Central Molecular Circuit For Monolithic Switching Power Supply Management Chip

Parts of sub-circuit of a monolithic SMPS (switching mode power supply) management chip are researched and designed in this thesis. A power MOSFET with breakdown voltage exceeds 730V is integrated on this chip. The working frequency of this chip is fixed at 60KHZ, and the maximum output power is about 8W. In addition, this chip includes some protective circuits, thus just some simple external components are needed to provide a complete solution of the switching power supply.Since this chip is utilized by the patent of Professor Chen Xingbi, which uses the ordinary CMOS process to integrate high voltage and low voltage devices, without using dielectric isolation or PN junction isolation (BCD process) technology, thus the cost of power integrated circuits is greatly reduced.First of all, this thesis briefly introduces the circuit topology, modulation and control mode of the typical SMPS, and then describes the SMPS chip structural framework and working principle in detail. Then, a detailed analysis of the SMPS management chip elements, such as anti-false trigger circuit, regulator module and voltage reference circuits, oscillator module and rising edge detect circuit, feedback module with current sense and blanking circuit, skip cycle mode control circuit is given. Finally, a simple introduction to the SMPS management chip layout and some performance test results.