改CCFL驱动LED驱动.docVIP

改CCFL驱动为LED驱动实现液晶显示器改LED背光 Ouyxg 与CCFL背光相比，LED背光具有功耗低、使用寿命长以及白光更纯TL494，是功能非常完善的PWM驱动电路，常用于开关稳压电源的控制，也经常被用于CCFL驱动电路。 网购的19寸宽屏LED灯条，有两条；单条LED为9串5并，电压：24-27V，最大电流：100mA。 改制后的LED驱动电路 电路采用Boost DC-DC升压电路，在14v电源电压的驱动下可升压到24-27v，最大电流限制在90mA以下，LED灯条的亮度已经足够。电感线圈L101，L102，用E16磁芯，（从14w废日光灯电子镇流器中拆的）磁间隙0.8mm，用3xΦ0.25mm漆包线绕56圈。电路中R9由原来的20k改为33k，降低IC TL494/16脚的起控电压， R24由原来的62k改为3.3k，以尽可能的降低LED灯条电流取样电阻R101，R102的阻值；所有元件标注为10X的均为改动后的电路元件。可见电路改动很小。 原电路板正面 原电路板反面 改制后电路板正面 改制后电路板反面 点亮的LED灯条 组装步骤网上有很多资料，本文不再赘述。 North Gate Station and all the long distance Intercity, TRANS-province lines; North Gate Station currently runs the original counties, rural routes; Simon, station main, Yibin city, across the city, across the province and to the West of range line. Yibin city highway main station distribution table 3.1-6 station name grade accounted for to area (m2) Gao North Gate Station and all the long distance Intercity, TRANS-province lines; North Gate Station currently runs the original counties, rural routes; Simon, station main, Yibin city, across the city, across the province and to the West of range line. Yibin city highway main station distribution table 3.1-6 station name grade accounted for to area (m2) Gao2 North Gate Station and all the long distance Intercity, TRANS-province lines; North Gate Station currently runs the original counties, rural routes; Simon, station main, Yibin city, across the city, across the province and to the West of range line. Yibin city highway main station distribution table 3.1-6 station name grade accounted for to area (m2) Gao