基于磁阻效应的微直流非接触检测系统

A Micro DC Non-Contact Detection System Based on Magnetoresistance Effect

摘要: 为了实现微直流的非接触测量，文中设计了一种基于磁阻效应原理的新型测量系统。该系统采用地静磁屏蔽，利用差分放大电路，有效地增强了磁阻元件的信号输出，实现了对微电流进行测量时无需将电流串入测量回路，利用间接测量恒磁场强度的方法达到测量电流的目的。该系统灵敏度高，结构简单，测量稳定，可满足5 mA以上微直流的非接触测量需要。

Abstract: In order to realize the non-contact measurement of micro DC, a new measurement system based on the principle of magnetoresistance effect is designed. In this system, the differential amplifier circuit is used to enhance the signal output of the magnetoresistive element effectively. When the micro current is measured, it is unnecessary to pass through the measuring circuit, and the purpose of measuring the current is achieved by indirectly measuring the intensity of the constant magnetic field. The system has the advantages of high sensitivity, simple structure and stable measurement, which can meet the needs of non-contact measurement of micro DC over 5 mA.