September 10, 2019

Sandeep Nayyar
Chief Financial Officer
Power Integrations, Inc.
5245 Hellyer Avenue
San Jose, CA, 95138

       Re: Power Integrations, Inc.
           Form 10-K for the Fiscal Year Ended December 31, 2018
           Filed February 13, 2019
           File No. 000-23441

Dear Mr. Nayyar:

       We have reviewed your filing and have the following comments. In some of
our
comments, we may ask you to provide us with information so we may better
understand your
disclosure.

       Please respond to these comments within ten business days by providing
the requested
information or advise us as soon as possible when you will respond. If you do
not believe our
comments apply to your facts and circumstances, please tell us why in your
response.

       After reviewing your response to these comments, we may have additional
comments.

Form 10-K for the Fiscal Year Ended December 31, 2018

Note 11. Provision (Benefit) For Income Taxes, page 53

1.     We note from your tax rate reconciliation on page 54 that foreign income
taxed at lower
       rates significantly impacted your effective tax rates in each of the
reported periods. Please
       revise future filings to provide greater insight into the nature of this
reconciling item,
       including the primary taxing jurisdictions where your foreign earnings
are derived and the
       relevant statutory rates in those jurisdictions. Disclose any
incentivized tax rates you have
       been granted and briefly describe the factual circumstances of any tax
holidays, the per
       share effects of the tax holiday, and the date upon which any special
tax status terminates.
       Refer to ASC 740-10-50-12 and SAB Topic 11.C.
 Sandeep Nayyar
FirstName LastNameSandeep Nayyar
Power Integrations, Inc.
Comapany 10, 2019
September NamePower Integrations, Inc.
September 10, 2019 Page 2
Page 2
FirstName LastName
2.       In future filings, revise your MD&A on page 28 to explain the impact
of non-U.S. lower
         taxed jurisdictions on your effective tax rate, including a discussion
of the primary taxing
         jurisdictions where your foreign earnings are derived, the location of
any tax holidays and
         the relevant statutory rates in those jurisdictions. Discuss any
uncertainties relating to the
         income tax rates or benefits you currently receive in those
jurisdictions. Refer to Item
         303(a)(3) of Regulation S-K and Section III.B of SEC Release 33-8350.
        We remind you that the company and its management are responsible for
the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action
or absence of
action by the staff.

        You may contact Eric Atallah at (202) 551-3663 or Kevin Kuhar,
Accounting Branch
Chief, at (202) 551-3662 with any questions.



                                                                Sincerely,

                                                                Division of
Corporation Finance
                                                                Office of
Electronics and Machinery