Exhibit 5.1

May 29, 2018

QuickLogic Corporation

1277 Orleans Drive

Sunnyvale, California 94089

Re: 13,513,510 Shares of Common Stock of QuickLogic Corporation and

Warrants to Purchase up to an additional 5,405,404 shares of Common Stock

Ladies and Gentlemen:

We are acting as counsel to QuickLogic Corporation, a Delaware corporation (the “Company”), in connection with the issuance and sale by the Company of 13,513,510 shares (the “Shares”) of the Company’s common stock, par value $0.001 per share (the “Common Stock”) and warrants (the “Warrants”) to purchase up to an additional 5,405,404 shares of Common Stock (the “Warrant Shares,” and together with the Shares and the Warrants, the “Securities”), pursuant to an Underwriting Agreement, dated as of May 24, 2018 (the “Underwriting Agreement”), by and between the Company and Craig-Hallum Capital Group LLC, as representative of the several underwriters named in Schedule I thereto.

In connection with the opinions expressed herein, we have examined such documents, records and matters of law as we have deemed relevant or necessary for purposes of such opinions. Based on the foregoing, and subject to the further limitations, qualifications and assumptions set forth herein, we are of the opinion that:

1. The Shares, when issued and delivered pursuant to the terms of the Underwriting Agreement against payment of the consideration therefor as provided in the Underwriting Agreement, will be validly issued, fully paid and nonassessable.

2. The Warrants, when issued and delivered pursuant to the terms of the Underwriting Agreement against payment of the consideration therefor as provided in the Underwriting Agreement, will constitute valid and binding obligations of the Company.

3. The Warrant Shares, when issued upon exercise of the Warrants pursuant to the terms of the Warrants, will be validly issued, fully paid and nonassessable.

In rendering the foregoing opinions, we have assumed that the resolutions authorizing the Company to issue, offer and sell the Securities will be in full force and effect at all times at which any Securities are offered or sold by the Company.

ALKHOBAR • AMSTERDAM • ATLANTA • BEIJING • BOSTON • BRISBANE • BRUSSELS • CHICAGO • CLEVELAND • COLUMBUS • DALLAS DETROIT • DUBAI • DÜSSELDORF • FRANKFURT • HONG KONG • HOUSTON • IRVINE • LONDON • LOS ANGELES • MADRID • MELBOURNE MEXICO CITY • MIAMI • MILAN • MINNEAPOLIS • MOSCOW • MUNICH • NEW YORK • PARIS • PERTH • PITTSBURGH • RIYADH SAN DIEGO • SAN FRANCISCO • SÃO PAULO • SHANGHAI • SILICON VALLEY • SINGAPORE • SYDNEY • TAIPEI • TOKYO • WASHINGTON

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The opinion in paragraph 2 is limited by bankruptcy, insolvency, reorganization, fraudulent transfer and fraudulent conveyance, voidable preference, moratorium or other similar laws and related regulations and judicial doctrines from time to time in effect relating to or affecting creditors’ rights generally, and by general equitable principles and public policy considerations, whether such principles and considerations are considered in a proceeding at law or at equity.

As to facts material to the opinions and assumptions expressed herein, we have relied upon oral or written statements and representations of officers and other representatives of the Company and others. The opinions expressed herein are limited to the laws of the State of New York and the General Corporation Law of the State of Delaware, in each case as currently in effect, and we express no opinion as to the effect of the laws of any other jurisdiction.

We hereby consent to the filing of this opinion as Exhibit 5.1 to the Current Report on Form 8-K dated the date hereof filed by the Company relating to the Company’s Registration Statement on Form S-3, as amended (File No. 333-215030), and to the reference to Jones Day under the caption “Legal Matters” in the prospectus supplement constituting a part of such Registration Statement. In giving such consent, we do not thereby admit that we are included in the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission promulgated thereunder.