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. 31, 2012
Filed:
Apr. 19, 2011
Zhimou Ren, Chengdu, CN;
Yunning Xie, Chengdu, CN;
Yu-chang Hsu, Taipei, TW;
O2Micro, Inc., Santa clara, CA (US);
Abstract
A controller for controlling power to an LED light source includes a control terminal and control circuitry coupled to the control terminal. The control terminal provides a control signal to control a transformer. A cycle of the control signal includes a charging period, a discharging period, and an adjusting period. The control circuitry controls a primary winding of the transformer to receive power during the charging period and controls a secondary winding of the transformer to discharge power to the LED light source during the discharging period. The control circuitry further varies a frequency of the control signal periodically by controlling the adjusting period.