Random PWM dimming control for LED backlight

摘要

In one aspect of the invention, a driver for driving a backlight module having a plurality of LED strings includes a random frequency multiplexer for receiving one or more PWM signals and responsively outputting a plurality of random frequency signals, a PWM dimming controller electrically coupled to the random frequency multiplexer for receiving the plurality of random frequency signals and responsively outputting a plurality of driving signals to the plurality of LED strings to drive each of the plurality of LED strings, respectively, and a switching control circuit LX electrically coupled to the random frequency multiplexer for receiving the plurality of random frequency signals and responsively outputting a plurality of switching control signals to a boost converter to regulate duty cycle ON/OFF of each of the plurality of driving signals, respectively, so as to cause each of the plurality of LED strings to emit light of a desired brightness within a desired timing cycle.