A current detection circuit with high-precision and wide-range common-mode input voltage
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.
current detectionwide-rangehigh-precisionlogic control
NETL
NSTL
万方数据
