Abstract: The present invention relates to methods for LED driver applications, comprising the steps: providing an input voltage, Vin; generating an output voltage, Vout, for driving a plurality of LED channels, wherein a boost converter is used to convert the input voltage Vin to the output voltage Vout; determining a lowest voltage, VLVS, from the LED channels; generating a comparator voltage, Vcomp, by comparing the lowest voltage of the channels, VLVS, with a feedback reference voltage, VFBREF, wherein the feedback reference voltage, VFBREF, and a LED current, ILED, for the LED channels are determined by a current ISET; generating a summed voltage, Vsum, for stabilizing the output voltage, Vout; and generating a PWM voltage, VPWM, as a function of the Vcomp and the Vsum to control the output voltage, Vout.
Type:
Grant
Filed:
November 17, 2009
Date of Patent:
March 5, 2013
Assignee:
LePower Semiconductor Inc.
Inventors:
Ronald Chang, Chin-Chi Chang, Chung-Kuang Huang
Abstract: The present invention relates to methods for LED driver applications, comprising the steps: providing an input voltage, Vin; generating an output voltage, Vout, for driving a plurality of LED channels, wherein a boost converter is used to convert the input voltage Vin to the output voltage Vout; determining a lowest voltage, VLVS, from the LED channels; generating a comparator voltage, Vcomp, by comparing the lowest voltage of the channels, VLVS, with a feedback reference voltage, VFBREF, wherein the feedback reference voltage, VFBREF, and a LED current, ILED, for the LED channels are determined by a current ISET; generating a summed voltage, Vsum, for stabilizing the output voltage, Vout; and generating a PWM voltage, VPWM, as a function of the Vcomp and the Vsum to control the output voltage, Vout.
Type:
Application
Filed:
November 17, 2009
Publication date:
November 18, 2010
Applicant:
LEPOWER SEMICONDUCTOR INC.
Inventors:
Ronald Chang, Chin-Chi Chang, Chung-Kuang Huang