I. Introduction
Analog-to-digital converters play a key role in the growing semiconductors industry in the recent years. But with the increasing integration of components on the chip, demand for low power consumption and high speed ADC is being increased. Hence the designers these days meet the specifications through the innovations in the circuit design rather than reducing the transistor size or supply voltage as they pose serious problems on reliability. Comparators form the primary block of ADC that measure the smallest voltage differences in the inputs applied. So the performance and precision of any ADC depends on the comparator.