Exhibit 32.1

Certification of Chief Executive Officer and Chief Financial Officer

Pursuant to 18 U.S.C. § 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, each of the undersigned officers of Silicon Laboratories Inc. (the “Company”) hereby certifies that:

(i)the accompanying Quarterly Report on Form 10-Q of the Company for the fiscal quarter ended March 30, 2024 as filed with the Securities and Exchange Commission (the “Report”) fully complies with the requirements of Section 13(a) or Section 15(d), as applicable, of the Securities Exchange Act of 1934, as amended; and

(ii)the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: April 24, 2024

/s/ R. Matthew Johnson

R. Matthew Johnson

President and

Chief Executive Officer

/s/ Mark D. Mauldin

Mark D. Mauldin

Interim Chief Financial Officer