A 9.1 ENOB 21.7fJ/conversion-step 10b 500MS/s single-channel pipelined SAR ADC with a current-mode fine ADC in 28nm CMOS

Abstract

A single-channel 10b pipelined SAR ADC with a gm-cell residue amplifier and a current-mode fine SAR ADC achieves a 500MS/s conversion rate in a 28nm CMOS process under a 1.0 V supply. With background offset and gain calibration, the prototype ADC achieves an SNDR of 56.6dB at Nyquist. With power consumption of 6mW, it obtains a FoM of 21.7fJ/conversion-step.