基于DSP的双输入BUCK变换器在LED驱动器中的应用

摘要

This paper presents a scheme that the two-input BUCK (TIBUCK) converter is applied to the LED drivers. The performance characteristics of the circuit are analyzed in detail. The TIBUCK converter is designed to operate in the voltage control mode governed by DSP, thus the output current can be adjusted well and the LEDs can then work in the constant current mode. The simulation and experimental results show that the voltage stress of switch and diode in the TIBUCK converter are reduced, and the constant current control for the output current is realized at the same time. Thereby, as the constant-current part of the LED driver, the feasible of the TIBUCK converter is proved.%提出一种将双输入Buck(TIBUCK)变换器应用于LED驱动器的方案，并详细分析该电路的性能特点。该TIBUCK变换器采用电压模式控制，由DSP作为控制核心，能够很好地调节输出电流，使LED工作在恒流状态。仿真和实验结果表明， TIBUCK变换器在降低开关管和二极管电压应力的同时实现了对输出电流的恒流控制，从而证明该变换器作为LED驱动器中的后级恒流部分是可行的。