POWER INTEGRATIONS, INC. NONSTATUTORY STOCK OPTION AGREEMENT

Exhibit 10.9

POWER INTEGRATIONS, INC.

NONSTATUTORY STOCK OPTION AGREEMENT

FOR OUTSIDE DIRECTORS

THIS NONSTATUTORY STOCK OPTION AGREEMENT FOR OUTSIDE DIRECTORS (the “Option Agreement”) is made and entered into as of                                                      , by and between Power Integrations, Inc. and                                      (the “Optionee”).

The Company has granted to the Optionee an option to purchase certain shares of Stock pursuant to the Directors Equity Compensation Program under the 2007 Equity Incentive Plan upon the terms and conditions set forth in this Option Agreement (the “Option”). In the event of any conflict between the provisions of the Option Agreement and those of the Plan, the provisions of the Option Agreement shall control.

1. Definitions and Construction.

1.1 Definitions. Whenever used herein, the following terms shall have their respective meanings set forth below:

(a) “Date of Option Grant” means                             .

(b) “Number of Option Shares” means                              shares of Stock, as adjusted from time to time pursuant to Section 9.

(c) “Exercise Price” means $             per share of Stock, as adjusted from time to time pursuant to Section 9.

(d) “Initial Exercise Date” means the Initial Vesting Date.

(e) “Initial Vesting Date” means                             .

(f) “Vested Ratio” means, on any relevant date, the ratio determined as follows:

(g) “Option Expiration Date” means the date ten (10) years after the Date of Option Grant.

(h) “Board” means the Board of Directors of the Company. If one or more Committees have been appointed by the Board to administer the Plan, “Board” shall also mean such Committee(s).

(i) “Code” means the Internal Revenue Code of 1986, as amended, and any applicable regulations promulgated thereunder.

(j) “Committee” means a committee of the Board duly appointed to administer the Plan and having such powers as shall be specified by the Board. Unless the powers of the Committee have been specifically limited, the Committee shall have all of the powers of the Board granted in the Plan, including, without limitation, the power to amend or terminate the Plan at any time, subject to the terms of the Plan and any applicable limitations imposed by law.

(k) “Company” means Power Integrations, Inc., a Delaware corporation, or any successor corporation thereto.

(l) “Consultant” means any person, including an advisor, engaged by a Participating Company to render services other than as an Employee or a Director.

(m) “Director” means a member of the Board or of the board of directors of any other Participating Company.

(n) “Disability” means the permanent and total disability of the Optionee within the meaning of Section 22(e)(3) of the Code.

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(o) “Employee” means any person treated as an employee (including an officer or a Director who is also treated as an employee) in the records of a Participating Company; provided, however, that neither service as a Director nor payment of a director’s fee shall be sufficient to constitute employment for purposes of the Plan.

(p) “Exchange Act” means the Securities Exchange Act of 1934, as amended.

(q) “Fair Market Value” means, as of any date, the value of a share of Stock or other property as determined by the Board, in its sole discretion, or by the Company, in its sole discretion, if such determination is expressly allocated to the Company herein, subject to the following:

(i) If, on such date, there is a public market for the Stock, the Fair Market Value of a share of Stock shall be the closing sale price of a share of Stock (or the mean of the closing bid and asked prices of a share of Stock if the Stock is so quoted instead) as quoted on the Nasdaq National Market, the Nasdaq Small-Cap Market or such other national or regional securities exchange or market system constituting the primary market for the Stock, as reported in the Wall Street Journal or such other source as the Company deems reliable. If the relevant date does not fall on a day on which the Stock has traded on such securities exchange or market system, the date on which the Fair Market Value shall be established shall be the last day on which the Stock was so traded prior to the relevant date, or such other appropriate day as shall be determined by the Board, in its sole discretion.

(ii) If, on such date, there is no public market for the Stock, the Fair Market Value of a share of Stock shall be as determined by the Board without regard to any restriction other than a restriction which, by its terms, will never lapse.

(r) “Parent Corporation” means any present or future “parent corporation” of the Company, as defined in Section 424(e) of the Code.

(s) “Participating Company” means the Company or any Parent Corporation or Subsidiary Corporation.

(t) “Participating Company Group” means, at any point in time, all corporations collectively which are then Participating Companies.

(u) “Plan” means the Power Integrations, Inc. 2007 Equity Incentive Plan.

(v) “Securities Act” means the Securities Act of 1933, as amended.

(w) “Service” means the Optionee’s service with the Participating Company Group, whether in the capacity of an Employee, a Director or a Consultant. The Optionee’s Service shall not be deemed to have terminated merely because of a change in the capacity in which the Optionee renders Service to the Participating Company Group or a change

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in the Participating Company for which the Optionee renders such Service, provided that there is no interruption or termination of the Optionee’s Service. The Optionee’s Service shall be deemed to have terminated either upon an actual termination of Service or upon the corporation for which the Optionee performs Service ceasing to be a Participating Company.

(x) “Stock” means the common stock of the Company, as adjusted from time to time in accordance with Section 9.

(y) “Subsidiary Corporation” means any present or future “subsidiary corporation” of the Company, as defined in Section 424(f) of the Code.

1.2 Construction. Captions and titles contained herein are for convenience only and shall not affect the meaning or interpretation of any provision of this Option Agreement. Except when otherwise indicated by the context, the singular shall include the plural, the plural shall include the singular, and the term “or” shall include the conjunctive as well as the disjunctive.

2. Tax Status of the Option. This Option is intended to be a nonstatutory stock option and shall not be treated as an incentive stock option within the meaning of Section 422(b) of the Code.

3. Administration. All questions of interpretation concerning this Option Agreement shall be determined by the Board, including any duly appointed Committee of the Board. All determinations by the Board shall be final and binding upon all persons having an interest in the Option. Any officer of a Participating Company shall have the authority to act on behalf of the Company with respect to any matter, right, obligation, or election which is the responsibility of or which is allocated to the Company herein, provided the officer has apparent authority with respect to such matter, right, obligation, or election.

4. Exercise of the Option.

4.1 Right to Exercise. Except as otherwise provided herein, the Option shall be exercisable on and after the Initial Exercise Date and prior to the termination of the Option (as provided in Section 6) in an amount not to exceed the Number of Option Shares multiplied by the Vested Ratio less the number of shares previously acquired upon exercise of the Option. In no event shall the Option be exercisable for more shares than the Number of Option Shares.

4.2 Method of Exercise. Exercise of the Option shall be by written notice to the Company which must state the election to exercise the Option, the number of whole shares of Stock for which the Option is being exercised and such other representations and agreements as to the Optionee’s investment intent with respect to such shares as may be required pursuant to the provisions of this Option Agreement. The written notice must be signed by the Optionee and must be delivered in person, by certified or registered mail, return receipt requested, by confirmed facsimile transmission, or by such other means as the Company may permit, to the Chief Financial Officer of the Company, or other authorized representative of the Participating Company Group, prior to the termination of the Option as set forth in Section 6, accompanied by

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full payment of the aggregate Exercise Price for the number of shares of Stock being purchased. The Option shall be deemed to be exercised upon receipt by the Company of such written notice and the aggregate Exercise Price.

4.3 Payment of Exercise Price.

(a) Forms of Consideration Authorized. Except as otherwise provided below, payment of the aggregate Exercise Price for the number of shares of Stock for which the Option is being exercised shall be made (i) in cash, by check, or cash equivalent, (ii) by tender to the Company of whole shares of Stock owned by the Optionee having a Fair Market Value not less than the aggregate Exercise Price, (iii) by means of a Cashless Exercise, as defined in Section 4.3(c), or (iv) by any combination of the foregoing.

(b) Tender of Stock. Notwithstanding the foregoing, the Option may not be exercised by tender to the Company of shares of Stock to the extent such tender of Stock would constitute a violation of the provisions of any law, regulation or agreement restricting the redemption of the Company’s stock. The Option may not be exercised by tender to the Company of shares of Stock unless such shares either have been owned by the Optionee for more than six (6) months or were not acquired, directly or indirectly, from the Company.

(c) Cashless Exercise. A “Cashless Exercise” means the assignment in a form acceptable to the Company of the proceeds of a sale or loan with respect to some or all of the shares of Stock acquired upon the exercise of the Option pursuant to a program or procedure approved by the Company (including, without limitation, through an exercise complying with the provisions of Regulation T as promulgated from time to time by the Board of Governors of the Federal Reserve System). The Company reserves, at any and all times, the right, in the Company’s sole and absolute discretion, to decline to approve or terminate any such program or procedure.

4.4 Tax Withholding. At the time the Option is exercised, in whole or in part, or at any time thereafter as requested by the Company, the Optionee agrees to make adequate provision for any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Participating Company Group, if any, which arise in connection with the Option, including, without limitation, obligations arising upon (i) the exercise, in whole or in part, of the Option, (ii) the transfer, in whole or in part, of any shares acquired upon exercise of the Option, or (iii) the lapsing of any restriction with respect to any shares acquired upon exercise of the Option.

4.5 Certificate Registration. Except in the event the Exercise Price is paid by means of a Cashless Exercise, the certificate for the shares as to which the Option is exercised shall be registered in the name of the Optionee, or, if applicable, the heirs of the Optionee.

4.6 Restrictions on Grant of the Option and Issuance of Shares. The grant of the Option and the issuance of shares of Stock upon exercise of the Option shall be subject to compliance with all applicable requirements of federal, state or foreign law with respect to such securities. The Option may not be exercised if the issuance of shares of Stock upon exercise

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would constitute a violation of any applicable federal, state or foreign securities laws or other law or regulations or the requirements of any stock exchange or market system upon which the Stock may then be listed. In addition, the Option may not be exercised unless (i) a registration statement under the Securities Act shall at the time of exercise of the Option be in effect with respect to the shares issuable upon exercise of the Option or (ii) in the opinion of legal counsel to the Company, the shares issuable upon exercise of the Option may be issued in accordance with the terms of an applicable exemption from the registration requirements of the Securities Act. THE OPTIONEE IS CAUTIONED THAT THE OPTION MAY NOT BE EXERCISED UNLESS THE FOREGOING CONDITIONS ARE SATISFIED. ACCORDINGLY, THE OPTIONEE MAY NOT BE ABLE TO EXERCISE THE OPTION WHEN DESIRED EVEN THOUGH THE OPTION IS VESTED. The inability of the Company to obtain from any regulatory body having jurisdiction the authority, if any, deemed by the Company’s legal counsel to be necessary to the lawful issuance and sale of any shares subject to the Option 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. As a condition to the exercise of the Option, the Company may require the Optionee to satisfy any qualifications that may be necessary or appropriate, to evidence compliance with any applicable law or regulation and to make any representation or warranty with respect thereto as may be requested by the Company.

4.7 Fractional Shares. The Company shall not be required to issue fractional shares upon the exercise of the Option.

5. Nontransferability of the Option. The Option may be exercised during the lifetime of the Optionee only by the Optionee or the Optionee’s guardian or legal representative and may not be assigned or transferred in any manner except by will or by the laws of descent and distribution. Following the death of the Optionee, the Option, to the extent provided in Section 7, may be exercised by the Optionee’s legal representative or by any person empowered to do so under the deceased Optionee’s will or under the then applicable laws of descent and distribution.

6. Termination of the Option. The Option shall terminate and may no longer be exercised on the first to occur of (a) the Option Expiration Date, (b) the last date for exercising the Option following termination of the Optionee’s Service as described in Section 7, or (c) a Change in Control to the extent provided in Section 8.

7. Effect of Termination of Service.

7.1 Option Exercisability.

(a) Disability. If the Optionee’s Service with the Participating Company Group is terminated because of the Disability of the Optionee, the Option, to the extent unexercised and exercisable on the date on which the Optionee’s Service terminated, may be exercised by the Optionee (or the Optionee’s guardian or legal representative) at any time prior to the expiration of twelve (12) months after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date.

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(b) Death. If the Optionee’s Service with the Participating Company Group is terminated because of the death of the Optionee, the Option, to the extent unexercised and exercisable on the date on which the Optionee’s Service terminated, may be exercised by the Optionee’s legal representative or other person who acquired the right to exercise the Option by reason of the Optionee’s death at any time prior to the expiration of twelve (12) months after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date. The Optionee’s Service shall be deemed to have terminated on account of death if the Optionee dies within three (3) months after the Optionee’s termination of Service.

(c) Other Termination of Service. If the Optionee’s Service with the Participating Company Group terminates for any reason, except Disability or death, the Option, to the extent unexercised and exercisable by the Optionee on the date on which the Optionee’s Service terminated, may be exercised by the Optionee within three (3) months after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date.

7.2 Extension if Exercise Prevented by Law. Notwithstanding the foregoing, if the exercise of the Option within the applicable time periods set forth in Section 7.1 is prevented by the provisions of Section 4.6, the Option shall remain exercisable until three (3) months after the date the Optionee is notified by the Company that the Option is exercisable, but in any event no later than the Option Expiration Date.

7.3 Extension if Optionee Subject to Section 16(b). Notwithstanding the foregoing, if a sale, within the applicable time periods set forth in Section 7.1, of shares acquired upon the exercise of the Option would subject the Optionee to suit under Section 16(b) of the Exchange Act, the Option shall remain exercisable until the earliest to occur of (i) the tenth (10th) day following the date on which a sale of such shares by the Optionee would no longer be subject to such suit, (ii) the one hundred and ninetieth (190th) day after the Optionee’s termination of Service, or (iii) the Option Expiration Date.

8. Ownership Change and Change in Control.

8.1 Definitions.

(a) An “Ownership Change Event” shall be deemed to have occurred if any of the following occurs with respect to the Company:

(i) the direct or indirect sale or exchange in a single or series of related transactions by the shareholders of the Company of more than fifty percent (50%) of the voting stock of the Company;

(ii) a merger or consolidation in which the Company is a party;

(iii) the sale, exchange, or transfer of all or substantially all of the assets of the Company; or

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(iv) a liquidation or dissolution of the Company.

(b) A “Change in Control” shall mean an Ownership Change Event or a series of related Ownership Change Events (collectively, the “Transaction”) wherein the shareholders of the Company immediately before the Transaction do not retain immediately after the Transaction, in substantially the same proportions as their ownership of shares of the Company’s voting stock immediately before the Transaction, direct or indirect beneficial ownership of more than fifty percent (50%) of the total combined voting power of the outstanding voting stock of the Company or the corporation or corporations to which the assets of the Company were transferred (the “Transferee Corporation(s)”), as the case may be. For purposes of the preceding sentence, indirect beneficial ownership shall include, without limitation, an interest resulting from ownership of the voting stock of one or more corporations which, as a result of the Transaction, own the Company or the Transferee Corporation(s), as the case may be, either directly or through one or more subsidiary corporations. The Board shall have the right to determine whether multiple sales or exchanges of the voting stock of the Company or multiple Ownership Change Events are related, and its determination shall be final, binding and conclusive.

8.2 Effect of Change in Control on Option. In the event of a Change in Control, any unexercised portion of the Option shall be immediately exercisable and vested in full as of the date ten (10) days prior to the date of the Change in Control. Any exercise of the Option that was permissible solely by reason of this Section 8.2 shall be conditioned upon the consummation of the Change in Control. In addition, the surviving, continuing, successor, or purchasing corporation or parent corporation thereof, as the case may be (the “Acquiring Corporation”), may either assume the Company’s rights and obligations under the Option or substitute for the Option a substantially equivalent option for the Acquiring Corporation’s stock. The Option shall terminate and cease to be outstanding effective as of the date of the Change in Control to the extent that the Option is neither assumed or substituted for by the Acquiring Corporation in connection with the Change in Control nor exercised as of the date of the Change in Control. Notwithstanding the foregoing, shares acquired upon exercise of the Option prior to the Change in Control and any consideration received pursuant to the Change in Control with respect to such shares shall continue to be subject to all applicable provisions of this Option Agreement except as otherwise provided herein. Furthermore, notwithstanding the foregoing, if the corporation the stock of which is subject to the Option immediately prior to an Ownership Change Event described in Section 8.1(a)(i) constituting a Change in Control is the surviving or continuing corporation and immediately after such Ownership Change Event less than fifty percent (50%) of the total combined voting power of its voting stock is held by another corporation or by other corporations that are members of an affiliated group within the meaning of Section 1504(a) of the Code without regard to the provisions of Section 1504(b) of the Code, the Option shall not terminate.

9. Adjustments for Changes in Capital Structure. In the event of any stock dividend, stock split, reverse stock split, recapitalization, combination, reclassification, or similar change in the capital structure of the Company, appropriate adjustments shall be made in the number, Exercise Price and class of shares of stock subject to the Option. If a majority of the shares which are of the same class as the shares that are subject to the Option are exchanged for,

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converted into, or otherwise become (whether or not pursuant to an Ownership Change Event) shares of another corporation (the “New Shares”), the Board may unilaterally amend the Option to provide that the Option is exercisable for New Shares. In the event of any such amendment, the Number of Option Shares and the Exercise Price shall be adjusted in a fair and equitable manner, as determined by the Board, in its sole discretion. Notwithstanding the foregoing, any fractional share resulting from an adjustment pursuant to this Section 9 shall be rounded down to the nearest whole number, and in no event may the Exercise Price be decreased to an amount less than the par value, if any, of the stock subject to the Option.

10. Rights as a Shareholder. The Optionee shall have no rights as a shareholder with respect to any shares covered by the Option until the date of the issuance of a certificate for the shares for which the Option has been exercised (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company). No adjustment shall be made for dividends, distributions or other rights for which the record date is prior to the date such certificate is issued, except as provided in Section 9.

11. Legends. The Company may at any time place legends referencing any applicable federal, state or foreign securities law restrictions on all certificates representing shares of stock subject to the provisions of this Option Agreement. The Optionee shall, at the request of the Company, promptly present to the Company any and all certificates representing shares acquired pursuant to the Option in the possession of the Optionee in order to carry out the provisions of this Section.

12. Binding Effect. Subject to the restrictions on transfer set forth herein, this Option Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective heirs, executors, administrators, successors and assigns.

13. Termination or Amendment. The Board may terminate or amend the Plan or the Option at any time; provided, however, that no such termination or amendment may adversely affect the Option or any unexercised portion hereof without the consent of the Optionee unless such termination or amendment is necessary to comply with any applicable law, regulation or rule. No amendment or addition to this Option Agreement shall be effective unless in writing.

14. Integrated Agreement. This Option Agreement constitutes the entire understanding and agreement of the Optionee and the Participating Company Group with respect to the subject matter contained herein, and there are no agreements, understandings, restrictions, representations, or warranties among the Optionee and the Participating Company Group with respect to such subject matter other than those as set forth or provided for herein. To the extent contemplated herein, the provisions of this Option Agreement shall survive any exercise of the Option and shall remain in full force and effect.

15. Applicable Law. This Option Agreement shall be governed by the laws of the State of Delaware as such laws are applied to agreements between Delaware residents entered into and to be performed entirely within the State of Delaware.

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The Optionee represents that the Optionee is familiar with the terms and provisions of this Option Agreement and hereby accepts the Option subject to all of the terms and provisions thereof. The Optionee hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Board upon any questions arising under this Option Agreement.

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