提出一种新型的RGB-LED背光驱动系统。一方面,引入时间混色法技术,LED可以选择性地导通和关闭,因此降低了电源的损耗,提高了电源效率；另一方面,采用电压自适应电路结构,对于RGB三种LED灯来说,其导通所需要的正向电压不同,电压自适应结构可以使加在LED灯串上的电压随着同步信号变化而变化,保证加在LED灯串上的电压始终为满足导通条件的最小电压,使系统的效率最大化。实验结果说明该系统可以成功驱动RGB-LED背光模块,电源效率得到提高,证明了该背光系统的可行性。

A new kind of RGB LED backlight driving system was introduced. On one hand, time blending method was introduced. Owing to sequential colors of RGB, the RGB LEDs could be controlled in an efficient way, thus reducing the power consumption. On the other hand, voltage adaptive structure was introduced. Based on the fact that the output voltage of the power converter has to change according to different LED chips with different forward voltage, the structure could guarantee that the power supply voltage is always the lowest and power efficiency is always the highest. The experiment results prove the correctness and feasibility of the system, which could successfully drive the RGB LED backlight module and improve the power supply efficiency.