摘要
本文设计了一种指数型斜坡补偿电路,适用于峰值电流模式降压型DC-DC变换器,该电路利用固定的斜坡补偿斜率与指数型反斜坡补偿斜率的效果叠加得到补偿斜率随占空比连续变化的指数型补偿斜率,能够在低占空比时提供较小的斜坡补偿斜率,减小斜坡补偿对变换器带载能力的限制,在高占空比时提供足够的补偿斜率防止电路产生次谐波震荡。电路采用0.35μm BCD工艺,利用Hspice进行仿真,在变换器输入3.3V,占空比66%的条件下,反斜坡补偿电压斜率在导通时间达到设定值后开始呈现指数变化,证明了所设计电路的正确性。
A exponential slope compensation circuit applicable for buck converter working in peak-current mode has been designed.A fixed compensation slope is superimposed on a exponential compensation slope to obtain a compensative voltage,the slope varies from the duty ratio continuously.The circuit can supply a lesser gradient at a small duty,which can minimize the limit of output load caused by the slope compensation,and a sufficient gradient is produced at the high duty to avoid subharmonic oscillation.The0.35μm BCD process and Hspice have been used for simulation,When the input voltage of converter is3.3V,and the duty ratio is66%,the slope of anti-compensation is exponential after the setting time,which proves the validity of this design.
作者
屠浩
张国俊
Hao Tu;Guojun Zhang(State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China,Chengdu,Sichuan,610054, China)
出处
《电子科学技术》
2017年第3期22-26,共5页
Electronic Science & Technology
