Color sequential LED backlight power system with ripple-free circuits for large-scale LCD panels

This paper presents a color sequential light-emitting diode (LED) backlight power system for large-scale LCD panels. The proposed power system uses ripple-free circuit to improve image quality. In the proposed circuit structure, a set of power converter is operated in interleaving fashion and with switching regulation for generating two sets of output voltages to respectively supply red, green and blue LEDs by switch control. With this approach, an inductor for achieving ripple-free feature is adopted in each phase of the proposed interleaving converter. Compared to the conventional color-sequential LED backlight power system, the proposed power converter can be reduced its power converter counts, size, volume and cost, and increased its conversion efficiency significantly. Simulated results obtained from the proposed power system have been verified its feasibility.