POWER INTEGRATIONS INC — Director's Dealing 2010

Mar 9, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: POWER INTEGRATIONS INC (POWI)
CIK: 0000833640
Period of Report: 2010-03-08

Reporting Person: BALAKRISHNAN BALU (President and CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-03-08	Common Stock	S	4992	$38.7991	Disposed	257089	Indirect
2010-03-08	Common Stock	M	4000	$12.1	Acquired	261089	Indirect
2010-03-08	Common Stock	S	4000	$38.6709	Disposed	257089	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2010-03-08	Non-Qualified Stock Option (right to buy)	$12.1	M	4000	Disposed	2011-05-31	Common Stock (4000)	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	12959	Direct
Common Stock	21023	Indirect
Common Stock	21023	Indirect

Footnotes

F1: Includes 162 shares acquired under the POWI stock purchase plan on January 31, 2003; 478 shares acquired under the POWI stock purchase plan on July 31, 2003; 1781 shares acquired under the POWI stock purchase plan on January 31, 2004; 1230 shares acquired under the POWI stock purchase plan on January 31, 2005 and 1341 shares acquired under the POWI stock purchase plan on January 31, 2006.

F2: The range of prices for the enclosed transactions were $38.75 to $38.95.

Upon request by the SEC staff, the issuer, or any security holder of the issuer we will provide full information regarding the number of shares sold at each separate price.

F3: The range of prices for the enclosed transactions were $38.29 to $38.96.

Upon request by the SEC staff, the issuer, or any security holder of the issuer we will provide full information regarding the number of shares sold at each separate price.

F4: The Reporting Person disclaims beneficial ownership of the shares held by the trust except to the extent of his pecuniary interest therein, and this report should not be deemed an admission that the Reporting Person is the beneficial owner of the trust's shares for purposes of Section 16 or for any other purpose.

F5: This sale is pursuant to a 10B5-1 Sales Plan