Design of an ultra-low-power second order sigma-delta ADC

Abstract

Sigma-Delta analogue-to-digital converters (ADC) are used in various electronic circuits in which low power consumption and high-resolution are key considerations as mentioned in the work[ 1] and [2].The operation of LLl ADCs relies on the combination of two signal processing strategies: that of oversampling quantization error filtering and that of feedback, also known as noise shaping. As described in [2], because of these two techniques, LLl ADCs offer very low sensitivity to analogue circuit errors and achieve high SNR and dynamic ranges, thus enabling the detection and processing of sensor signals, including bio-potential signals.