STUDY AND IMPLEMENTATION OF COMPARATOR IN CMOS 50NM TECHNOLOGY

Abstract

This paper describes the comparator circuits used in FLASH Analog to digital converter (ADC). The performance of FLASH ADC is greatly influenced by the choice of comparator. In this paper, first a single ended “Threshold Inverter Quantizer” (TIQ) is presented. The TIQ comparator is based on a CMOS inverter cell, in which voltage transfer characteristics (VTC) are changed by systematic transistor sizing. However, TIQ comparator is very sensitive to power supply noise. Another comparator circuit presented in this paper is “Two stage open loop comparator”. It is implemented in 50 nm CMOS Technology. Pre-simulation of comparator is done in LT-Spice and post layout simulation is done in Microwind 3.1.