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In recent years, under the situation of global warming, energy crisis situation, "green" power, low power consumption technology has become a hot field of switching power supply development. As a green illumination source, LED (Light Emitting Diode) is lower power consumption, higher reliability and longer life-span than common illumination source. High-power LED lighting is widely used in street lighting, landscape light, car headlight lighting and other different areas. But power source need to transfer AC to DC, because of the characteristic of LED. The process of the transformation may introduce harmonic currents that can cause several problems such as voltage distortion,heating,noises,and reduce the energy efficiently.Therefore, the application of power factor correction (PFC) technology can reduce the content of harmonic currents, so it can get rid of several problems.This paper introduced the characteristics and reliability of LED, the principle and development of PFC. Then the paper compared some topology structures and the control strategies of active power factor correction. According to the results of comparing, the topology structure and control strategy of the PFC chip were designed. The application circuit with the proposed PFC has these features: 100W output power, 400V output voltage, 12V output voltage ripple, 100kHz switching frequency, -25~125℃temperature range. The circuit has over 90% efficiency, 0.95 power factor, having achieved the design specification.This paper analyzed some sub-block, such as PFC block, reliable protection block and logic control block. Every circuits were designed and simulated on 0.5um 15V BCD process. Furthermore, they all have been simulated by Hspice and Cadence software. At last, all the simulation results presented that every typical performance characteristics simulation were satisfied, so the chip has good performance on PFC.
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