Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement Nos. 333-232803, 333-214240, 333-183126, 333-152455, 333-146025, 333-122370, 333-119015, 333-112135, 333-102676, 333-86270, 333-59564, 333-42194, 333-83083, 333-69871 and 333-56381 on Form S-8 of our reports dated February 5, 2021, relating to the financial statements of Power Integrations, Inc. and the effectiveness of Power Integrations, Inc.’s internal control over financial reporting appearing in this Annual Report on Form 10-K for the year ended  December 31, 2020.

/s/ DELOITTE & TOUCHE LLP

San Jose, California

February 5, 2021