The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 24, 2012
Filed:
Aug. 07, 2009
Bin Zhao, Irvine, CA (US);
Andrew M. Kameya, Irvine, CA (US);
Victor K. Lee, Irvine, CA (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A pulse width modulation (PWM) frequency converter converts an input PWM signal to an output PWM signal having a different frequency while maintaining a substantially equal duty ratio. The PWM frequency converter samples the input PWM signal for a PWM cycle using a sampling clock. A filter module filters the resulting set of one or more PWM parameters to compensate for noise introduced by potential clock mismatch, clock jitter, ambient variations, and other non-deterministic issues, thereby generating filtered PWM parameters. The sampling employed by the filter module compares a difference between the one or more current PWM parameters and previous (or historical) PWM parameters from an earlier sampled PWM cycle to a predetermined change threshold in determining a filtered set of one or more PWM parameters. The filtered set of one or more PWM parameters then is used to generate one or more corresponding PWM cycles of the output signal.