基于GMR传感器的4～20 mA两线变送器芯片设计  

Design of a 4～20 mA two-wire transmitter based on GMR sensor

作　　者：吴迪[1] 钱正洪[1] 朱华辰[1] 白茹[1] 

机构地区：[1]杭州电子科技大学磁电子中心,浙江杭州310018

出　　处：《现代电子技术》2015年第8期159-162,共4页Modern Electronics Technique

基　　金：浙江省重大科技专项(2011C11047);浙江省"磁电子材料和器件"高校创新团队(2009[171]);浙江省重点科技创新团队(2010R50010)

摘　　要：巨磁电阻（GMR）传感器具有灵敏度高、线性度好、磁滞小等优异的性能,在工业控制等方面应用广泛。在涉及信号长距离传输的应用中,电压信号容易受线阻影响而衰减,因此通常采用电流环路传递信号。基于GMR传感器,设计了一套4～20 m A两线制电流环系统,其中包括调理电路、V/I转换电路、I/V转换电路三个部分。此系统具有结构简单,增益可调,灵敏度高和抗干扰能力强等特点,能够在400 k Hz的频率下正常工作,满足恶劣环境下应用的指标要求。The giant magnetoresistance（GMR）sensor exhibits excellent properties,e.g. high sensitivity,low nonlinearity and small hysteresis,and can be widely used in the industrial application. When the voltage signal transmits in a wire to a long distance for the application of the industrial control,the signal is easily distorted by the external environment. But the current signal will be transmitted without signal distortion. Therefore,a 4～20 mA twowire current loop system was designed based on the GMR sensor. It consists of conditioning circuit,V/I converting circuit and I/V converting circuit. The system has a simple structure,adjustable gain,high sensitivity and strong antiinterference ability,can work at a frequency greater than 400 kHz, and can meet the requirements of application in harsh environment.

关 键 词：GMR传感器 运算放大器 电流环 工业控制 

分 类 号：TN722.34[电子电信—电路与系统]