laws.

             (a) REPURCHASE OPTION.

                    (i) In the event of the voluntary or involuntary termination
of Purchaser's employment or consulting relationship with the Company for any
reason (including death or disability), with or without cause, the Company shall
upon the date of such termination (the "Termination Date") have an irrevocable,
exclusive option (the "Repurchase Option") for a period of 90 days from such
date to repurchase all or any portion of the Shares held by Purchaser as of the
Termination Date which have not yet been released from the Company's Repurchase
Option at the original purchase price per Share specified in Section 1 (adjusted
for any stock splits, stock dividends and the like).

                    (ii) Unless the Company notifies Purchaser within 90 days
from the date of termination of Purchaser's employment or consulting
relationship that it does not intend to exercise its Repurchase Option with
respect to some or all of the Shares, the Repurchase Option shall be deemed
automatically exercised by the Company as of the 90th day following such
termination, provided that the Company may notify Purchaser that it is
exercising its Repurchase Option as of a date prior to such 90th day. Unless
Purchaser is otherwise notified by the Company pursuant to the preceding
sentence that the Company does not intend to exercise its Repurchase Option as
to some or all of the Shares to which it applies at the time of termination,
execution of this Agreement by Purchaser constitutes written notice to Purchaser
of the Company's intention to exercise its Repurchase Option with respect to all
Shares to which such Repurchase Option applies. The Company, at its choice, may
satisfy its payment obligation to Purchaser with respect to exercise of the
Repurchase Option by either (A) delivering a check to Purchaser in the amount of
the purchase price for the Shares being repurchased, or (B) in the event
Purchaser is indebted to the Company, canceling an amount of such indebtedness
equal to the purchase price for the Shares being repurchased, or (C) by a
combination of (A) and (B) so that the combined payment and cancellation of
indebtedness equals such purchase price. In the event of any deemed automatic
exercise of the Repurchase Option pursuant to this Section 3(a)(ii) in which
Purchaser is indebted to the Company, such indebtedness equal to the purchase
price of the Shares being repurchased shall be deemed automatically canceled as
of the 90th day following termination of Purchaser's employment or consulting
relationship unless the Company otherwise satisfies its payment obligations. As
a result of any repurchase of Shares pursuant to this Section 3(a), the Company
shall become the legal and beneficial owner of the Shares being repurchased and
shall have all rights and interest therein or related thereto, and the Company
shall have the right to transfer to its own name the number of Shares being
repurchased by the Company, without further action by Purchaser.

                    (iii) One hundred percent (100%) of the Shares shall
initially be subject to the Repurchase Option. The Unvested Shares shall be
released from the Repurchase Option in accordance with the Vesting Schedule set
forth in the Notice of Stock Option Grant until all Shares are released from the
Repurchase Option. Fractional shares shall be rounded to the nearest whole
share.



                                     - 2 -
<PAGE>   25

             (b) RIGHT OF FIRST REFUSAL. Before any Shares held by Purchaser or
any transferee of Purchaser (either being sometimes referred to herein as the
"Holder") may be sold or otherwise transferred (including transfer by gift or
operation of law), the Company or its assignee(s) shall have a right of first
refusal to purchase the Shares on the terms and conditions set forth in this
Section 3(b) (the "Right of First Refusal").

                    (i) NOTICE OF PROPOSED TRANSFER. The Holder of the Shares
shall deliver to the Company a written notice (the "Notice") stating: (i) the
Holder's bona fide intention to sell or otherwise transfer such Shares; (ii) the
name of each proposed purchaser or other transferee ("Proposed Transferee");
(iii) the number of Shares to be transferred to each Proposed Transferee; and
(iv) the terms and conditions of each proposed sale or transfer. The Holder
shall offer the Shares at the same price (the "Offered Price") and upon the same
terms (or terms as similar as reasonably possible) to the Company or its
assignee(s).

                    (ii) EXERCISE OF RIGHT OF FIRST REFUSAL. At any time within
thirty 30 days after receipt of the Notice, the Company and/or its assignee(s)
may, by giving written notice to the Holder, elect to purchase all, but not less
than all, of the Shares proposed to be transferred to any one or more of the
Proposed Transferees, at the purchase price determined in accordance with
subsection (iii) below.

                    (iii) PURCHASE PRICE. The purchase price ("Purchase Price")
for the Shares purchased by the Company or its assignee(s) under this Section
3(b) shall be the Offered Price. If the Offered Price includes consideration
other than cash, the cash equivalent value of the non-cash consideration shall
be determined by the Board of Directors of the Company in good faith.

                    (iv) PAYMENT. Payment of the Purchase Price shall be made,
at the option of the Company or its assignee(s), in cash (by check), by
cancellation of all or a portion of any outstanding indebtedness of the Holder
to the Company (or, in the case of repurchase by an assignee, to the assignee),
or by any combination thereof within 30 days after receipt of the Notice or in
the manner and at the times set forth in the Notice.

                    (v) HOLDER'S RIGHT TO TRANSFER. If all of the Shares
proposed in the Notice to be transferred to a given Proposed Transferee are not
purchased by the Company and/or its assignee(s) as provided in this Section
3(b), then the Holder may sell or otherwise transfer such Shares to that
Proposed Transferee at the Offered Price or at a higher price, provided that
such sale or other transfer is consummated within 60 days after the date of the
Notice and provided further that any such sale or other transfer is effected in
accordance with any applicable securities laws and the Proposed Transferee
agrees in writing that the provisions of this Section 3 shall continue to apply
to the Shares in the hands of such Proposed Transferee. If the Shares described
in the Notice are not transferred to the Proposed Transferee within such period,
or if the Holder proposes to change the price or other terms to make them more
favorable to the Proposed Transferee, a new Notice shall be given to the
Company, and the Company and/or its assignees shall again be offered the Right
of First Refusal before any Shares held by the Holder may be sold or otherwise
transferred.

                                     - 3 -
<PAGE>   26

                    (vi) EXCEPTION FOR CERTAIN FAMILY TRANSFERS. Anything to the
contrary contained in this Section 3(b) notwithstanding, the transfer of any or
all of the Shares during Purchaser's lifetime or on Purchaser's death by will or
intestacy to Purchaser's Immediate Family (as defined below) or a trust for the
benefit of Purchaser's Immediate Family shall be exempt from the provisions of
this Section 3(b). "Immediate Family" as used herein shall mean spouse, lineal
descendant or antecedent, father, mother, brother or sister. In such case, the
transferee or other recipient shall receive and hold the Shares so transferred
subject to the provisions of this Section, and there shall be no further
transfer of such Shares except in accordance with the terms of this Section 3.

             (c) INVOLUNTARY TRANSFER.

                    (i) COMPANY'S RIGHT TO PURCHASE UPON INVOLUNTARY TRANSFER.
In the event, at any time after the date of this Agreement, of any transfer by
operation of law or other involuntary transfer (including divorce or death, but
excluding, in the event of death, a transfer to Immediate Family as set forth in
Section 3(b)(vi) above) of all or a portion of the Shares by the record holder
thereof, the Company shall have the right to purchase all of the Shares
transferred at the greater of the purchase price paid by Purchaser pursuant to
this Agreement or the Fair Market Value of the Shares on the date of transfer.
Upon such a transfer, the person acquiring the Shares shall promptly notify the
Secretary of the Company of such transfer. The right to purchase such Shares
shall be provided to the Company for a period of 30 days following receipt by
the Company of written notice by the person acquiring the Shares.

                    (ii) PRICE FOR INVOLUNTARY TRANSFER. With respect to any
stock to be transferred pursuant to Section 3(c)(i), the price per Share shall
be a price set by the Board of Directors of the Company that will reflect the
current value of the stock in terms of present earnings and future prospects of
the Company. The Company shall notify Purchaser or his or her executor of the
price so determined within 30 days after receipt by it of written notice of the
transfer or proposed transfer of Shares. However, if the Purchaser does not
agree with the valuation as determined by the Board of Directors of the Company,
the Purchaser shall be entitled to have the valuation determined by an
independent appraiser to be mutually agreed upon by the Company and the
Purchaser and whose fees shall be borne equally by the Company and the
Purchaser.

             (d) ASSIGNMENT. The right of the Company to purchase any part of
the Shares may be assigned in whole or in part to any shareholder or
shareholders of the Company or other persons or organizations.

             (e) RESTRICTIONS BINDING ON TRANSFEREES. All transferees of Shares
or any interest therein will receive and hold such Shares or interest subject to
the provisions of this Agreement, including, insofar as applicable, the
Repurchase Option. In the event of any purchase by the Company hereunder where
the Shares or interest are held by a transferee, the transferee shall be
obligated, if requested by the Company, to transfer the Shares or interest to
the Purchaser for consideration equal to the amount to be paid by the Company
hereunder. In the event the Repurchase Option is deemed exercised by the Company
pursuant to Section 3(a)(ii) hereof, the Company may deem any transferee to have
transferred the Shares or interest to Purchaser prior to their purchase by the
Company, and payment of the purchase price by the


                                     - 4 -
<PAGE>   27

Company to such transferee shall be deemed to satisfy Purchaser's obligation to
pay such transferee for such Shares or interest, and also to satisfy the
Company's obligation to pay Purchaser for such Shares or interest. Any sale or
transfer of the Shares shall be void unless the provisions of this Agreement are
satisfied.

             (f) TERMINATION OF RIGHTS. The Right of First Refusal and the
Company's right to repurchase the Shares in the event of an involuntary transfer
pursuant to Section 3(c) above shall terminate upon the first sale of Common
Stock of the Company to the general public pursuant to a registration statement
filed with and declared effective by the Securities and Exchange Commission
under the Securities Act of 1933, as amended (the "Securities Act").

             (g) MARKET STANDOFF AGREEMENT. In connection with the initial
public offering of the Company's securities and upon request of the Company or
the underwriters managing such underwritten offering of the Company's
securities, Purchaser agrees not to sell, make any short sale of, loan, grant
any option for the purchase of, or otherwise dispose of any securities of the
Company (other than those included in the registration) without the prior
written consent of the Company or such underwriters, as the case may be, for
such period of time (not to exceed 180 days) from the effective date of such
registration as may be requested by the Company or such managing underwriters
and to execute an agreement reflecting the foregoing as may be requested by the
underwriters at the time of the Company's initial public offering.

        4. ESCROW OF UNVESTED SHARES. For purposes of facilitating the
enforcement of the provisions of Section 3 above, Purchaser agrees, immediately
upon receipt of the certificate(s) for the Shares subject to the Repurchase
Option, to deliver such certificate(s), together with an Assignment Separate
from Certificate in the form attached to this Agreement as Attachment A executed
by Purchaser and by Purchaser's spouse (if required for transfer), in blank, to
the Secretary of the Company, or the Secretary's designee, to hold such
certificate(s) and Assignment Separate from Certificate in escrow and to take
all such actions and to effectuate all such transfers and/or releases as are in
accordance with the terms of this Agreement. Purchaser hereby acknowledges that
the Secretary of the Company, or the Secretary's designee, is so appointed as
the escrow holder with the foregoing authorities as a material inducement to
make this Agreement and that said appointment is coupled with an interest and is
accordingly irrevocable. Purchaser agrees that said escrow holder shall not be
liable to any party hereof (or to any other party). The escrow holder may rely
upon any letter, notice or other document executed by any signature purported to
be genuine and may resign at any time. Purchaser agrees that if the Secretary of
the Company, or the Secretary's designee, resigns as escrow holder for any or no
reason, the Board of Directors of the Company shall have the power to appoint a
successor to serve as escrow holder pursuant to the terms of this Agreement.

        5. INVESTMENT AND TAXATION REPRESENTATIONS. In connection with the
purchase of the Shares, Purchaser represents to the Company the following:

             (a) Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the Shares. Purchaser is
purchasing the Shares for investment for his or her own account only and not
with a view to, or for resale in connection with, any


                                     - 5 -
<PAGE>   28

"distribution" thereof within the meaning of the Securities Act. Purchaser does
not have any present intention to transfer the Shares to any other person or
entity.

             (b) Purchaser understands that the Shares have not been registered
under the Securities Act by reason of a specific exemption therefrom, which
exemption depends upon, among other things, the bona fide nature of Purchaser's
investment intent as expressed herein.

             (c) Purchaser understands that the Shares are "restricted
securities" under applicable U.S. federal and state securities laws and that,
pursuant to these laws, Purchaser must hold the Shares indefinitely unless they
are registered with the Securities and Exchange Commission and qualified by
state authorities, or an exemption from such registration and qualification
requirements is available. Purchaser acknowledges that the Company has no
obligation to register or qualify the Shares for resale. Purchaser further
acknowledges that if an exemption from registration or qualification is
available, it may be conditioned on various requirements including, but not
limited to, the time and manner of sale, the holding period for the Shares, and
requirements relating to the Company which are outside of the Purchaser's
control, and which the Company is under no obligation and may not be able to
satisfy.

             (d) Purchaser understands that Purchaser may suffer adverse tax
consequences as a result of Purchaser's purchase or disposition of the Shares.
Purchaser represents that Purchaser has consulted any tax consultants Purchaser
deems advisable in connection with the purchase or disposition of the Shares and
that Purchaser is not relying on the Company for any tax advice.

        6. RESTRICTIVE LEGENDS AND STOP-TRANSFER ORDERS.

             (a) LEGENDS. The certificate or certificates representing the
Shares shall bear the following legends (as well as any legends required by
applicable state and federal corporate and securities laws):

                  (i)  THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                       REGISTERED UNDER THE SECURITIES ACT OF 1933, AND HAVE
                       BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR
                       IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO
                       SUCH SALE OR DISTRIBUTION MAY BE EFFECTED WITHOUT AN
                       EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN
                       OPINION OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY
                       THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE
                       SECURITIES ACT OF 1933.

                  (ii) THE SHARES REPRESENTED BY THIS CERTIFICATE MAY BE
                       TRANSFERRED ONLY IN ACCORDANCE WITH THE TERMS OF AN
                       AGREEMENT BETWEEN THE COMPANY AND THE SHAREHOLDER, A COPY



                                     - 6 -
<PAGE>   29

                       OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY.

             (b) STOP-TRANSFER NOTICES. Purchaser agrees that, in order to
ensure compliance with the restrictions referred to herein, the Company may
issue appropriate "stop transfer" instructions to its transfer agent, if any,
and that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

             (c) REFUSAL TO TRANSFER. The Company shall not be required (i) to
transfer on its books any Shares that have been sold or otherwise transferred in
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

             (d) REMOVAL OF LEGEND. When all of the following events have
occurred, the Shares then held by Purchaser will no longer be subject to the
legend referred to in Section 6(a)(ii): (i) the termination of the Right of
First Refusal; (ii) the expiration or termination of the market standoff
provisions of Section 3(g) (and of any agreement entered pursuant to Section
3(g)); and (iii) the expiration or exercise in full of the Repurchase Option.
After such time, and upon Purchaser's request, a new certificate or certificates
representing the Shares not repurchased shall be issued without the legend
referred to in Section 6(a)(ii), and delivered to Purchaser.

        7. NO EMPLOYMENT RIGHTS. Nothing in this Agreement shall affect in any
manner whatsoever the right or power of the Company, or a Parent or Subsidiary
of the Company, to terminate Purchaser's employment or consulting relationship,
for any reason, with or without cause.

        8. SECTION 83(b) ELECTION. Purchaser understands that Section 83(a) of
the Internal Revenue Code of 1986, as amended (the "Code"), taxes as ordinary
income for a Nonstatutory Stock Option and as alternative minimum taxable income
for an Incentive Stock Option the difference between the amount paid for the
Shares and the Fair Market Value of the Shares as of the date any restrictions
on the Shares lapse. In this context, "restriction" means the right of the
Company to buy back the Shares pursuant to the Repurchase Option set forth in
Section 3(a) of this Agreement. Purchaser understands that Purchaser may elect
to be taxed at the time the Shares are purchased, rather than when and as the
Repurchase Option expires, by filing an election under Section 83(b) (an "83(b)
Election") of the Code with the Internal Revenue Service within 30 days from the
date of purchase. Even if the Fair Market Value of the Shares at the time of the
execution of this Agreement equals the amount paid for the Shares, the election
must be made to avoid income and alternative minimum tax treatment under Section
83(a) in the future. Purchaser understands that failure to file such an election
in a timely manner may result in adverse tax consequences for Purchaser.
Purchaser further understands that an additional copy of such election form
should be filed with his or her federal income tax return for the calendar year
in which the date of this Agreement falls. Purchaser acknowledges that the
foregoing is only a summary of the effect of United States federal income
taxation with respect to purchase of the Shares hereunder, and does not purport
to be complete. Purchaser further acknowledges that the Company has directed
Purchaser to seek independent advice regarding the applicable


                                     - 7 -
<PAGE>   30

provisions of the Code, the income tax laws of any municipality, state or
foreign country in which Purchaser may reside, and the tax consequences of
Purchaser's death.

        Purchaser agrees that he or she will execute and deliver to the Company
with this executed Agreement a copy of the Acknowledgment and Statement of
Decision Regarding Section 83(b) Election (the "Acknowledgment") attached hereto
as Attachment B. Purchaser further agrees that he or she will execute and submit
with the Acknowledgment a copy of the 83(b) Election attached hereto as
Attachment C (for tax purposes in connection with the early exercise of an
option) if Purchaser has indicated in the Acknowledgment his or her decision to
make such an election.

        9. MISCELLANEOUS.

             (a) GOVERNING LAW. This Agreement and all acts and transactions
pursuant hereto and the rights and obligations of the parties hereto shall be
governed, construed and interpreted in accordance with the laws of the State of
California, without giving effect to principles of conflicts of law.

             (b) ENTIRE AGREEMENT; ENFORCEMENT OF RIGHTS. This Agreement sets
forth the entire agreement and understanding of the parties relating to the
subject matter herein and merges all prior discussions between them. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, shall be effective unless in writing signed by the parties
to this Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

             (c) SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith. In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (i) such
provision shall be excluded from this Agreement, (ii) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (iii)
the balance of the Agreement shall be enforceable in accordance with its terms.

             (d) CONSTRUCTION. This Agreement is the result of negotiations
between and has been reviewed by each of the parties hereto and their respective
counsel, if any; accordingly, this Agreement shall be deemed to be the product
of all of the parties hereto, and no ambiguity shall be construed in favor of or
against any one of the parties hereto.

             (e) NOTICES. Any notice required or permitted by this Agreement
shall be in writing and shall be deemed sufficient when delivered personally or
sent by telegram or fax or 48 hours after being deposited in the U.S. mail, as
certified or registered mail, with postage prepaid, and addressed to the party
to be notified at such party's address as set forth below or as subsequently
modified by written notice.

             (f) COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.



                                     - 8 -
<PAGE>   31

             (g) SUCCESSORS AND ASSIGNS. The rights and benefits of this
Agreement shall inure to the benefit of, and be enforceable by the Company's
successors and assigns. The rights and obligations of Purchaser under this
Agreement may only be assigned with the prior written consent of the Company.

             (h) CALIFORNIA CORPORATE SECURITIES LAW. THE SALE OF THE SECURITIES
WHICH ARE THE SUBJECT OF THIS AGREEMENT HAS NOT BEEN QUALIFIED WITH THE
COMMISSIONER OF CORPORATIONS OF THE STATE OF CALIFORNIA AND THE ISSUANCE OF THE
SECURITIES OR THE PAYMENT OR RECEIPT OF ANY PART OF THE CONSIDERATION THEREFOR
PRIOR TO THE QUALIFICATION IS UNLAWFUL, UNLESS THE SALE OF SECURITIES IS EXEMPT
FROM QUALIFICATION BY SECTION 25100, 25102 OR 25105 OF THE CALIFORNIA
CORPORATIONS CODE. THE RIGHTS OF ALL PARTIES TO THIS AGREEMENT ARE EXPRESSLY
CONDITIONED UPON THE QUALIFICATION BEING OBTAINED, UNLESS THE SALE IS SO EXEMPT.





                            [Signature Page Follows]



                                     - 9 -
<PAGE>   32

        The parties have executed this Agreement as of the date first set forth
above.

                                       COMPANY:


                                       PDF SOLUTIONS, Inc.

                                       By:
                                          -------------------------------------

                                       Name:
                                            -----------------------------------
                                            (print)

                                       Title:
                                             ----------------------------------

                                       PURCHASER:

                                       <<Optionee>>

                                        ---------------------------------------
                                       (Signature)

                                        ---------------------------------------
                                       (Print Name)

                                       Address:
                                               --------------------------------

                                               --------------------------------


I, ______________________, spouse of <<Optionee>>, have read and hereby approve
the foregoing Agreement. In consideration of the Company's granting my spouse
the right to purchase the Shares as set forth in the Agreement, I hereby agree
to be bound irrevocably by the Agreement and further agree that any community
property or similar interest that I may have in the Shares shall hereby be
similarly bound by the Agreement. I hereby appoint my spouse as my
attorney-in-fact with respect to any amendment or exercise of any rights under
the Agreement.


                                       ------------------------------------
                                       Spouse of <<Optionee>>



                                     - 10 -
<PAGE>   33

                                  ATTACHMENT A

                      ASSIGNMENT SEPARATE FROM CERTIFICATE



             FOR VALUE RECEIVED and pursuant to that certain Early Exercise
Notice and Restricted Stock Purchase Agreement between the undersigned
("Purchaser") and PDF Solutions, Inc. (the "Company") dated _______________,
____ (the "Agreement"), Purchaser hereby sells, assigns and transfers unto the
Company _________________________________ (________) shares of the Common Stock
of the Company, standing in Purchaser's name on the books of the Company and
represented by Certificate No. ____, and does hereby irrevocably constitute and
appoint ________________________________________________ to transfer said stock
on the books of the Company with full power of substitution in the premises.
THIS ASSIGNMENT MAY ONLY BE USED AS AUTHORIZED BY THE AGREEMENT AND THE
ATTACHMENTS THERETO.

Dated: ____________, 20__.

                                       Signature:

                                       ------------------------------------
                                       <<Optionee>>

                                       ------------------------------------
                                       Spouse of <<Optionee>> (if applicable)



Instruction: Please do not fill in any blanks other than the signature line. The
purpose of this assignment is to enable the Company to exercise its Repurchase
Option set forth in the Agreement without requiring additional signatures on the
part of Purchaser.


<PAGE>   34

                                  ATTACHMENT B


                    ACKNOWLEDGMENT AND STATEMENT OF DECISION
                        REGARDING SECTION 83(b) ELECTION


        The undersigned (which term includes the undersigned's spouse), a
purchaser of ___________ shares of Common Stock of PDF Solutions, Inc., a
California corporation (the "Company") by exercise of an option (the "Option")
granted pursuant to the Company's 1997 Stock Plan (the "Plan"), hereby states as
follows:

        1. The undersigned acknowledges receipt of a copy of the Plan relating
to the offering of such shares. The undersigned has carefully reviewed the Plan
and the option agreement pursuant to which the Option was granted.

        2. The undersigned either [check and complete as applicable]:

              (a)____ has consulted, and has been fully advised by, the
                     undersigned's own tax advisor,  _________________________,
                     whose business address is ______________________________,
                     regarding the federal, state and local tax consequences of
                     purchasing shares under the Plan, and particularly
                     regarding the advisability of making elections pursuant to
                     Section 83(b) of the Internal Revenue Code of 1986, as
                     amended (the "Code") and pursuant to the corresponding
                     provisions, if any, of applicable state law; or

              (b)____ has knowingly chosen not to consult such a tax advisor.

             3. The undersigned hereby states that the undersigned has decided
[check as applicable]:

              (a)____ to make an election pursuant to Section 83(b) of the
                     Code, and is submitting to the Company, together with the
                     undersigned's executed Early Exercise Notice and Restricted
                     Stock Purchase Agreement, an executed form entitled
                     "Election Under Section 83(b) of the Internal Revenue Code
                     of 1986;" or

              (b)____ not to make an election pursuant to Section 83(b) of
                     the Code.
<PAGE>   35

        4. Neither the Company nor any subsidiary or representative of the
Company has made any warranty or representation to the undersigned with respect
to the tax consequences of the undersigned's purchase of shares under the Plan
or of the making or failure to make an election pursuant to Section 83(b) of the
Code or the corresponding provisions, if any, of applicable state law.

Date:
-----------------------------------          -----------------------------------
                                             <<Optionee>>


Date:
-----------------------------------          -----------------------------------
                                             Spouse of <<Optionee>>



                                     - 2 -
<PAGE>   36

                                  ATTACHMENT C

                          ELECTION UNDER SECTION 83(b)
                      OF THE INTERNAL REVENUE CODE OF 1986

        The undersigned taxpayer hereby elects, pursuant to Section 83(b) of the
Internal Revenue Code, to include in taxpayer's gross income or alternative
minimum taxable income, as applicable, for the current taxable year, the amount
of any income that may be taxable to taxpayer in connection with taxpayer's
receipt of the property described below:

1.      The name, address, taxpayer identification number and taxable year of
        the undersigned are as follows:

        NAME OF TAXPAYER:  <<Optionee>>

        NAME OF SPOUSE:
                           -----------------------------------
        ADDRESS:
                           -------------------------------------------------

                           -------------------------------------------------

        IDENTIFICATION NO. OF TAXPAYER:
                                       ----------------

        IDENTIFICATION NO. OF SPOUSE:
                                       ----------------

        TAXABLE YEAR:
                                       ----------------

2.      The property with respect to which the election is made is described as
        follows:

        ______________ shares of the Common Stock of PDF Solutions, Inc., a
        California corporation (the "Company").

3.      The date on which the property was transferred is:
                                                          --------------

4.      The property is subject to the following restrictions:

        Repurchase option at cost in favor of the Company upon termination of
        taxpayer's employment or consulting relationship.

5.      The fair market value at the time of transfer, determined without regard
        to any restriction other than a restriction which by its terms will
        never lapse, of such property is: $
                                           --------------

6.      The amount (if any) paid for such property: $
                                                     ---------------

The undersigned has submitted a copy of this statement to the person for whom
the services were performed in connection with the undersigned's receipt of the
above-described property. The transferee of such property is the person
performing the services in connection with the transfer of said property.

The undersigned understands that the foregoing election may not be revoked
except with the consent of the Commissioner.

Date:
-----------------------------------          -----------------------------------
                                             <<Optionee>>


Date:
-----------------------------------          -----------------------------------
                                             Spouse of <<Optionee>>



<PAGE>   37

                               RECEIPT AND CONSENT


        The undersigned hereby acknowledges receipt of a photocopy of
Certificate No. ______ for ________ shares of Common Stock of PDF Solutions,
Inc. (the "Company").

        The undersigned further acknowledges that the Secretary of the Company,
or his or her designee, is acting as escrow holder pursuant to the Early
Exercise Notice and Restricted Stock Purchase Agreement Purchaser has previously
entered into with the Company. As escrow holder, the Secretary of the Company,
or his or her designee, holds the original of the aforementioned certificate
issued in the undersigned's name.

Date:
-----------------------------------          -----------------------------------
                                             <<Optionee>>


<PAGE>   38

                                    EXHIBIT B

                               PDF SOLUTIONS, INC.

                                 1997 STOCK PLAN

             EXERCISE NOTICE AND RESTRICTED STOCK PURCHASE AGREEMENT

        This Agreement ("Agreement") is made as of ______________, by and
between PDF Solutions, Inc., a California corporation (the "Company"), and
<<Optionee>> ("Purchaser"). To the extent any capitalized terms used in this
Agreement are not defined, they shall have the meaning ascribed to them in the
1997 Stock Plan.

        1. EXERCISE OF OPTION. Subject to the terms and conditions hereof,
Purchaser hereby elects to exercise his or her option to purchase ______________
shares of the Common Stock (the "Shares") of the Company under and pursuant to
the Company's 1997 Stock Plan (the "Plan") and the Stock Option Agreement dated
______________ (the "Option Agreement"). The purchase price for the Shares shall
be $<<ExercisePrice>> per Share for a total purchase price of $_______________.
The term "Shares" refers to the purchased Shares and all securities received in
replacement of the Shares or as stock dividends or splits, all securities
received in replacement of the Shares in a recapitalization, merger,
reorganization, exchange or the like, and all new, substituted or additional
securities or other properties to which Purchaser is entitled by reason of
Purchaser's ownership of the Shares.

        2. TIME AND PLACE OF EXERCISE. The purchase and sale of the Shares under
this Agreement shall occur at the principal office of the Company simultaneously
with the execution and delivery of this Agreement in accordance with the
provisions of Section 2(b) of the Option Agreement. On such date, the Company
will deliver to Purchaser a certificate representing the Shares to be purchased
by Purchaser (which shall be issued in Purchaser's name) against payment of the
purchase price therefor by Purchaser by (a) check made payable to the Company,
(b) cancellation of indebtedness of the Company to Purchaser, (c) delivery of
shares of the Common Stock of the Company in accordance with Section 3 of the
Option Agreement, (d) delivery of a promissory note in the form attached as
Exhibit C to the Option Agreement (or in any form acceptable to the Company), or
(e) a combination of the foregoing. If Purchaser delivers a promissory note as
partial or full payment of the purchase price, Purchaser will also deliver a
Pledge and Security Agreement in the form attached as Exhibit D to the Option
Agreement (or in any form acceptable to the Company).

        3. LIMITATIONS ON TRANSFER. In addition to any other limitation on
transfer created by applicable securities laws, Purchaser shall not assign,
encumber or dispose of any interest in the Shares except in compliance with the
provisions below and applicable securities laws.



                                     - 2 -
<PAGE>   39

             (a) RIGHT OF FIRST REFUSAL. Before any Shares held by Purchaser or
any transferee of Purchaser (either being sometimes referred to herein as the
"Holder") may be sold or otherwise transferred (including transfer by gift or
operation of law), the Company or its assignee(s) shall have a right of first
refusal to purchase the Shares on the terms and conditions set forth in this
Section 3(a) (the "Right of First Refusal").

                    (i) NOTICE OF PROPOSED TRANSFER. The Holder of the Shares
shall deliver to the Company a written notice (the "Notice") stating: (i) the
Holder's bona fide intention to sell or otherwise transfer such Shares; (ii) the
name of each proposed purchaser or other transferee ("Proposed Transferee");
(iii) the number of Shares to be transferred to each Proposed Transferee; and
(iv) the terms and conditions of each proposed sale or transfer. The Holder
shall offer the Shares at the same price (the "Offered Price") and upon the same
terms (or terms as similar as reasonably possible) to the Company or its
assignee(s).

                    (ii) EXERCISE OF RIGHT OF FIRST REFUSAL. At any time within
30 days after receipt of the Notice, the Company and/or its assignee(s) may, by
giving written notice to the Holder, elect to purchase all, but not less than
all, of the Shares proposed to be transferred to any one or more of the Proposed
Transferees, at the purchase price determined in accordance with subsection
(iii) below.

                    (iii) PURCHASE PRICE. The purchase price ("Purchase Price")
for the Shares purchased by the Company or its assignee(s) under this Section
3(b) shall be the Offered Price. If the Offered Price includes consideration
other than cash, the cash equivalent value of the non-cash consideration shall
be determined by the Board of Directors of the Company in good faith.

                    (iv) PAYMENT. Payment of the Purchase Price shall be made,
at the option of the Company or its assignee(s), in cash (by check), by
cancellation of all or a portion of any outstanding indebtedness of the Holder
to the Company (or, in the case of repurchase by an assignee, to the assignee),
or by any combination thereof within 30 days after receipt of the Notice or in
the manner and at the times set forth in the Notice.

                    (v) HOLDER'S RIGHT TO TRANSFER. If all of the Shares
proposed in the Notice to be transferred to a given Proposed Transferee are not
purchased by the Company and/or its assignee(s) as provided in this Section
3(b), then the Holder may sell or otherwise transfer such Shares to that
Proposed Transferee at the Offered Price or at a higher price, provided that
such sale or other transfer is consummated within 60 days after the date of the
Notice and provided further that any such sale or other transfer is effected in
accordance with any applicable securities laws and the Proposed Transferee
agrees in writing that the provisions of this Section 3 shall continue to apply
to the Shares in the hands of such Proposed Transferee. If the Shares described
in the Notice are not transferred to the Proposed Transferee within such period,
or if the Holder proposes to change the price or other terms to make them more
favorable to the Proposed Transferee, a new Notice shall be given to the
Company, and the Company and/or its assignees shall again be offered the Right
of First Refusal before any Shares held by the Holder may be sold or otherwise
transferred.



                                     - 3 -
<PAGE>   40

                    (vi) EXCEPTION FOR CERTAIN FAMILY TRANSFERS. Anything to the
contrary contained in this Section 3(b) notwithstanding, the transfer of any or
all of the Shares during Purchaser's lifetime or on Purchaser's death by will or
intestacy to Purchaser's Immediate Family (as defined below) or a trust for the
benefit of Purchaser's Immediate Family shall be exempt from the provisions of
this Section 3(b). "Immediate Family" as used herein shall mean spouse, lineal
descendant or antecedent, father, mother, brother or sister. In such case, the
transferee or other recipient shall receive and hold the Shares so transferred
subject to the provisions of this Section, and there shall be no further
transfer of such Shares except in accordance with the terms of this Section 3.

             (b) INVOLUNTARY TRANSFER.

                    (i) COMPANY'S RIGHT TO PURCHASE UPON INVOLUNTARY TRANSFER.
In the event, at any time after the date of this Agreement, of any transfer by
operation of law or other involuntary transfer (including divorce or death, but
excluding, in the event of death, a transfer to Immediate Family as set forth in
Section 3(b)(vi) above) of all or a portion of the Shares by the record holder
thereof, the Company shall have the right to purchase all of the Shares
transferred at the greater of the purchase price paid by Purchaser pursuant to
this Agreement or the Fair Market Value of the Shares on the date of transfer.
Upon such a transfer, the person acquiring the Shares shall promptly notify the
Secretary of the Company of such transfer. The right to purchase such Shares
shall be provided to the Company for a period of 30 days following receipt by
the Company of written notice by the person acquiring the Shares.

                    (ii) PRICE FOR INVOLUNTARY TRANSFER. With respect to any
stock to be transferred pursuant to Section 3(c)(i), the price per Share shall
be a price set by the Board of Directors of the Company that will reflect the
current value of the stock in terms of present earnings and future prospects of
the Company. The Company shall notify Purchaser or his or her executor of the
price so determined within 30 days after receipt by it of written notice of the
transfer or proposed transfer of Shares. However, if the Purchaser does not
agree with the valuation as determined by the Board of Directors of the Company,
the Purchaser shall be entitled to have the valuation determined by an
independent appraiser to be mutually agreed upon by the Company and the
Purchaser and whose fees shall be borne equally by the Company and the
Purchaser.

             (c) ASSIGNMENT. The right of the Company to purchase any part of
the Shares may be assigned in whole or in part to any shareholder or
shareholders of the Company or other persons or organizations; provided,
however, that an assignee, other than a corporation that is the parent or a 100%
owned subsidiary of the Company, must pay the Company, upon assignment of such
right, cash equal to the difference between the original purchase price and fair
market value, if the original purchase price is less than the fair market value
of the Shares subject to the assignment.

             (d) RESTRICTIONS BINDING ON TRANSFEREES. All transferees of Shares
or any interest therein will receive and hold such Shares or interest subject to
the provisions of this Agreement, including, insofar as applicable, the
Repurchase Option. Any sale or transfer of the Shares shall be void unless the
provisions of this Agreement are satisfied.



                                     - 4 -
<PAGE>   41

             (e) TERMINATION OF RIGHTS. The Right of First Refusal granted the
Company by Section 3(a) above and the option to repurchase the Shares in the
event of an involuntary transfer granted the Company by Section 3(b) above shall
terminate upon the first sale of Common Stock of the Company to the general
public pursuant to a registration statement filed with and declared effective by
the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Securities Act"). Upon termination of the Right of First Refusal
described in Section 3(a) above, a new certificate or certificates representing
the Shares not repurchased shall be issued, on request, without the legend
referred to in Section 6(a)(ii) herein and delivered to Purchaser.

        4. INVESTMENT AND TAXATION REPRESENTATIONS. In connection with the
purchase of the Shares, Purchaser represents to the Company the following:

             (a) Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the Shares. Purchaser is
purchasing the Shares for investment for his or her own account only and not
with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the Securities Act.

             (b) Purchaser understands that the Shares have not been registered
under the Securities Act by reason of a specific exemption therefrom, which
exemption depends upon, among other things, the bona fide nature of Purchaser's
investment intent as expressed herein.

             (c) Purchaser understands that the Shares are "restricted
securities" under applicable U.S. federal and state securities laws and that,
pursuant to these laws, Purchaser must hold the Shares indefinitely unless they
are registered with the Securities and Exchange Commission and qualified by
state authorities, or an exemption from such registration and qualification
requirements is available. Purchaser acknowledges that the Company has no
obligation to register or qualify the Shares for resale. Purchaser further
acknowledges that if an exemption from registration or qualification is
available, it may be conditioned on various requirements including, but not
limited to, the time and manner of sale, the holding period for the Shares, and
requirements relating to the Company which are outside of the Purchaser's
control, and which the Company is under no obligation and may not be able to
satisfy.

             (d) Purchaser understands that Purchaser may suffer adverse tax
consequences as a result of Purchaser's purchase or disposition of the Shares.
Purchaser represents that Purchaser has consulted any tax consultants Purchaser
deems advisable in connection with the purchase or disposition of the Shares and
that Purchaser is not relying on the Company for any tax advice.

        5 RESTRICTIVE LEGENDS AND STOP-TRANSFER ORDERS.

             (a) LEGENDS. The certificate or certificates representing the
Shares shall bear the following legends (as well as any legends required by
applicable state and federal corporate and securities laws):

                  (i)   THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                        REGISTERED UNDER THE


                                     - 5 -
<PAGE>   42

                        SECURITIES ACT OF 1933, AND HAVE BEEN ACQUIRED FOR
                        INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION
                        WITH, THE SALE OR DISTRIBUTION THEREOF. NO SUCH SALE OR
                        DISTRIBUTION MAY BE EFFECTED WITHOUT AN EFFECTIVE
                        REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF
                        COUNSEL IN A FORM SATISFACTORY TO THE COMPANY THAT SUCH
                        REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OF
                        1933.

                  (ii)  THE SHARES REPRESENTED BY THIS CERTIFICATE MAY BE
                        TRANSFERRED ONLY IN ACCORDANCE WITH THE TERMS OF AN
                        AGREEMENT BETWEEN THE COMPANY AND THE STOCKHOLDER, A
                        COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE
                        COMPANY.

             (b) STOP-TRANSFER NOTICES. Purchaser agrees that, in order to
ensure compliance with the restrictions referred to herein, the Company may
issue appropriate "stop transfer" instructions to its transfer agent, if any,
and that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

             (c) REFUSAL TO TRANSFER. The Company shall not be required (i) to
transfer on its books any Shares that have been sold or otherwise transferred in
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

        6. NO EMPLOYMENT RIGHTS. Nothing in this Agreement shall affect in any
manner whatsoever the right or power of the Company, or a Parent or Subsidiary
of the Company, to terminate Purchaser's employment or consulting relationship,
for any reason, with or without cause.

        7. MARKET STANDOFF AGREEMENT. In connection with the initial public
offering of the Company's securities and upon request of the Company or the
underwriters managing such underwritten offering of the Company's securities,
Purchaser agrees not to sell, make any short sale of, loan, grant any option for
the purchase of, or otherwise dispose of any securities of the Company (other
than those included in the registration) without the prior written consent of
the Company or such underwriters, as the case may be, for such period of time
(not to exceed 180 days) from the effective date of such registration as may be
requested by the Company or such managing underwriters and to execute an
agreement reflecting the foregoing as may be requested by the underwriters at
the time of the Company's initial public offering.



                                     - 6 -
<PAGE>   43

        8. MISCELLANEOUS.

             (a) GOVERNING LAW. This Agreement and all acts and transactions
pursuant hereto and the rights and obligations of the parties hereto shall be
governed, construed and interpreted in accordance with the laws of the State of
California, without giving effect to principles of conflicts of law.

             (b) ENTIRE AGREEMENT; ENFORCEMENT OF RIGHTS. This Agreement sets
forth the entire agreement and understanding of the parties relating to the
subject matter herein and merges all prior discussions between them. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, shall be effective unless in writing signed by the parties
to this Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

             (c) SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith. In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (i) such
provision shall be excluded from this Agreement, (ii) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (iii)
the balance of the Agreement shall be enforceable in accordance with its terms.

             (d) CONSTRUCTION. This Agreement is the result of negotiations
between and has been reviewed by each of the parties hereto and their respective
counsel, if any; accordingly, this Agreement shall be deemed to be the product
of all of the parties hereto, and no ambiguity shall be construed in favor of or
against any one of the parties hereto.

             (e) NOTICES. Any notice required or permitted by this Agreement
shall be in writing and shall be deemed sufficient when delivered personally or
sent by telegram or fax or 48 hours after being deposited in the U.S. mail, as
certified or registered mail, with postage prepaid, and addressed to the party
to be notified at such party's address as set forth below or as subsequently
modified by written notice.

             (f) COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

             (g) SUCCESSORS AND ASSIGNS. The rights and benefits of this
Agreement shall inure to the benefit of, and be enforceable by the Company's
successors and assigns. The rights and obligations of Purchaser under this
Agreement may only be assigned with the prior written consent of the Company.



                                     - 7 -
<PAGE>   44

        The parties have executed this Agreement as of the date first set forth
above.

                                       COMPANY:


                                       PDF SOLUTIONS, INC.

                                       By:
                                          -------------------------------------

                                       Name:
                                            -----------------------------------
                                            (print)

                                       Title:
                                             ----------------------------------

                                       Address:
                                               --------------------------------

                                               --------------------------------

                                       PURCHASER:

                                       <<Optionee>>

                                        ---------------------------------------
                                       (Signature)

                                        ---------------------------------------
                                       (Print Name)

                                       Address:
                                               --------------------------------

                                               --------------------------------

I, ______________________, spouse of <<Optionee>>, have read and hereby approve
the foregoing Agreement. In consideration of the Company's granting my spouse
the right to purchase the Shares as set forth in the Agreement, I hereby agree
to be bound irrevocably by the Agreement and further agree that any community
property or similar interest that I may have in the Shares shall hereby be
similarly bound by the Agreement. I hereby appoint my spouse as my
attorney-in-fact with respect to any amendment or exercise of any rights under
the Agreement.


                                       ------------------------------------
                                       Spouse of <<Optionee>>



                                     - 8 -
<PAGE>   45

                                    EXHIBIT C

                                 PROMISSORY NOTE


$__________                                                 San Jose, California
                                                           _______________, 2000


        For value received, the undersigned promises to pay PDF Solutions, Inc.,
a California corporation (the "Company"), at its principal office the principal
sum of $__________ with interest from the date hereof at a rate of _____% per
annum, compounded annually, on the unpaid balance of such principal sum. Such
accrued interest shall be due and payable on each annual interest compounding
date, and such principal shall be due and payable on ______________________.

        If the undersigned's employment or consulting relationship with the
Company is terminated prior to payment in full of this Note, this Note shall be
immediately due and payable.

        Principal and interest are payable in lawful money of the United States
of America. AMOUNTS DUE UNDER THIS NOTE MAY BE PREPAID AT ANY TIME WITHOUT
INTEREST OR PENALTY.

        Should suit be commenced to collect any sums due under this Note, such
sum as the Court may deem reasonable shall be added hereto as attorneys' fees.
The makers and endorsers have severally waived presentment for payment, protest,
notice of protest and notice of nonpayment of this Note.

        This Note, which is full recourse, is secured by a pledge of certain
shares of Common Stock of the Company and is subject to the terms of a Pledge
and Security Agreement between the undersigned and the Company of even date
herewith.


                                       ____________________________________
                                       <<Optionee>>


<PAGE>   46

                                    EXHIBIT D

                          PLEDGE AND SECURITY AGREEMENT


        This Pledge and Security Agreement (the "Agreement") is entered into
this _____ day of ____________ by and between PDF Solutions, Inc., a California
corporation (the "Company") and <<Optionee>> ("Purchaser").

                                    RECITALS

        In connection with Purchaser's exercise of an option to purchase certain
shares of the Company's Common Stock (the "Shares") pursuant to an Option
Agreement dated __________ between Purchaser and the Company, Purchaser is
delivering a promissory note of even date herewith (the "Note") in full or
partial payment of the exercise price for the Shares. The company requires that
the Note be secured by a pledge of the Shares or the terms set forth below.

                                    AGREEMENT

        In consideration of the Company's acceptance of the Note as full or
partial payment of the exercise price of the Shares, and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the parties
hereto agree as follows:

        1. The Note shall become payable in full upon the voluntary or
involuntary termination or cessation of employment of Purchaser with the
Company, for any reason, with or without cause (including death or disability).

        2. Purchaser shall deliver to the Secretary of the Company, or his or
her designee (hereinafter referred to as the "Pledge Holder"), all certificates
representing the Shares, together with an Assignment Separate from Certificate
in the form attached to this Agreement as Attachment A executed by Purchaser and
by Purchaser's spouse (if required for transfer), in blank, for use in
transferring all or a portion of the Shares to the Company if, as and when
required pursuant to this Agreement. In addition, if Purchaser is married,
Purchaser's spouse shall execute the signature page attached to this Agreement.

        3. As security for the payment of the Note and any renewal, extension or
modification of the Note, Purchaser hereby grants to the Company a security
interest in and pledges with and delivers to the Company Purchaser's Shares
(sometimes referred to herein as the "Collateral").

        4. In the event that Purchaser prepays all or a portion of the Note, in
accordance with the provisions thereof, Purchaser intends, unless written notice
to the contrary is delivered to the Pledge Holder, that the Shares represented
by the portion of the Note so repaid, including annual interest thereon, shall
continue to be so held by the Pledge Holder, to serve as independent collateral
for the outstanding portion of the Note for the purpose of commencing the
holding period set forth in Rule 144(d) promulgated under the Securities Act of
1933, as amended (the "Securities Act").


<PAGE>   47

        5. In the event of any foreclosure of the security interest created by
this Agreement, the Company may sell the Shares at a private sale or may
repurchase the Shares itself. The parties agree that, prior to the establishment
of a public market for the Shares of the Company, the securities laws affecting
sale of the Shares make a public sale of the Shares commercially unreasonable.
The parties further agree that the repurchasing of such Shares by the Company,
or by any person to whom the Company may have assigned its rights under this
Agreement, is commercially reasonable if made at a price determined by the Board
of Directors in its discretion, fairly exercised, representing what would be the
fair market value of the Shares reduced by any limitation on transferability,
whether due to the size of the block of shares or the restrictions of applicable
securities laws.

        6. In the event of default in payment when due of any indebtedness under
the Note, the Company may elect then, or at any time thereafter, to exercise all
rights available to a secured party under the California Commercial Code
including the right to sell the Collateral at a private or public sale or
repurchase the Shares as provided above. The proceeds of any sale shall be
applied in the following order:

             (a) To the extent necessary, proceeds shall be used to pay all
reasonable expenses of the Company in enforcing this Agreement and the Note,
including, without limitation, reasonable attorney's fees and legal expenses
incurred by the Company.

             (b) To the extent necessary, proceeds shall be used to satisfy any
remaining indebtedness under Purchaser's Note.

             (c) Any remaining proceeds shall be delivered to Purchaser.

        7. Upon full payment by Purchaser of all amounts due under the Note,
Pledge Holder shall deliver to Purchaser all Shares in Pledge Holder's
possession belonging to Purchaser, and Pledge Holder shall thereupon be
discharged of all further obligations under this Agreement; provided, however,
that Pledge Holder shall nevertheless retain the Shares as escrow agent if at
the time of full payment by Purchaser said Shares are still subject to a
Repurchase Option in favor of the Company.



                                     - 2 -
<PAGE>   48

        The parties have executed this Pledge and Security Agreement as of the
date first set forth above.

                                       COMPANY:


                                       PDF SOLUTIONS, Inc.

                                       By:
                                          -------------------------------------

                                       Name:
                                            -----------------------------------
                                            (print)

                                       Title:
                                             ----------------------------------

                                       PURCHASER:

                                       <<Optionee>>

                                        ---------------------------------------
                                       (Signature)

                                        ---------------------------------------
                                       (Print Name)

                                       Address:
                                               --------------------------------

                                               --------------------------------



                                     - 3 -
<PAGE>   49

                                  ATTACHMENT A

                      ASSIGNMENT SEPARATE FROM CERTIFICATE

             FOR VALUE RECEIVED and pursuant to that certain Pledge and Security
Agreement between the undersigned ("Purchaser") and PDF Solutions, Inc., dated
_____________, (the "Agreement"), Purchaser hereby sells, assigns and transfers
unto _______________________________ (________) shares of the Common Stock of
PDF Solutions, Inc., standing in Purchaser's name on the books of said
corporation represented by Certificate No. ___ herewith and hereby irrevocably
appoints _____________________________ to transfer said stock on the books of
the within-named corporation with full power of substitution in the premises.
THIS ASSIGNMENT MAY ONLY BE USED AS AUTHORIZED BY THE AGREEMENT.

Dated: ____________

                                       Signature:

                                       ______________________________________
                                       <<Optionee>>

                                       ______________________________________
                                       Spouse of <<Optionee>> (if applicable)



Instruction: Please do not fill in any blanks other than the signature line. The
purpose of this assignment is to perfect the security interest of the Company
pursuant to the Agreement.



                                     - 5 -
<PAGE>   50

                                     RECEIPT


        The undersigned hereby acknowledges receipt of Certificate No. _____ for
__________ shares of Common Stock of PDF Solutions, Inc.


Dated:  _______________


                                       ____________________________________
                                       <<Optionee>>


<PAGE>   51

                               RECEIPT AND CONSENT

        The undersigned hereby acknowledges receipt of a photocopy Certificate
No. _____ purchaser for __________ shares of Common Stock of PDF Solutions, Inc.
(the "Company").

        The undersigned further acknowledges that the Secretary of the Company,
or his or her designee, is acting as Pledge Holder pursuant to the Pledge and
Security Agreement Purchaser has previously entered into with the Company. As
Pledge Holder, the Secretary of the Company, or his or her designee, holds the
original of the aforementioned certificate issued in the undersigned's name.


Dated:  _______________


                                       ____________________________________
                                       <<Optionee>>


<PAGE>   52

                                     RECEIPT


        PDF Solutions, Inc. (the "Company") hereby acknowledges receipt of a
check in the amount of $____________ given by <<Optionee>> as consideration for
Certificate No. _________ for __________ shares of Common Stock of PDF
Solutions, Inc.


Dated:  ____________                   PDF Solutions, Inc.

                                       By:_____________________________________

                                       Name:___________________________________
                                            (print)

                                       Title:__________________________________



                                     - 2 -
<PAGE>   53

                               PDF SOLUTIONS, INC.

                    NOTICE OF GRANT OF STOCK PURCHASE RIGHTS



<<Optionee>>


        You have been granted an option to purchase Common Stock ("Common
Stock") of PDF Solutions, Inc. (the "Company") as follows:

        Board Approval Date:                <<BoardApprovDate>>

        Vesting Commencement Date:          <<VestingCommenceDate>>

        Exercise Price Per Share:           $<<ExercisePrice>>

        Total No. Purchase Rights Granted:  <<NoofShares>>

        Total Purchase Price:               $<<TotalExercisePrice>>

        Vesting Schedule:                   <<Vesting>>

        Termination Period:                 This Option may be exercised for 60
                                            days after termination of employment
                                            or consulting relationship.


<PAGE>   54

        By your signature and the signature of the Company's representative
below, you and the Company agree that this option is granted under and governed
by the terms and conditions of the Restricted Stock Purchase Agreement, which is
attached and made a part of this document.



<<OPTIONEE>>:                          PDF SOLUTIONS, INC.:


                                       By:
-----------------------------------       -----------------------------------
Signature

                                          P. S. Melman, CFO
-----------------------------------       -----------------------------------
Print Name                                Print Name and Title

-----------------------------------
Address

-----------------------------------
Address



                                     - 4 -
<PAGE>   55
                              PDF SOLUTIONS, INC.
                      RESTRICTED STOCK PURCHASE AGREEMENT
                                1997 STOCK PLAN

        This Restricted Stock Purchase Agreement (the "Agreement") is made as of
__________, 2000 by and between PDF Solutions, Inc., a California corporation
(the "Company"), and <<Optionee>> ("Purchaser") pursuant to the Company's 1997
Stock Plan. To the extent any capitalized terms used in this Agreement are not
defined, they shall have the meaning ascribed to them in the 1997 Stock Plan.

        1. SALE OF STOCK. Subject to the terms and conditions of this Agreement,
on the Purchase Date (as defined below) the Company will issue and sell to
Purchaser, and Purchaser agrees to purchase from the Company, <<NoofShares>>
shares of the Company's Common Stock (the "Shares") at a purchase price of
$<<ExercisePrice>> per Share for a total purchase price of
$<<TotalExercisePrice>>. The per share purchase price of the Shares shall be not
less than 85% of the Fair Market Value of the Shares as of the date of offer of
the Shares to Purchaser, or, in the case of any person owning stock representing
more than 10% of the total combined voting power of all classes of stock of the
Company (or any affiliated company), the per share price shall be not less than
100% of the Fair Market Value of the Shares on such date. The term "Shares"
refers to the purchased Shares and all securities received in replacement of or
in connection with the Shares pursuant to stock dividends or splits, all
securities received in replacement of the Shares in a recapitalization, merger,
reorganization, exchange or the like, and all new, substituted or additional
securities or other properties to which Purchaser is entitled by reason of
Purchaser's ownership of the Shares.

        2. PURCHASE. The purchase and sale of the Shares under this Agreement
shall occur at the principal office of the Company simultaneously with the
execution of this Agreement by the parties, or on such other date as the Company
and Purchaser shall agree (the "Purchase Date"). On the Purchase Date, the
Company will deliver to Purchaser a certificate representing the Shares to be
purchased by Purchaser (which shall be issued in Purchaser's name) against
payment of the purchase price therefor by Purchaser by (a) check made payable to
the Company, (b) cancellation of indebtedness of the Company to Purchase, (c)
delivery of a promissory note in the form attached as Exhibit A to this
Agreement (or in any form acceptable to the Company), or (d) by a combination of
the foregoing. If Purchaser delivers a promissory note as partial or full
payment of the purchase price, Purchaser shall also deliver a Pledge and
Security Agreement in the form attached as Exhibit B to this Agreement (or in
any form acceptable to the Company).

        3. LIMITATIONS ON TRANSFER. In addition to any other limitation on
transfer created by applicable securities laws, Purchaser shall not assign,
encumber or dispose of any interest in the Shares while the Shares are subject
to the Company's Repurchase Option (as defined below). After any Shares have
been released from such Repurchase Option, Purchaser shall not assign, encumber
or dispose of any interest in such Shares except in compliance with the
provisions below and applicable securities laws.

             (a) REPURCHASE OPTION.

                    (i) In the event of the voluntary or involuntary termination
of Purchaser's employment or consulting relationship with the Company for any
reason (including death or disability), with or without cause, the Company shall
upon the date of such termination (the "Termination Date") have an irrevocable,
exclusive option (the "Repurchase Option") for a period of 60 days from such
date to repurchase all or any portion of the Shares held by Purchaser as of the
Termination Date which have not yet been released from the Company's Repurchase
Option at the original purchase price per Share specified in Section 1 (adjusted
for any stock splits, stock dividends and the like).


<PAGE>   56

                    (ii) The Repurchase Option shall be exercised by the Company
by written notice to Purchaser or Purchaser's executor and, at the Company's
option, (A) by delivery to Purchaser or Purchaser's executor with such notice of
a check in the amount of the purchase price for the Shares being purchased, or
(B) in the event Purchaser is indebted to the Company, by cancellation by the
Company of an amount of such indebtedness equal to the purchase price for the
Shares being repurchased, or (C) by a combination of (A) and (B) so that the
combined payment and cancellation of indebtedness equals such purchase price.
Upon delivery of such notice and payment of the purchase price in any of the
ways described above, the Company shall become the legal and beneficial owner of
the Shares being repurchased and all rights and interest therein or related
thereto, and the Company shall have the right to transfer to its own name the
number of Shares being repurchased by the Company, without further action by
Purchaser.

                    (iii) One hundred percent (100%) of the Shares shall
initially be subject to the Repurchase Option. The Shares shall begin to be
released from the Repurchase Option on the Vesting Commencement Date. 1/24th of
the total number of Shares shall be released from the Repurchase Option each
month thereafter on the Monthly Vesting Date (as set forth in the signature page
of this Agreement), until all Shares are released from the Repurchase Option.
Fractional shares shall be rounded to the nearest whole share.

             (b) RIGHT OF FIRST REFUSAL. Before any Shares held by Purchaser or
any transferee of Purchaser (either being sometimes referred to herein as the
"Holder") may be sold or otherwise transferred (including transfer by gift or
operation of law), the Company or its assignee(s) shall have a right of first
refusal to purchase the Shares on the terms and conditions set forth in this
Section 3(b) (the "Right of First Refusal").

                    (i) NOTICE OF PROPOSED TRANSFER. The Holder of the Shares
shall deliver to the Company a written notice (the "Notice") stating: (A) the
Holder's bona fide intention to sell or otherwise transfer such Shares; (B) the
name of each proposed purchaser or other transferee ("Proposed Transferee"); (C)
the number of Shares to be transferred to each Proposed Transferee; and (D) the
terms and conditions of each proposed sale or transfer. The Holder shall offer
the Shares at the same price (the "Offered Price") and upon the same terms (or
terms as similar as reasonably possible) to the Company or its assignee(s).

                    (ii) EXERCISE OF RIGHT OF FIRST REFUSAL. At any time within
thirty (30) days after receipt of the Notice, the Company and/or its assignee(s)
may, by giving written notice to the Holder, elect to purchase all, but not less
than all, of the Shares proposed to be transferred to any one or more of the
Proposed Transferees, at the purchase price determined in accordance with
subsection (iii) below.

                    (iii) PURCHASE PRICE. The purchase price ("Purchase Price")
for the Shares purchased by the Company or its assignee(s) under this Section
3(b) shall be the Offered Price. If the Offered Price includes consideration
other than cash, the cash equivalent value of the non-cash consideration shall
be determined by the Board of Directors of the Company in good faith.



                                     - 2 -
<PAGE>   57

                    (iv) PAYMENT. Payment of the Purchase Price shall be made,
at the option of the Company or its assignee(s), in cash (by check), by
cancellation of all or a portion of any outstanding indebtedness of the Holder
to the Company (or, in the case of repurchase by an assignee, to the assignee),
or by any combination thereof within 30 days after receipt of the Notice or in
the manner and at the times set forth in the Notice.

                    (v) HOLDER'S RIGHT TO TRANSFER. If all of the Shares
proposed in the Notice to be transferred to a given Proposed Transferee are not
purchased by the Company and/or its assignee(s) as provided in this Section
3(b), then the Holder may sell or otherwise transfer such Shares to that
Proposed Transferee at the Offered Price or at a higher price, provided that
such sale or other transfer is consummated within 60 days after the date of the
Notice and provided further that any such sale or other transfer is effected in
accordance with any applicable securities laws and the Proposed Transferee
agrees in writing that the provisions of this Section 3 shall continue to apply
to the Shares in the hands of such Proposed Transferee. If the Shares described
in the Notice are not transferred to the Proposed Transferee within such period,
or if the Holder proposes to change the price or other terms to make them more
favorable to the Proposed Transferee, a new Notice shall be given to the
Company, and the Company and/or its assignees shall again be offered the Right
of First Refusal before any Shares held by the Holder may be sold or otherwise
transferred.

                    (vi) EXCEPTION FOR CERTAIN FAMILY TRANSFERS. Anything to the
contrary contained in this Section 3(b) notwithstanding, the transfer of any or
all of the Shares during Purchaser's lifetime or on Purchaser's death by will or
intestacy to Purchaser's Immediate Family or a trust for the benefit of
Purchaser's Immediate Family shall be exempt from the provisions of this Section
3(b). "Immediate Family" as used herein shall mean spouse, lineal descendant or
antecedent, father, mother, brother or sister. In such case, the transferee or
other recipient shall receive and hold the Shares so transferred subject to the
provisions of this Section, and there shall be no further transfer of such
Shares except in accordance with the terms of this Section 3.

             (c) INVOLUNTARY TRANSFER.

                    (i) COMPANY'S RIGHT TO PURCHASE UPON INVOLUNTARY TRANSFER.
In the event, at any time after the date of this Agreement, of any transfer by
operation of law or other involuntary transfer (including death or divorce, but
excluding a transfer to Immediate Family as set forth in Section 3(b)(vi) above)
of all or a portion of the Shares by the record holder thereof, the Company
shall have an option to purchase all of the Shares transferred at the greater of
the purchase price paid by Purchaser pursuant to this Agreement or the Fair
Market Value of the Shares on the date of transfer. Upon such a transfer, the
person acquiring the Shares shall promptly notify the Secretary of the Company
of such transfer. The right to purchase such Shares shall be provided to the
Company for a period of thirty (30) days following receipt by the Company of
written notice by the person acquiring the Shares.

                    (ii) PRICE FOR INVOLUNTARY TRANSFER. With respect to any
stock to be transferred pursuant to Section 3(c)(i), the price per Share shall
be a price set by the Board of Directors of the Company that will reflect the
current value of the stock in terms of present earnings and future prospects of
the Company. The Company shall notify Purchaser or his or her


                                     - 3 -
<PAGE>   58

executor of the price so determined within thirty (30) days after receipt by it
of written notice of the transfer or proposed transfer of Shares. However, if
the Purchaser does not agree with the valuation as determined by the Board of
Directors of the Company, the Purchaser shall be entitled to have the valuation
determined by an independent appraiser to be mutually agreed upon by the Company
and the Purchaser and whose fees shall be borne equally by the Company and the
Purchaser.

             (d) ASSIGNMENT. The right of the Company to purchase any part of
the Shares may be assigned in whole or in part to any stockholder or
stockholders of the Company or other persons or organizations; provided,
however, that an assignee, other than a corporation that is the parent or a 100%
owned subsidiary of the Company, must pay the Company, upon assignment of such
right, cash equal to the difference between the original purchase price and Fair
Market Value, if the original purchase price is less than the Fair Market Value
of the Shares subject to the assignment.

             (e) RESTRICTIONS BINDING ON TRANSFEREES. All transferees of Shares
or any interest therein will receive and hold such Shares or interest subject to
the provisions of this Agreement, including, insofar as applicable, the
Company's option to repurchase under Section 3(a). Any sale or transfer of the
Company's Shares shall be void unless the provisions of this Agreement are met.

             (f) TERMINATION OF RIGHTS. The right of first refusal granted the
Company by Section 3(b) above and the option to repurchase the Shares in the
event of an involuntary transfer granted the Company by Section 3(c) above shall
terminate upon the first sale of Common Stock of the Company to the general
public pursuant to a registration statement filed with and declared effective by
the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Securities Act"). Upon termination of the Right of First Refusal
and the expiration or exercise of the Repurchase Option, a new certificate or
certificates representing the Shares not repurchased shall be issued, on
request, without the legend referred to in Section 6(a)(ii) herein and delivered
to Purchaser.

        4. ESCROW OF UNVESTED SHARES. For purposes of facilitating the
enforcement of the provisions of Section 3 above, Purchaser agrees, immediately
upon receipt of the certificate(s) for the Shares subject to the Company's
Repurchase Option described in Section 3(a), to deliver such certificate(s),
together with an Assignment Separate from Certificate in the form attached to
this Agreement as Exhibit C executed by Purchaser and by Purchaser's spouse (if
required for transfer), in blank, to the Secretary of the Company, or the
Secretary's designee, to hold such certificate(s) and Assignment Separate from
Certificate in escrow and to take all such actions and to effectuate all such
transfers and/or releases as are in accordance with the terms of this Agreement.
Purchaser hereby acknowledges that the Secretary of the Company, or the
Secretary's designee, is so appointed as the escrow holder with the foregoing
authorities as a material inducement to make this Agreement and that said
appointment is coupled with an interest and is accordingly irrevocable.
Purchaser agrees that said escrow holder shall not be liable to any party hereof
(or to any other party). The escrow holder may rely upon any letter, notice or
other document executed by any signature purported to be genuine and may resign
at any time. Purchaser agrees that if the Secretary of the Company, or the
Secretary's designee, resigns as escrow holder for any or no reason, the Board
of Directors of the Company shall have


                                     - 4 -
<PAGE>   59

the power to appoint a successor to serve as escrow holder pursuant to the terms
of this Agreement.

        5. INVESTMENT AND TAXATION REPRESENTATIONS. In connection with the
purchase of the Shares, Purchaser represents to the Company the following:

             (a) Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the securities.
Purchaser is purchasing these securities for investment for his or her own
account only and not with a view to, or for resale in connection with, any
"distribution" thereof within the meaning of the Securities Act.

             (b) Purchaser understands that the securities have not been
registered under the Securities Act by reason of a specific exemption therefrom,
which exemption depends upon, among other things, the bona fide nature of
Purchaser's investment intent as expressed herein.

             (c) Purchaser further acknowledges and understands that the Shares
are "restricted securities" under applicable U.S. federal and state securities
laws and that, pursuant to these laws, Purchaser must hold the Shares
indefinitely unless they are registered with the Securities and Exchange
Commission and qualified by state authorities, or an exemption from such
registration and qualification requirements is available. Purchaser acknowledges
that the Company has no obligation to register or qualify the Shares for resale.
Purchaser further acknowledges that if an exemption from registration or
qualification is available, it may be conditioned on various requirements
including, but not limited to, the time and manner of sale, the holding period
for the Shares, and requirements relating to the Company which are outside of
Purchaser's control, and which the Company is under no obligation and may not be
able to satisfy.

             (d) Purchaser understands that Purchaser may suffer adverse tax
consequences as a result of Purchaser's purchase or disposition of the Shares.
Purchaser represents that Purchaser has consulted any tax consultants Purchaser
deems advisable in connection the purchase or disposition of the Shares and that
Purchaser is not relying on the Company for any tax advice.

        6. RESTRICTIVE LEGENDS AND STOP-TRANSFER ORDERS.

             (a) LEGENDS. The certificate or certificates representing the
Shares shall bear the following legends (as well as any legends required by
applicable state and federal corporate and securities laws):

              (i)    THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
                     UNDER THE SECURITIES ACT OF 1933 (THE "ACT") AND MAY NOT BE
                     OFFERED, SOLD OR OTHERWISE TRANSFERRED, PLEDGED OR
                     HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER THE ACT OR,
                     IN THE OPINION OF COUNSEL IN FORM AND SUBSTANCE
                     SATISFACTORY TO THE ISSUER OF THESE


                                     - 5 -
<PAGE>   60

                     SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE OR
                     HYPOTHECATION IS IN COMPLIANCE THEREWITH.

              (ii)   THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
                     CERTAIN RESTRICTIONS ON TRANSFER AND RIGHT OF FIRST REFUSAL
                     OPTIONS HELD BY THE ISSUER OR ITS ASSIGNEE(S) AS SET FORTH
                     IN THE RESTRICTED STOCK PURCHASE AGREEMENT BETWEEN THE
                     ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF
                     WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE
                     ISSUER. SUCH TRANSFER RESTRICTIONS AND RIGHT OF FIRST
                     REFUSAL ARE BINDING ON TRANSFEREES OF THESE SHARES.

             (b) STOP-TRANSFER NOTICES. Purchaser agrees that, in order to
ensure compliance with the restrictions referred to herein, the Company may
issue appropriate "stop transfer" instructions to its transfer agent, if any,
and that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

             (c) REFUSAL TO TRANSFER. The Company shall not be required (i) to
transfer on its books any Shares that have been sold or otherwise transferred in
violation of any of the provisions of this Agreement or (ii) to treat as owner
of such Shares or to accord the right to vote or pay dividends to any purchaser
or other transferee to whom such Shares shall have been so transferred.

        7. NO EMPLOYMENT RIGHTS. Nothing in this Agreement shall affect in any
manner whatsoever the right or power of the Company, or a parent or subsidiary
of the Company, to terminate Purchaser's employment, for any reason, with or
without cause.

        8. SECTION 83(b) ELECTION. Purchaser understands that Section 83(a) of
the Internal Revenue Code of 1986, as amended (the "Code"), taxes as ordinary
income the difference between the amount paid for the Shares and the Fair Market
Value of the Shares as of the date any restrictions on the Shares lapse. In this
context, "restriction" means the right of the Company to buy back the Shares
pursuant to the Repurchase Option set forth in Section 3(a) of this Agreement.
Purchaser understands that Purchaser may elect to be taxed at the time the
Shares are purchased, rather than when and as the Repurchase Option expires, by
filing an election under Section 83(b) (an "83(b) Election") of the Code with
the Internal Revenue Service within 30 days from the date of purchase. Even if
the Fair Market Value of the Shares at the time of the execution of this
Agreement equals the amount paid for the Shares, the election must be made to
avoid income under Section 83(a) in the future. Purchaser understands that
failure to file such an election in a timely manner may result in adverse tax
consequences for Purchaser. Purchaser further understands that an additional
copy of such election form should be filed with his or her federal income tax
return for the calendar year in which the date of this Agreement falls.
Purchaser acknowledges that the foregoing is only a summary of the effect of
United


                                     - 6 -
<PAGE>   61

States federal income taxation with respect to purchase of the Shares hereunder,
and does not purport to be complete. Purchaser further acknowledges that the
Company has directed Purchaser to seek independent advice regarding the
applicable provisions of the Code, the income tax laws of any municipality,
state or foreign country in which Purchaser may reside, and the tax consequences
of Purchaser's death.

             Purchaser agrees that he will execute and deliver to the Company
with this executed Agreement a copy of the Acknowledgment and Statement of
Decision Regarding Section 83(b) Election (the "Acknowledgment"), attached
hereto as Exhibit D. Purchaser further agrees that Purchaser will execute and
submit with the Acknowledgment a copy of the 83(b) Election, attached hereto as
Exhibit E, if Purchaser has indicated in the Acknowledgment his or her decision
to make such an election.

        9. MARKET STANDOFF AGREEMENT. In connection with the initial public
offering of the Company's securities and upon request of the Company or the
underwriters managing any underwritten offering of the Company's securities,
Purchaser agrees not to sell, make any short sale of, loan, grant any option for
the purchase of, or otherwise dispose of any Shares (other than those included
in the registration) without the prior written consent of the Company or such
underwriters, as the case may be, for such period of time (not to exceed 180
days) from the effective date of such registration as may be requested by the
Company or such managing underwriters and to execute an agreement reflecting the
foregoing as may be requested by the underwriters at the time of the Company's
initial public offering.

        11. MISCELLANEOUS.

             (a) GOVERNING LAW. This Agreement and all acts and transactions
pursuant hereto and the rights and obligations of the parties hereto shall be
governed, construed and interpreted in accordance with the laws of the State of
California, without giving effect to principles of conflicts of law.

             (b) ENTIRE AGREEMENT; ENFORCEMENT OF RIGHTS. This Agreement sets
forth the entire agreement and understanding of the parties relating to the
subject matter herein and merges all prior discussions between them. No
modification of or amendment to this Agreement, nor any waiver of any rights
under this Agreement, shall be effective unless in writing signed by the parties
to this Agreement. The failure by either party to enforce any rights under this
Agreement shall not be construed as a waiver of any rights of such party.

             (c) SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith. In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (i) such
provision shall be excluded from this Agreement, (ii) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (iii)
the balance of the Agreement shall be enforceable in accordance with its terms.

             (d) CONSTRUCTION. This Agreement is the result of negotiations
between and has been reviewed by each of the parties hereto and their respective
counsel, if any; accordingly,


                                     - 7 -
<PAGE>   62

this Agreement shall be deemed to be the product of all of the parties hereto,
and no ambiguity shall be construed in favor of or against any one of the
parties hereto.

             (e) NOTICES. Any notice required or permitted by this Agreement
shall be in writing and shall be deemed sufficient when delivered personally or
sent by telegram or fax or forty-eight (48) hours after being deposited in the
U.S. mail, as certified or registered mail, with postage prepaid, and addressed
to the party to be notified at such party's address as set forth below or as
subsequently modified by written notice.

             (f) COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original and all of which
together shall constitute one instrument.

             (g) SUCCESSORS AND ASSIGNS. The rights and benefits of this
Agreement shall inure to the benefit of, and be enforceable by the Company's
successors and assigns. The rights and obligations of Purchaser under this
Agreement may only be assigned with the prior written consent of the Company.

             (h) CALIFORNIA CORPORATE SECURITIES LAW. THE SALE OF THE SECURITIES
WHICH ARE THE SUBJECT OF THIS AGREEMENT HAS NOT BEEN QUALIFIED WITH THE
COMMISSIONEER OF CORPORATIONS OF THE STATE OF CALIFORNIA AND THE ISSUANCE OF THE
SECURITIES OR THE PAYMENT OR RECEIPT OF ANY PART OF THE CONSIDERATION THEREFOR
PRIOR TO THE QUALIFICATION IS UNLAWFUL, UNLESS THE SALE OF SECURITIES IS EXEMPT
FROM QUALIFICATION BY SECTION 25100, 25102 OR 25105 OF THE CALIFORNIA
CORPORATIONS CODE. THE RIGHTS OF ALL PARTIES TO THIS AGREEMENT ARE EXPRESSLY
CONDITIONED UPON THE QUALIFICATION BEING OBTAINED, UNLESS THE SALE IS SO EXEMPT.



                            [Signature Page Follows]



                                     - 8 -
<PAGE>   63

        The parties have executed this Agreement as of the date first set forth
above.

                                       PDF SOLUTIONS, INC.

                                       By:
                                          ------------------------------------

                                       Title:
                                             ---------------------------------
                                       Address:
                                       333 West San Carlos Street, Suite 700
                                       San Jose, CA 95110


                                       PURCHASER:

                                       <<Optionee>>

                                       ------------------------------------
                                       (Signature)

                                       Address:

                                       ------------------------------------

                                       ------------------------------------

Monthly Vesting
Date: __ of each month


I, ________________________________, spouse of <<Optionee>>, have read and
hereby approve the foregoing Agreement. In consideration of the Company's
granting my spouse the right to purchase the Shares as set forth in the
Agreement, I hereby agree to be irrevocably bound by the Agreement and further
agree that any community property or other such interest shall be similarly
bound by the Agreement. I hereby appoint my spouse as my attorney-in-fact with
respect to any amendment or exercise of any rights under the Agreement.



                                       ------------------------------------
                                       Spouse of <<Optionee>>



                                     - 9 -
<PAGE>   64


                                    EXHIBIT A

                                 PROMISSORY NOTE


$ ________                                                __________, California
                                                           _______________, 2000


        For value received, the undersigned promises to pay PDF Solutions, Inc.,
a California corporation (the "Company"), at its principal office the principal
sum of $ ______ with interest from the date hereof at a rate of _____% per
annum, compounded semiannually, on the unpaid balance of such principal sum.
Such principal and interest shall be due and payable on the fourth anniversary
of the date of this note.

        If the undersigned's employment or consulting relationship with the
Company is terminated prior to payment in full of this Note, this Note shall be
immediately due and payable.

        Principal and interest are payable in lawful money of the United States
of America. AMOUNTS DUE UNDER THIS NOTE MAY BE PREPAID AT ANY TIME WITHOUT
INTEREST OR PENALTY.

        Should suit be commenced to collect any sums due under this Note, such
sum as the Court may deem reasonable shall be added hereto as attorneys' fees.
The makers and endorsers have severally waived presentment for payment, protest,
notice of protest, and notice of nonpayment of this Note.

        This Note, which is full recourse, is secured by a pledge of certain
shares of Common Stock of the Company and is subject to the terms of a Pledge
and Security Agreement between the undersigned and the Company of even date
herewith.

                                       ------------------------------------
                                       <<Optionee>>


<PAGE>   65

                                    EXHIBIT B

                          PLEDGE AND SECURITY AGREEMENT


        This Pledge and Security Agreement (the "Agreement") is entered into
this day of ___________, 2000 by and between PDF Solutions, Inc., a California
corporation (the "Company") and <<Optionee>> ("Purchaser").

                                    RECITALS

        In connection with Purchaser's purchase of certain shares of the
Company's Common Stock (the "Shares") pursuant to a Restricted Stock Purchase
Agreement dated _____________________, 2000 between Purchaser and the Company,
Purchaser is delivering a promissory note of even date herewith (the "Note") in
full or partial payment of the exercise price for the Shares. The Company
requires that the Note be secured by a pledge of the Shares on the terms set
forth below.

                                    AGREEMENT

        In consideration of the Company's acceptance of the Note as full or
partial payment of the exercise price of the Shares, and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the parties
hereto agree as follows:

        1. The Note shall become payable in full upon the voluntary or
involuntary termination or cessation of employment of Purchaser with the
Company, for any reason, with or without cause (including death or disability).

        2. Purchaser shall deliver to the Secretary of the Company, or his or
her designee (hereinafter referred to as the "Pledge Holder"), all certificates
representing the Shares, together with an Assignment Separate from Certificate
in the form attached to this Agreement as Attachment A executed by Purchaser and
by Purchaser's spouse (if required for transfer), in blank, for use in
transferring all or a portion of the Shares to the Company if, as an when
required pursuant to this Agreement. In addition, if Purchaser is married,
Purchaser's spouse shall execute the signature page attached to this Agreement.

        3. As security for the payment of the Note and any renewal, extension or
modification of the Note, Purchaser hereby grants to the Company a security
interest in and pledges with and delivers to the Company Purchaser's Shares
(sometimes referred to herein as the "Collateral").

        4. In the event that Purchaser prepays all or a portion of the Note, in
accordance with the provisions thereof, Purchaser intends, unless written notice
to the contrary is delivered to the Pledge Holder, that the Shares represented
by the portion of the Note so repaid, including annual interest thereon, shall
continue to be so held by the Pledge Holder, to serve as independent collateral
for the outstanding portion of the Note for the purpose of commencing the
holding period set forth in Rule 144(d) promulgated under the Securities Act of
1933, as amended (the "Securities Act").


<PAGE>   66

        5. In the event of any foreclosure of the security interest created by
this Agreement, the Company may sell the Shares at a private sale or may
repurchase the Shares itself. The parties agree that, prior to the establishment
of a public market for the Shares of the Company, the securities laws affecting
sale of the Shares make a public sale of the Shares commercially unreasonable.
The parties further agree that the repurchasing of such Shares by the Company,
or by any person to whom the Company may have assigned its rights under this
Agreement, is commercially reasonable if made at a price determined by the Board
of Directors in its discretion, fairly exercised, representing what would be the
fair market value of the Shares reduced by any limitation on transferability,
whether due to the size of the block of shares or the restrictions of applicable
securities laws.

        6. In the event of default in payment when due of any indebtedness under
the Note, the Company may elect than, or at any time thereafter, to exercise all
rights available to a secured party under the California commercial Code
including the right to sell the Collateral at a private or public sale or
repurchase the Shares as provided above. The proceeds of any sale shall be
applied in the following order:

                    (a) To the extent necessary, proceeds shall be used to pay
all reasonable expenses of the Company in enforcing this Agreement and the Note,
including, without limitation, reasonable attorney's fees and legal expenses
incurred by the Company.

                    (b) To the extent necessary, proceeds shall be used to
satisfy any remaining indebtedness under Purchaser's Note.

                    (c) Any remaining proceeds shall be delivered to Purchaser.

        7. Upon full payment by Purchaser of all amounts due under the Note,
Pledge Holder shall deliver to Purchaser all Shares in Pledge Holder's
possession belonging to Purchaser, and Pledge Holder shall thereupon be
discharged of all further obligations under this Agreement; provided, however,
that Pledge Holder shall nevertheless retain the Shares as escrow agent if at
the time of full payment by Purchaser said Shares are still subject to a
Repurchase Option in favor of the Company.



                                     - 2 -
<PAGE>   67

The parties have executed this Pledge and Security Agreement as of the date
first set forth above.


                                       COMPANY:

                                       PDF SOLUTIONS, Inc.

                                       By:
                                          -------------------------------------

                                       Name:
                                            -----------------------------------
                                            (print)

                                       Title:
                                             ----------------------------------

                                       Address:
                                       333 West San Carlos Street, Suite 700
                                       San Jose, CA 95110


                                       PURCHASER:

                                       <<Optionee>>

                                       ------------------------------------
                                       (Signature)

                                       Address:

                                       ------------------------------------

                                       ------------------------------------



                                     - 3 -
<PAGE>   68

                                  ATTACHMENT A

                      ASSIGNMENT SEPARATE FROM CERTIFICATE


        FOR VALUE RECEIVED and pursuant to that certain Pledge and Security
Agreement between the undersigned ("Purchaser") and PDF Solutions, Inc., dated
_____________, 2000 (the "Agreement"), Purchaser hereby sells, assigns and
transfers unto _______________________________ (________) shares of the Common
Stock of PDF Solutions, Inc., standing in Purchaser's name on the books of said
corporation represented by Certificate No. ___ herewith and hereby irrevocably
appoints _____________________________ to transfer said stock on the books of
the within-named corporation with full power of substitution in the premises.
THIS ASSIGNMENT MAY ONLY BE USED AS AUTHORIZED BY THE AGREEMENT.

Dated: ____________

                                       Signature:


                                       ------------------------------------
                                       <<Optionee>>

                                       ------------------------------------
                                       Spouse of <<Optionee>> (if applicable)



Instruction: Please do not fill in any blanks other than the signature line. The
purpose of this assignment is to perfect the security interest of the Company
pursuant to the Agreement.


<PAGE>   69

                                    EXHIBIT C

                      ASSIGNMENT SEPARATE FROM CERTIFICATE


        FOR VALUE RECEIVED and pursuant to that certain Restricted Stock
Purchase Agreement between the undersigned ("Purchaser") and PDF Solutions,
Inc., dated ____________2000 (the "Agreement"), Purchaser hereby sells, assigns
and transfers unto _________________________________ (________) shares of the
Common Stock of PDF Solutions, Inc., standing in Purchaser's name on the books
of said corporation represented by Certificate No. ___ herewith and does hereby
irrevocably constitute and appoint
________________________________________________ to transfer said stock on the
books of the within-named corporation with full power of substitution in the
premises. THIS ASSIGNMENT MAY ONLY BE USED AS AUTHORIZED BY THE AGREEMENT AND
THE EXHIBITS THERETO.

Dated: ______________________

                                   Signature:


                                       ------------------------------------
                                       <<Optionee>>


                                       ------------------------------------
                                       Spouse of <<Optionee>> (if applicable)



Instruction: Please do not fill in any blanks other than the signature line. The
purpose of this assignment is to enable the Company to exercise its repurchase
option set forth in the Agreement without requiring additional signatures on the
part of Purchaser.


<PAGE>   70

                                    EXHIBIT D

                    ACKNOWLEDGMENT AND STATEMENT OF DECISION
                        REGARDING SECTION 83(b) ELECTION

        The undersigned (which term includes the undersigned's spouse), a
purchaser of <<NoofShares>> shares of Common Stock of PDF Solutions, Inc., a
California corporation (the "Company") by exercise of stock purchase right (the
"Right"), hereby states as follows:

        1.      The undersigned has carefully reviewed the stock purchase
agreement pursuant to which the Right was granted.

        2.      The undersigned either [check and complete as applicable]:

        (a)____ has consulted, and has been fully advised by, the
                undersigned's own tax advisor, __________________________, whose
                business address is _____________________________, regarding the
                federal, state and local tax consequences of purchasing these
                shares, and particularly regarding the advisability of making
                elections pursuant to Section 83(b) of the Internal Revenue Code
                of 1986, as amended (the "Code") and pursuant to the
                corresponding provisions, if any, of applicable state law; or

        (b)____ has knowingly chosen not to consult such a tax advisor.

        3.      The undersigned hereby states that the undersigned has decided
[check as applicable]:

        (a)____ to make an election pursuant to Section 83(b) of the Code,
                and is submitting to the Company, together with the
                undersigned's executed Restricted Stock Purchase Agreement, an
                executed form entitled "Election Under Section 83(b) of the
                Internal Revenue Code of 1986;" or

        (b)____ not to make an election pursuant to Section 83(b) of the Code.

        4.      Neither the Company nor any subsidiary or representative of the
Company has made any warranty or representation to the undersigned with respect
to the tax consequences of the undersigned's purchase of shares or of the making
or failure to make an election pursuant to Section 83(b) of the Code or the
corresponding provisions, if any, of applicable state law.


Date:
-----------------------------------    -----------------------------------
                                       <<Optionee>>

Date:
-----------------------------------    -----------------------------------
                                       Spouse of <<Optionee>>


<PAGE>   71
                                    EXHIBIT E

                          ELECTION UNDER SECTION 83(b)
                      OF THE INTERNAL REVENUE CODE OF 1986

        The undersigned taxpayer hereby elects, pursuant to Section 83(b) of the
Internal Revenue Code, to include in taxpayer's gross income for the current
taxable year, the amount of any compensation taxable to taxpayer in connection
with taxpayer's receipt of the property described below:

1.      The name, address, taxpayer identification number and taxable year of
        the undersigned are as follows:

        NAME OF TAXPAYER: <<Optionee>>

        NAME OF SPOUSE:  _______________

        ADDRESS: ________________________________________

                 ________________________________________

        IDENTIFICATION NO. OF TAXPAYER:  _______________

        IDENTIFICATION NO. OF SPOUSE:  _______________

        TAXABLE YEAR:  _______________

2.      The property with respect to which the election is made is described as
        follows:

        <<NoofShares>> shares of the Common Stock (the "Shares"), $0.0001 par
        value, of PDF Solutions, Inc., a California corporation (the "Company").

3.      The date on which the property was transferred is:  _______________

4.      The property is subject to the following restrictions:

        Repurchase option at cost in favor of the Company upon termination of
        taxpayer's employment or consulting relationship.

5.      The fair market value at the time of transfer, determined without regard
        to any restriction other than a restriction which by its terms will
        never lapse, of such property is: $ _______.

6.      The amount (if any) paid for such property:  $ ________.

The undersigned has submitted a copy of this statement to the person for whom
the services were performed in connection with the undersigned's receipt of the
above-described property. The transferee of such property is the person
performing the services in connection with the transfer of said property.

The undersigned understands that the foregoing election may not be revoked
except with the consent of the Commissioner.

Date:
-----------------------------------    -----------------------------------
                                       <<Optionee>>

Date:
-----------------------------------    -----------------------------------
                                       Spouse of <<Optionee>>