一种低偏置电流、高输入阻抗运算放大器电路设计  

A circuit design of operational amplifier with low input bias current and high input impedance

作　　者：代松 唐毓尚 包磊 袁兴林 陈旺云 DAI Song;TANG Yu-shang;BAO Lei;YUAN Xin-lin;CHEN Wang-yun(Guizhou Zhenhua Fengguang semiconduactor Co.,Ltd)

机构地区：[1]贵州振华风光半导体有限公司

出　　处：《中国集成电路》2021年第10期46-50,共5页China lntegrated Circuit

摘　　要：基于双极工艺设计了一种低偏置电流、高输入阻抗运算放大器。采用超β管作为输入对管,同时引入新型基极电流补偿电路,使运算放大器具有低偏置电流、高输入阻抗特性。该电路基于40V双极工艺进行设计,仿真结果显示,常温下偏置电流为11pA,输入阻抗为1.88×10^(9)Ω,增益达到137dB,带宽达到1.3MHz。An operational amplifier circuit with low bias current and high input impedance is designed based on the bipolar process in this paper.The differential input stage with a new type of base current compensation circuit is designed base on super beta transistor.And amplifier feature extremely low input bias current and high input impedance differential.The amplifier circuit is designed based on 40V bipolar process.And the results of simulation show that the input bias current is 11pA,the input impedance is 1.88×10^(9)Ω,the gain is 137 dB and the bandwidth is 1.3 MHz at normal temperature.

关 键 词：运算放大器 双极工艺 偏置电流 输入阻抗 

分 类 号：TN402[电子电信—微电子学与固体电子学]