A novel sequential-color RGB-LED backlight driving system with local dimming control and dynamic bus voltage regulation

Higher luminance efficacy, wider color gamut, lower power consumption, faster response, longer operation life, lesser environmental impacts, and local dimming capability make RGB LED backlight driving system suitable for high end LCD applications. In this paper, a digitally controlled four-phase interleaved RGB LED backlight driving system for LCD panels is proposed. Field color sequential (FCS) techniques, local dimming control (LDC) and dynamic bus voltage regulation (DBVR) technologies are implemented in the proposed system. FCS can improve the power efficiency and image quality, LDC can reduce the power consumption and enhance the image contrast ratio and DBVR can maximize the driving system´s efficiency. Only one power converter is required in the proposed system; therefore the system configuration is very simple. Finally, experimental results are provided to validate the effectiveness and correctness of the proposed system. According to the experimental results, the presented system can successfully drive the RGB LED backlight module, and the color-mixing, local dimming and bus voltage regulation functions can be successfully realized.