Offset voltage analysis of dynamic latched comparator

Abstract

The offset voltage of the dynamic latched comparator is analyzed in detail, and the dynamic latched comparator design is optimized for the minimal offset voltage based on the analysis in this paper. As a result, 1-sigma offset voltage was reduced from 12.5mV to 6.5mV at the cost of 9% increase of the power dissipation (152μW from 136μW). Using a digitally controlled capacitive offset calibration technique, the offset voltage of the comparator is further reduced from 6.50mV to 1.10mV at 1-sigma at the operating clock frequency of 3GHz and it consumes 54μW/GHz after the calibration.