摘要
固定频率AC-DC的PWM芯片广泛应用于低功率电源中,并一直是业界研究的热点技术。本文概论精确控制此类芯片的输出过功率的三种方法,(1)减小过流保护(Over Current Protecting,简称OCP)的延迟时间T_d,(2)调整OCP的电压阈值和(3)同时调整延迟时间和电压阈值,通过计算分析其优缺点,为芯片的OCP过功率设计提供了技术细节参考。
The fixed-frequency AC-DC PWM IC has been widely used in low-power switching power supply and is a very hot technique that people are devoted to all along.This paper presents three different methods to limit the power precisely:(1)Decreasing the delay time of over current protecting(OCP)(2) Modulating the threshold voltage of OCP and(3)Changing both of them. Through analyzing and comparing these three methods,this paper gives some valuable details for the design of system s power limiting.
出处
《电源技术应用》
2008年第11期32-36,共5页
Power Supply Technologles and Applications
关键词
PWM芯片
OCP
功率限制
延迟时间
PWM IC
Over Current Protecting
Power limiting
delay time
