A 112dB SNDR Delta-Sigma Modulator for Low-Power Audio Applications

Abstract

This paper presents a discrete-time fourth-order single-bit delta-sigma modulator for audio applications. The modulator is implemented in 0.18 um CMOS technology using fully differential switch-capacitor cascade of integrators feedback (CIFB) architecture. The modulator achieves a 112 dB peak Signal to Noise and Distortion Ratio (SNDR) in 20-kHz signal bandwidth with a sampling frequency of 5.12MHz. The power consumption of the proposed modulator core is 3.9 mW at a supply voltage of 1.8 V.