一种用于心电信号检测的低噪声斩波放大器  

A Low Noise Chopper-Stabilized Amplifier for ECG Signal Detection

作　　者：张琦[1] ZHANG Qi(The 20th Research Institute of China Electronics Technology Group Corporation,Xi'an 780068,P.R.China)

机构地区：[1]中国电子科技集团公司第二十研究所,西安710068

出　　处：《微电子学》2020年第5期643-648,共6页Microelectronics

摘　　要：提出了一种适用于心电信号(ECG)检测的斩波调制放大器。基于现有的局部斩波调制放大器,采用全局斩波调制方式优化了电路噪声性能;采用正反馈阻抗提升技术显著提高了输入阻抗。首次提出了替代传统共源共栅结构的电流分裂式结构方案,有效降低了运放的基底噪声。采用TSMC 0.18μm CMOS工艺对该放大器进行了仿真验证。结果表明,在1.8 V电源电压下,功耗仅为8.6μW,在0.1~100 Hz范围内等效积分噪声为0.26μV·Hz^-1/2,输入阻抗为417 MΩ,共模抑制比达138 dB。A chopper-stabilized amplifier for ECG signal detection was presented.Based on the available local chopper-stabilized circuit,a global chopper modulation method was employed to optimize the noise performance.A positive feedback loop was proposed to boost the input impedance of the circuit.The current-splitting structure was first proposed to replace the traditional common-source common-gate structure,which effectively reduced the floor noise of the operational amplifier.The amplifier was simulated with the TSMC 0.18μm CMOS technology.The results showed that,the total power consumption was only 8.6μW at 1.8 V supply,the input-referred noise was 0.26μV·Hz^-1/2 within the range of 0.1~100 Hz,the input impedance was 417 MΩ,and the common-mode rejection ratio was 138 dB.

关 键 词：全局斩波调制 阻抗提高 电流分裂式 低噪声放大器 

分 类 号：TN722.3[电子电信—电路与系统]