A 80dB DR 6MHz Bandwidth Pipelined Noise-Shaping SAR ADC with 1–2 MASH structure

A pipelined NS-SAR ADC with 1-2 MASH structure is presented. Two-stage pipelined structure consisting of 5-bit NS-SAR and 4-bit NS-SAR ADCs shows 3 ^rd -order noise-shaping. To maximize power efficiency, a single operational transconductance amplifier (OTA) is reused for both an integrator for noise shaping and a residue amplifier for pipelining. The measured DR is 80dB when the sampling rate is 83.3MS/s and bandwidth is 6MHz, and power consumption is 3.5mW showing FoM _s,DR of 172.3dB. The proposed ADC structure greatly relaxes design requirement of each SAR quantizer, and can achieve high resolution and wide bandwidth with good power efficiency.