LED照明电源的驱动技术与应用

为了提高LED照明电源的可靠性,提出一种基于半桥开关电路的PFM恒流控制驱动方案,实现了大功率LED照明驱动。该电路利用半桥驱动频率可编程以及限流电感阻碍高频电流的特点,通过改变电路的工作频率,调节输出电流,实现恒流控制。实验结果表明,该电源具有输出功率大、尖峰电流小和晶体管电压应力小的优点,适用于大功率输出的场合。

LED lighting power drive technologies and applications

To improve the reliability of the LED driver, a new method of PFM constant-current control driving based on half-bridge switching circuits is proposed, and large power LED illumination driving control is achieved. Because the driving frequency of half-bridge is programmable, and limited current inductance can affect high frequency current, the output current is adjusted to achieved eonstant-current eontrol by changing the working frequeney of circuit. The test results show that the power has such advantages as high power output, low peak-current, and small transistor voltage stress, and it is suitable for high power output.