A Clockless Method of Flicker Noise Suppression in Continuous-Time Acquisition of Biosignals

Abstract

This paper presents a novel chopping method allowing suppression of 1/f flicker noise in continuous-time acquisition systems without the need for a fixed-frequency clock, stochastically deriving the chopping signal from the input and hence achieving completely signal-dependent power consumption. The method is analysed, its basis of operation explained and a proof-of-concept implementation presented alongside simulated results demonstrating an increase in achieved SNR of more than 8 dB during acquisition of ECG, EAP and EEG signals.