A low-noise phase-detector-based (PD-based) comparator is proposed for subrange analog-to-digital converters (ADCs) in this thesis. It can reduce the thermal-induced noise as well as the probability of the metastability. The 10-bit subrange ADC is composed of a 3.9-bit flash ADC and a 7-bit SAR ADC. The proposed ADC was fabricated in a 40-nm LP CMOS technology. The ADC achieves 54.41-dB SNDR at 160MS/s under a 1.1V supply voltage and consumes 2.7mW. The figure-of-merit (FOM) is 39.4 fJ/conversion-step. The active area is 0.0475 mm2.
