Study And Application Of A Power Factor Correction Chip Without Multiplier

With the widespread application of electronic products, the electric power system harmonic pollution is becoming serious day by day. In traditional rectifier structures, the current harmonic content is too high and the power factor is too low. To solve this problem, many power factor correction methods are put forward. Power factor correction could not only reduce power harmonic pollution and line consumption, but also can benefit for energy conservation. Therefor studying on PFC has important realistic and economic significance.This paper first introduces the principle of Power Factor and topological structure of Power Factor Correction. And then, a design proposal of a PFC chip working in voltage mode without multiplier is presented. This design proposal includes the whole chip design, key modules design and simulation, and the whole chip simulation. The key modules consist of a novel over voltage protection circuit and a novel driver structure. These modules are simpler and lower power consumption than conditional structures to which achieve the same function.Based on 0.4μmBCD process and Hspice, the chip is simulated and taped out, and the test result satisfies requirements successfully.Any chip designed is for application. This paper designs a LED power system with this chip. Constant current control is achieved by this system with single-state flyback PFC structure. The method designing key parameters is introduced. The experiment shows that the Power Factor of this system is up to 98%. Therefor, this chip can be widely used.