A 47.5MHz BW 4.7mW 67dB SNDR Ringamp Based Discrete-Time Delta Sigma ADC

Abstract

This work presents a discrete-time (DT) delta sigma modulator (DSM) ADC that uses ring amplifiers to relax critical speed and efficiency bottlenecks. The DSM is designed as a 3rd-order Cascade of Integrator with Feed Forward (CIFF) with a 4-bit quantizer, and it achieves a peak SNDR of 67dB and DR of 70.0dB with 47.5MHz bandwidth when clocked at 950MHz. This is the highest bandwidth reported to-date among single-channel DT DSM ADCs and demonstrates a viable alternative to continuous-time (CT) DSM ADCs for wideband oversampling applications. With a power consumption of 4.7mW from a 1V supply, FOMs and FOMw are 167.0dB and 27.0fJ/c.s. respectively, demonstrating efficient DT delta-sigma conversion with high bandwidth.