一种用于PWM变换器的斜坡补偿电路设计  

Design of a slope compensation circuit for PWM converter

作　　者：徐静平[1] 王虎[1] 钟德刚[1] 谭亚伟[1] 

机构地区：[1]华中科技大学电子科学与技术系,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2007年第9期66-69,共4页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60376019)

摘　　要：针对传统斜坡补偿的PWM变换器的电流输出能力会随着补偿电流的增加而下降的缺点,设计了一种用于峰值电流模式PWM变换器的斜坡补偿电路.通过改进系统箝位电路,使箝位电压能够随着补偿电流动态变化,从而保持系统的输出电流能力恒定,减小输出电压纹波.仿真采用CSMC 0.6μm工艺,结果表明:在输入电压大于1 V、占空比大于50%时,输出电压纹波在10 mV左右,大大提高了负载能力和系统稳定性.The output current in traditional slope compensation PWM converter would decrease with the increase of the compensation. A new slope compensation circuit for peak current mode PWM converter was designed. The voltage clamp circuit was improved to get a dynamic clamp voltage, aiming at holding the output current and decreasing the output voltage ripple. Hspice was simulated by CSMC 0.6μm technology. The results show that the output voltage ripple is about 10 mV when the input voltage is larger than 1 V and the duty cycle is higher than 50 %, indicating that the improved slope compensation circuit has greatly increased the load performance as well as the stability of the system.

关 键 词：峰值电流模式 PWM变换器 斜坡补偿 

分 类 号：TN702[电子电信—电路与系统]