The paper introduces the principle of LED drive power with the single-stage Power Factor Corrector(PFC). The structure principle of constant-voltage source AC/DC with single-stage PFC is analyzed and the solutions of the questions related to the constant-voltage source with single-stage PFC is given. It is a key part to design of constant-current,the principle and design step of constant-current drive chip BP2808 are given,meanwhile,the manual dimmable LED is added,the multi-resonant self-excited oscillator consisted by NE555 is used to generate a fixed frequency and produce 0. 09 %＜D＜99. 91% adjustable duty cycle pulse width modulation(PWM) output to adjust LED's light. The results show the design could achieve a wide range of adjustment duty cycle PWM pulse wave and it is satisfied with the requirements of the Power Factor Corrector, meanwhile, the high efficiency and low-cost is realized,the paper conform to the trend of the development of LED drive power.%论述了单级功率因数校正(PFC)LED驱动电源的设计思想,分析了单级PFC恒压源AC/DC构建原理,给出了单级PFC恒压源产生相关问题的解决办法,重点设计了恒流源部分,给出了恒流驱动芯片BP2808工作原理和设计步骤,同时,设计了手动调光部分,运用自激多谐振荡器NE555产生固定频率且占空比为0.09％＜D＜99.91％可调的PWM脉冲波去调节LED灯串的亮度,研究结果表明,能够实现宽范围占空比可调的PWM脉冲波,并且在满足功率因数要求的同时实现了高效率和低成本,符合LED驱动电源发展的趋势和潮流.
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