一种双通道零漂移运算放大器的设计  

Design of a Dual⁃channel Zero⁃drift Operational Amplifier

作　　者：韩前磊 黄立朝 孔祥艺 丁宁 HAN Qianlei;HUANG Lichao;KONG Xiangyi;DING Ning(The NO.58 Research Institute of China Electronics Technology Group Corp.,Wuxi,Jiangsu,214000,CHN)

机构地区：[1]中国电子科技集团公司第五十八研究所,江苏无锡214000

出　　处：《固体电子学研究与进展》2021年第2期143-148,共6页Research & Progress of SSE

摘　　要：设计了一款双通道、零漂移、轨到轨输入输出的运算放大器,可用于温度、压力传感器等精密信号采集领域。整体结构主要包括:带隙基准、振荡器、分频器、开关控制、主运放和调零运放模块。其中振荡器、分频器、基准偏置为共用模块,开关控制、主运放、调零运放在双通道中相互独立。基于Cadence仿真软件,采用国内0.5μm CMOS工艺完成流片,在工作电源2.7~5.5 V条件下,实现的性能指标为:输入失调电压<10μV,电源电流<1.8 mA,输入失调漂移<0.04μV/℃,共模抑制比>120 dB,电源抑制比>120 dB,开环增益>130 dB,过载恢复时间<50μs,噪声<35 nV/√Hz。该运算放大器具有高精密、零漂移的特征。A dual-channel,zero-drift,rail-to-rail input and output high-precision operational ampli⁃fier was designed in this paper,which could be used in precision signal acquisition fields such as tem⁃perature and pressure sensors.The overall structure mainly includes:band gap reference,oscillator,frequency divider,stitch control,main operational amplifier and zero-drift operational amplifier mod⁃ule.Among them,the oscillator,frequency divider,and reference bias are shared modules,and the switch control,main operational amplifier and zero-drift operational amplifier are independent of each other in the dual channels.Based on Cadence simulation software,the domestic 0.5μm CMOS pro⁃cess was used to complete tape out.Under the working power supply 2.7~5.5 V,the achieved perfor⁃mance indicators are:input offset voltage<10μV,power supply current<1.8 mA,input offset drift<0.04μV/℃,common mode rejection ratio>120 dB,power supply rejection ratio>120 dB,switch⁃ing gain>130 dB,overload recovery time<50μs and noise<35 nV/√Hz.This operational amplifier has high-precision and zero-drift characteristics.

关 键 词：高精密 零漂移 双通道 轨到轨 

分 类 号：TN433[电子电信—微电子学与固体电子学]