A Bipolar Process Based On The Low Cost Of Pfc Chip Design

Along with the development of the power rectifier technology, control of the current harmonic pollution and efficient use of energy has become a new research hotspot, and this of course promoted the rapid development of the power factor correction technology. With technology advances, the active power factor correction will eventually replace the passive power factor correction, and it will become the mainstream of power factor correction.This project is based on BJT process, and it is an active power factor correction chip with One Cycle Control, it is designed with a special power factor correction technology-One Cycle Control technology which is different from the traditional multiplier-based power factor correction. The One Cycle Control is based on a mathematical deduce, and it is suitable for the application with power factor correction. This kind of chip has the following advantages:it works on the basis of continuous current mode of Boost topology, its input can be90V to265V, AC input frequency at50Hz or60Hz, the output of this chip is385V DC whose ripple is10V, its PF can be over0.99.At first this article will introduce and analysis the OCC theory and the various working mode switching. Then considering the control of this chip, this article will introduce the design and simulation of reference source, oscillator, current sampling adder, error protection, over voltage protection, under voltage lock, output drivers. At last, the author carries out a whole circuit simulation and chip layout verification. After flow, the author tested and analyzed the single device and circuit module, this of course proof our former parameters. During the tests, we also found some difference between design specifications and process parameters, after this, the author had a general analysis of the reason of these problems, which is a more useful instruction of the latter circuit modification and simulation.