一种低噪声精密运算放大器  

A Low Noise Precision Operational Amplifier

作　　者：李伟东[1] 周远杰 王成鹤[1] LI Weidong;ZHOU Yuanjie;WANG Chenghe(The 24th Research Institute of China Electronics Technology Group Corporation,Chongqing 400060,P.R.China)

机构地区：[1]中国电子科技集团公司第二十四研究所,重庆400060

出　　处：《微电子学》2021年第6期854-859,共6页Microelectronics

摘　　要：基于40 V标准双极工艺,设计了一种低噪声精密运算放大器电路。该电路主要用于高精度、高分辨率系统。介绍了运算放大器总体架构以及工作原理,对低噪声精密运算放大器设计关键技术,如输入偏置电流降低、频率稳定性补偿、输入失调电压降低等,进行了分析。利用Spectre软件进行了仿真,并进行了流片验证。对芯片进行了实际测试,结果显示,在±15 V工作电压条件下,该放大器的输入偏置电流为2 nA,输入失调电压为10μV,大信号电压增益为132 dB,共模抑制比为135 dB,电源抑制比130 dB。电路满足高精度、高分辨率、低噪声等各种场合的应用需求。A low noise precision operational amplifier was designed in a 40 V bipolar process,which was used in high precision and high resolution systems.The whole structure and operation mechanism of the operational amplifier were introduced.The key design techniques of operational amplifier such as reduced input bias current,reduced input offset voltage and frequency compensation were analyzed in detail.Then the operational amplifier was simulated with Spectre tool,and it was fabricated and verified.The tested results indicated that,under±15 V power supplies,the device achieved an input bias current of 2 nA,an input offset voltage of 10μV,a large signal voltage gain of 132 dB,a common mode reject ratio of 135 dB,and a power supply reject ratio of 130 dB.The circuit met the requirements of high precision,high resolution and low noise applications.

关 键 词：低噪声精密运算放大器 输入偏置电流 输入失调电压 大信号电压增益 等效输入噪声 频率补偿 

分 类 号：TN431[电子电信—微电子学与固体电子学]