9.5 A 118.5dBA DR 3.3mW Audio ADC with a Class-B Resistor DAC, Non-Overlap DEM and Continuous-Time Quantizer

Applications requiring far field voice/audio recording have increased the need for low-power, high dynamic range (DR) audio ADCs. In these applications, the DR specification determines the maximum distance at which a low-cost microphone can obtain a good quality recording. THD + N (SNDR) is not as important as it is limited by the microphone performance. CTDSMs are chosen for audio applications due to inherent anti-aliasing and resistive input. This work presents a high-performance audio CTDSM designed in a 130nm process. The ADC achieves a DR of 118.5dB A-weighted (116.3dB un-weighted) over 20Hz-20kHz bandwidth while consuming only 3.3mW.