Analog front-end measuring biopotential signal with effective offset rejection loop

Seunghyun Lim; Hyunho Kim; Haryong Song; Dong-il Dan Cho; Hyoungho Ko

doi:10.3233/BME-151387

Analog front-end measuring biopotential signal with effective offset rejection loop

Biomed Mater Eng. 2015:26 Suppl 1:S935-41. doi: 10.3233/BME-151387.

Authors

Seunghyun Lim¹, Hyunho Kim¹, Haryong Song¹, Dong-il Dan Cho², Hyoungho Ko¹

Affiliations

¹ Department of Electronics, Chungnam National University, Daejeon 305-764, Korea.
² School of Electrical Engineering, ASRI/ ISRC, Seoul National University, Seoul 151-744, Korea.

PMID: 26406095
DOI: 10.3233/BME-151387

Abstract

This paper presents an analog front-end (AFE) IC design for recording biopotential signals. The AFE employs a capacitively coupled instrumentation amplifier to achieve a low-noise and high-common mode rejection ratio (CMRR) system. A ripple reduction loop is proposed to reduce the ripple generated by the up-modulating chopper. The low frequency noise is attenuated by an input AC coupling capacitor, and is attenuated again by a DC servo loop. The proposed AFE features a differential gain of 71 dB, and a CMRR of 89 dB, at 50 Hz. Furthermore, the proposed AFE can robustly acquire biopotential signals even in the presence of an input offset and ripples.

Keywords: Biopotential analog front-end (AFE); DC servo loop; electrocardiogram (ECG); electroencephalograph (EEG); ripple reduction loop.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Algorithms
Amplifiers, Electronic
Electrocardiography / instrumentation*
Electrocardiography / methods
Electrophysiological Phenomena
Equipment Design
Humans