一种应用于DC/DC转换器的高效PWM控制电路的设计  

Design of A High-efficient PWM Control Circuit Application for DC/DC Converter

作　　者：陈程[1] 王慧芳[1] 徐祥柱[1] 周泽坤[1] 张波[1] 

机构地区：[1]电子科技大学电子薄膜与集成器件国家重点实验室,四川成都610054

出　　处：《中国集成电路》2011年第8期46-52,共7页China lntegrated Circuit

摘　　要：本文提出一种用于DC/DC转换器的高效PWM控制电路。该控制电路采用电流控制模式,在宽范围内有着良好的瞬态响应。斜坡补偿信号与误差放大器的输出信号进行叠加,叠加后的信号与电流采样信号进行比较,产生一个占空比信号控制功率管的通断。并且本PWM控制电路中的误差放大器与软启动结合在一起,实现输出电压平滑稳定上升,有效减少了输入电流和输出电压过冲现象,保护了系统安全。A High-efficient PWM control circuit which is applied to DC/DC converter is presented in this paper. Based on current-mode control, good transient response has been realized in wide range. Superimposed signal of slope compensation and error amplifier output is compared with the signal of current sense, then produce a duty cycle to control the power transistor off. Meanwhile, This PWM control circuit combine error amplifier with soft-start, which realize the voltage of output smooth and steady increase. It is effective to reduce input current and output voltage overshoot, and protect the system security.

关 键 词：DC/DC转换器 误差放大器 软启动 斜坡补偿 PWM比较器 

分 类 号：TM46[电气工程—电器] TN761[电子电信—电路与系统]