A 98.5-dB DR Incremental ΔΣ ADC with Dynamic Zoom and Extended Counting
for Audio Application
Abstract
A three-step discrete-time incremental analog-to-digital converter
(IADC) combines zoom, IΔΣM and dual-mode SAR-assisted extended counting
(EC). The IADC reuses the SAR ADC to reduce hardware cost by
reconfiguring its DAC array to either a 2-bit quantizer of the core IΔΣM
or a 5-bit EC ADC. Clocked at 4MHz with an OSR=99, the proposed IADC
achieves SNDR and DR of 93dB and 98.5dB, respectively, in a BW of
20.2kHz.