一种用于心电/脑电采集的电流反馈放大器  

A Current-Feedback Instrumentation Amplifier for ECG/EEG Acquisition

作　　者：徐乃昊[1,2] 姜汉钧[1,2] 王湾[1,2] 王自强[1,2] 王志华[1,2] 

机构地区：[1]清华大学微电子学研究所,北京100084 [2]北京市无线医疗和健康工程技术研究中心,北京100084

出　　处：《微电子学》2016年第1期25-28,共4页Microelectronics

基　　金：国家自然科学基金资助项目(61474070);清华大学自主科研项目(2012087960)

摘　　要：提出了一种用于采集心电、脑电信号的低功耗、低噪声电流反馈型仪表放大器。在经典结构的基础上增加了电平转换电路,实现了轨到轨输出;采用后台数字失配校准电路校准差分电极失配。采用0.18μm CMOS工艺对电路进行设计和仿真。仿真结果表明,增益为57dB时,最大可校准输入失配为3.1mV;在0~100Hz范围内,等效输入噪声为1.5μV（rms）,满足心电、脑电信号采集需求;在1.8V电源电压下,电流消耗仅为1.7μA。A low-power low-noise instrumentation amplifier（IA）dedicated for electrocardiogram（ECG）and electroencephalogram（EEG）acquisition systems was presented.A DC-coupled current-feedback structure was adopted.The output voltage range was expanded to rail-to-rail by adding a novel level shifting circuit between the forward amplifier and the feedback network.A background digitally-assisted offset calibration method was used to calibrate the differential electrode offset.The current-feedback IA was designed in a standard 0.18μm CMOS technology.The simulation results showed that the offset up to 3.1mV could be calibrated out under a gain setting of 57 dB.The input referred noise of the IA was 1.5μV（rms）at 0-100 Hz,which could meet the requirements for the ECG and EEG acquisition systems.The total operating current was only 1.7μA from a 1.8Vsupply.

关 键 词：仪表放大器 失配校准 轨到轨输出 

分 类 号：TN432[电子电信—微电子学与固体电子学]