Research And Implementation Of High Current Micropower Synchronous Switching Regulator

The paper is based on the project"Theoretical Research and Design of Low Power for Power Management IC"and mainly discusses the principle of the high current and micropower synchronous Buck-Boost switching regulator.This paper analyzes the working principle of three basic topology of switching regulator in detail, expounds the power dissipation sources and puts forward a new design scheme of low power control circuit. And then, a high current and micropower synchronous Buck-Boost switching regulator is designed.The designed IC adopts a novel high efficiency feedback control circuit to decrease the power dissipation which control the working region and the switching sequence by detecting the relationship of the input and output voltage. The burst mode is entered to achieve high efficiency when working in the light load condition. The system introduces an external compensation technology to optimize the system stability and transient response in the voltage-mode control loop. Mealwhile, an improved current limit circuit can provide 1.2A output current and ameliorate the loading capacity effectively. Besides, the IC introduces synchronous rectification technology to increase the efficiency and save the area of the PCB board.The whole circuit is designed based on the 0.5μm CMOS process. The simulation and verification is completed by the EDA tools such as Workview, Hspice, etc. According to the simulation results, the funcion and performance of the whole circuit have met all the requirements.