一种高精度宽范围共模输入的电流检测电路  

A current detection circuit with high-precision and wide-range common-mode input voltage

作　　者：张子同 江月艳[1] 李珂[1] 徐叶 ZHANG Zitong;JIANG Yueyan;LI Ke;XU Ye(The 58th Research Institute of China Electronics Technology Group Corporation,Wuxi 214035,China)

机构地区：[1]中国电子科技集团第五十八研究所,江苏无锡214035

出　　处：《微电子学与计算机》2024年第7期56-63,共8页Microelectronics & Computer

摘　　要：基于0.18μm HV SOI CMOS工艺,设计实现了一种应用于电流保护系统中的高精度宽范围共模输入的电流检测电路。该电路通过检测采样电阻上的压降来获取电流值变化量;同时基于包含了LDMOS管的保护电路单元实现了宽的共模电压变化范围。此外,通过电路内置的逻辑控制单元实现输入正负压状态下高低侧运放的切换使用,降低了功耗;利用差分放大器以及跨阻放大器对获取的信号值进行处理,提高了检测精度。测试结果表明,在25℃温度下电路总输出误差<0.67%,在-55℃~125℃温度范围内电路可承受-18V~80 V宽范围共模输入且带宽大于200 kHz,当输入电压在-18V~80 V范围内变化时,输出电压的变化小于40 mV。Based on 0.18μm HV SOI CMOS process,a high precision and wide range common mode input current detection circuit for current protection system is designed and implemented.The circuit obtains the variable volume of the current value by detecting the upper voltage of the sampling resistor.At the same time,the protection circuit unit of the LDMOS tube is used to achieve a wide-mode voltage change range.Furthermore,by utilizing the built-in logic control unit of the circuit,the high and low side op-amps are switched under positive and negative input pressure states to minimize power consumption.Differential amplifier and transresistance amplifier are used to process the obtained signal values,and the detection accuracy is improved.Test results demonstrate that the circuit exhibits a total output error of less than 0.67%at 25℃,and can withstand a wide range of common mode inputs from−18V to 80V with a bandwidth exceeding 200 kHz within the temperature range of−55℃to 125℃.The output voltage changes by less than 40 mV when the input voltage varies from−18V to 80V.

关 键 词：电流检测 宽范围 高精度 逻辑控制 

分 类 号：TN432[电子电信—微电子学与固体电子学]