An 8-channel 2.1 μ W0.017 mm2 0.04% Gain Mismatch Bio-potential Recording AFE using Group-Chopping Technique

Abstract

An 8-ch bin-potential recording AFE with less than 0.04% gain mismatch is presented. The proposed Group Chopping Instrumentation Amplifier (GCIA) exploits groupchopping scheme with 8 -phase non-overlapping clocks to achieve the lowest gain mismatch reported to date and improses between channel CMRR among all channels, while mitigating dynamic offsets at once. The proposed GCIA is the first in literature to mitigate gain mismatch for more than 2 channels. Fabricated in 0.18 mu m CMOS, it consumes 2.1 mu W/Ch. under 0.5V supply and achieves NEF of 2.1, sshile occupying 0.017 mm(2)/Ch.