A complementary fully differential dynamic comparator with insensitive common-mode mismatch

Abstract

This study provides a theoretical basis and technical guidance for the design of fully differential dynamic comparators to make the offset insensitive to common-mode mismatch. A fully differential dynamic comparator with complementary inputs is proposed. And a metric called Common-Mode Mismatch to Imbalance Ratio (CMMIR) is also presented for evaluating how much the common-mode mismatch affects the offset. Simulation results indicate that the CMMIR of the proposed comparator has a reduction from 2 to 0.1845 with a 100mV common-mode mismatch relative to the CMMIR of conventional ones.