Patent ID: 8058810
Filing Date: 2011-11-15
Classification: H03K,H05B

Abstract:
1. A light emitting diode (LED) driver for supplying an LED bus voltage to a large array of LEDs organized in multiple channels with one or more LEDs connected in series in each channel, comprising: a power converter configured for providing the LED bus voltage to the multiple LED channels based on a voltage control signal; a feedback generation circuit configured for generating a feedback signal based on the LED bus voltage supplied to the multiple LED channels; and a phase-division based controller configured for generating the voltage control signal based on the feedback signal and information from the multiple LED channels, wherein the phase-division based controller divides each pulse width modulation (PWM) dimming cycle associated with each channel into a tracking phase and a pre-charging phase, and the LED bus voltage supplied to the multiple channels changes between the tracking phase and the pre-charging phase.