A versatile rail to rail current mode instrumentation amplifier with an embedded band-pass filter for bio-potential signal conditioning

Abstract

A novel ultra low power, area-efficient, current-mode instrumentation amplifier (CMIA) with embedded bandpass filter, for acquisition of bio-potential signals is presented. A novel bias front-end is also presented, which achieves CMRR of 195dB at 1Hz in the presence of ±5% component mismatch. The CMIA has a tunable bandwidth, from 160Hz to 7.2kHz with input referred rms noise of 2.24 μV in frequency band of 5mHz to 160Hz. The CMIA is designed in 180nm mixed-mode CMOS technology and provides rail to rail output voltage of 1.65V(p-p) while dissipating 39 μW, at 1.8V supply voltage. The output of CMIA doesn't need any further signal conditioning.