A low power analog front-end for portable biopotential acquisition systems

Abstract

An ultra-low power analog front end is presented to capture ExG (including ECG, EEG and EMG) signals. It consists of a capacitively coupled chopper instrument amplifier, a chopping spike filter and a VGA. Implemented in standard 0.35μm CMOS technology, this analog front end occupying 0.54 mm ² chip area, while consuming only 3.96μA from 3.3 V supply. Measurement results show an input-referred noise of 0.85 μVrms (0.5-100 Hz), 115dB CMRR, 100dB PSRR, and a noise efficiency factor of 6.48.