集成电路与嵌入式系统2026，Vol.26Issue(4)：66-75,10.DOI:10.20193/j.ices2097-4191.2025.0142
一种宽带低偏流轨对轨运算放大器设计
Design of rail-to-rail operational amplifier with wide bandwidth and low offset current
赵洁 1权龙杰 1张芸凡 1刘裕 1郑亦康 1范世全 1常科 1王金磊 1张国和1
作者信息
- 1. 北京微电子技术研究所,北京 100076
- 折叠
摘要
Abstract
A two-stage operational amplifier with low input bias current,rail-to-rail input,high gain,and high bandwidth has been de-signed.This design combines a folded-cascode first stage with a class-AB output stage,incorporating a linear transconductance(Gm)loop and gain-boosting techniques.The first stage employs a folded-cascode architecture,achieving rail-to-rail input through parallel NMOS and PMOS input differential pairs.A dedicated current compensation scheme ensures a constant output impedance of the first stage.The second stage utilizes a class-AB output configuration,where a translinear loop precisely sets the quiescent current of the out-put stage,resulting in improved drive capability and reduced power consumption.Gain-boosting techniques are applied to further en-hance the output impedance of the cascode structure,thereby increasing the overall DC gain.The op-amp is fabricated in a SMIC 180 nm MS BCD CMOS process.After tape-out,a test platform is independently developed by designing the test circuitry and fabricating a cus-tom PCB board.Key parameters of a broadband low-input-bias-current operational amplifier,including input bias current,offset volt-age,open-loop gain,small-signal bandwidth,slew rate,and noise,are measured using an oscilloscope,network analyzer,and spectrum analyzer.Test results demonstrate that with a 2 pF load capacitor,the amplifier achieves a low-frequency gain of 90 dB and a gain-band-width product(GBW)of 380 MHz.关键词
轨对轨放大器/低输入偏置电流/折叠式共源共栅/模拟芯片测试Key words
folded cascode operational amplifier/low input bias current/rail-to-rail/analog integrated Circuit testing分类
信息技术与安全科学引用本文复制引用
赵洁,权龙杰,张芸凡,刘裕,郑亦康,范世全,常科,王金磊,张国和..一种宽带低偏流轨对轨运算放大器设计[J].集成电路与嵌入式系统,2026,26(4):66-75,10.
