一种适合于开关稳压器的新颖电流检测方法

针对开关稳压器中负载电流检测难以同时做到准确、同步和结构简单这一难题,结合自己多年工作经验,提出了一种新颖的开关稳压器负载电流检测的新方法。其基本原理是利用断续模式（DCM）下负载电流与同步管栅极驱动信号N_DRV的同步关系,通过检测该栅极信号来检测开关稳压器的输出负载电流。这种方法不仅使负载电流检测同步和准确,且同时克服检测电感平均电流带来的电路结构复杂及实现上的困难。该电路经过HSpice仿真验证,其仅消耗5μA的静态电流,工作状态良好。

Novel Current Testing Method Suitable for Switching Voltage Stabilizers

A method to test the load current of switching voltage stabilizers is presented to implement the aim of testing the load current synchronously and exactly,and meanwhile to achieve the simplization of the circuit structure.Based on the correlation between the load current and the grid signal N_DRV of synchronous switch in discontinuous conduction mode（DCM）,the output load current of switching voltage stabilizers is tested through detecting the grid signal.This technique mentioned above can not only detect the load current synchronously and exactly,but also overcome the circuit structure complexity brought about by the detection of the average inductance current.The Hspice simulation of the circuit indicates that the circuit only consumes 5μA quiescent current.