An Energy-Recycling (ER) Technique for Field Color Sequential LCD Backlight Driving

Abstract

An energy-recycling (ER) technique has been proposed to implement high power conversion efficiency and low cost solution of field color sequential (FCS) LEDs backlight driving. One recycling capacitor C(R) and one power-transistor M(R) are added to synchronous boost converter to compose the ER function. When the output voltage of FCS-LEDs backlight driver switches from 40V to 26V for driving RGB LEDs during related time interval, ER technique stops to boost input voltage and switches to recycle energy from output terminal to the recycling capacitor CR. Thus, the output voltage can be rapidly switched between two different voltage levels with minimum power losses. The proposed ER technique has been fabricated by TSMC 40V BCD process. The experimental results demonstrate fast and efficient output voltage tracking performance is achieved by the proposed ER technique.