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:
Mar. 12, 2013
Filed:
Oct. 20, 2010
Ming-jung Tsai, Chang-Hua, TW;
Kun-min Chen, Changhua County, TW;
Ching-sheng LI, Hsinchu County, TW;
Sung-ming Lai, Hsinchu, TW;
Ming-Jung Tsai, Chang-Hua, TW;
Kun-Min Chen, Changhua County, TW;
Ching-Sheng Li, Hsinchu County, TW;
Sung-Ming Lai, Hsinchu, TW;
Anpec Electronics Corporation, Hsinchu Science Park, Hsin-Chu, TW;
Abstract
A rotation speed control circuit for controlling a rotation speed of a fan includes: a rotation speed detector, for generating a rotation speed voltage according to a rotation speed signal corresponding to the rotation speed; a sample and hold element, coupled to the rotation speed detector, for sampling and storing the rotation speed voltage; an error amplifier, coupled to the sample and hold element, for controlling a voltage of a filter capacitor according to the rotation speed voltage and a reference voltage, to adjust an error voltage; and a pulse width modulation signal generator, coupled to the filter capacitor, for generating a pulse width modulation signal according to the error voltage and a triangle wave.