一种高CMRR低功耗生物电信号采集前端放大器  

A High CMRR Low Power CMOS Front-End Amplifier for Biopotential Signal Acquisition

作　　者：邹志革[1] 徐博 孙帆 雷鑑铭[1] ZOU Zhige XU Bo SUN Fan LEI Jianming(School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, P. R. Chin)

机构地区：[1]华中科技大学光学与电子信息学院,武汉430074

出　　处：《微电子学》2017年第5期605-608,共4页Microelectronics

摘　　要：设计了一种应用于生物电信号采集的前端放大器。采用间接电流反馈技术,提高了放大器的线性度和共模抑制比。采用负反馈环路,消除了采集过程中电极产生的极化电压。采用0.18μm混合信号CMOS工艺对电路进行设计,使用Cadence Spectre进行了仿真。结果表明,该电路在3V供电下消耗的静态电流为4.5μA,在0.3Hz^1.3kHz的增益带宽内增益为37dB,能够消除50mV的极化电压,共模抑制比为98dB(50Hz工频处),噪声效率因子为11.5。A front-end amplifier（FEA）intended for biopotential signal acquisition was designed.A novel indirect current feedback instrumentation amplifier（ICFIA）was employed to improve the linearity and common-mode rejection ratio（CMRR）of the FEA.A negative feedback loop was used to eliminate the differential electrode offset（DEO）generated in the electrodes during signal acquisition.The circuit was designed in a 0.18μm mixed-signal CMOS process and simulated with Cadence Spectre.The simulation results showed that the circuit consumed a 4.5μA current from a 3 Vsupply.The gain of the FEA was 37 dB at a gain bandwidth range from 0.3 Hz to1.3 kHz.A DEO of 50 mV was eliminated,and a CMRR of 98 dB was obtained at the mains frequency（50 Hz）.The noise efficiency factor（NEF）of the FEA was 11.5.

关 键 词：生物电信号 电极极化电压 间接电流反馈仪表放大器 

分 类 号：TN722[电子电信—电路与系统]