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. 13, 2012
Filed:
Apr. 12, 2010
Ta-yung Yang, Milpitas, CA (US);
Chien-yuan Lin, Taipei County, TW;
Chien-tung Lan, Taipei, TW;
System General Corporation, Sindian, Taipei County, TW;
Abstract
An offline LED driving circuit includes a controller, a shunt regulator, an opto-coupler, and a dimming circuit. The controller generates a switching signal to switch a transformer for providing an output voltage and an output current. The shunt regulator is coupled to an output terminal of the LED driving circuit for providing a feedback signal to the controller via the opto-coupler. The dimming circuit coupled to the shunt regulator modulates the feedback signal at a first feedback level and a second feedback level in response to a dimming signal. The output voltage is respectively regulated at a first output level and a second output level in response to the first feedback level and the second feedback level of the feedback signal. The duty cycle of the switching signal will be varied in a soft-start manner when the feedback signal changes from the second feedback level to the first feedback level.