一种单边输入阻抗可调的斩波放大器  

An Unilateral Input Impedance Adjustable Chopper Amplifier

作　　者：张三锋 翟鹏飞 周雄 李强[1] ZHANG Sanfeng;ZHAI Pengfei;ZHOU Xiong;LI Qiang(Institute of Integrated Circuits and Systems,School of Electronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 610054,P.R.China)

机构地区：[1]电子科技大学电子科学与工程学院低功耗集成电路与系统研究所,成都610054

出　　处：《微电子学》2021年第5期696-700,共5页Microelectronics

基　　金：国家自然科学基金资助项目(62090041,61904027,61534002);广东省重点领域研发计划项目(2018B030339001)。

摘　　要：提出了一种单边输入阻抗可调、无需纹波抑制的斩波放大器。通过单独调控电容耦合斩波放大器预充电时序,实现单边输入阻抗可调的放大器设计,这对于存在系统性源阻抗失配的信号检测是有意义的。同时还提出了一种高通型核心放大器,通过降低增益,达到了衰减因斩波调制引入的输出纹波的目的。因此,所提出的斩波放大器不再需要额外的纹波抑制电路。仿真结果显示,该斩波放大器具有61MΩ~53GΩ的直流单边输入阻抗可调范围,具有51.4dB的纹波抑制能力。An unilateral input impedance adjustable chopper amplifier was proposed without the ripple-rejection technique.By individually adjusting the pre-charging timing of the capacitively-coupled chopper amplifier,the unilateral input impedance adjustable amplifier was realized,which was meaningful for signal detection with systematic source impedance mismatch.And a high-pass core amplifier was proposed,which reduced the gain,thus attenuating the output ripple induced by the up-modulated low-frequency errors.Therefore,the proposed chopper amplifier had natural ripple rejection ability,which avoided using an additional circuit to filter the output ripple.The simulation results showed that the chopper amplifier had an DC input impedance adjustable range from 61MΩ~53 GΩand a ripple rejection capability of 51.4dB.

关 键 词：输入阻抗 斩波 放大器 纹波 

分 类 号：TN432[电子电信—微电子学与固体电子学]