20.2 A 40MHz-BW 320MS/s Passive Noise-Shaping SAR ADC With Passive Signal-Residue Summation in 14nm FinFET

Abstract

SAR ADCs are popular in mobile WiFi applications due to their low power and small area. SNR of 60-70dB is necessary to meet the noise budget for the downlink chain in the 802.11 ac/ax standards. Comparator noise and quantization noise are typically the dominant noise sources limiting the SNR. Recently, noise-shaping SAR (NS-SAR) ADCs have become popular to increase SNR by reducing these two noise sources through noise shaping.