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.

Date of Patent:
Dec. 30, 2014

Filed:

May. 12, 2014
Applicant:

Silergy Semiconductor Technology (Hangzhou) Ltd, Hangzhou, ZheJiang Province, CN;

Inventor:

Shenglun Chen, Hangzhou, CN;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H05B 37/02 (2006.01); H05B 39/00 (2006.01); H05B 33/08 (2006.01); H02M 3/335 (2006.01);
U.S. Cl.
CPC ...
H05B 33/0815 (2013.01); H02M 3/33523 (2013.01); H05B 33/0887 (2013.01); Y02B 20/346 (2013.01);
Abstract

The present invention relates to a controlling circuit and controlling method for an LED driver implemented as a flyback topology. The controlling circuit may be at a primary side of a transformer of the LED driver, and include a sampling circuit, an on time sensing circuit of an output diode, a regulating signal generator, and a PWM controller. The sampling circuit may generate a sampling signal indicating output current by sampling at the primary transformer side. The on time sensing circuit can detect an on time of the output diode. The regulating signal generator can generate a regulating signal by regulating the sampling signal, a voltage reference, and the on time of the output diode. The PWM controller may generate a controlling signal to control operation of a switching device of the LED driver to maintain a substantially constant output current in accordance with the regulating signal.


Find Patent Forward Citations

Loading…