Comparative analysis of CMOS circuits of a thermometer-to-binary encoder for integrated flash analog-to-digital converters

Abstract

The speed of a flash analog-to-digital converter (ADC) is limited by both the comparator response time in the input analog part of the circuit and the delay time of the encoder that converts the thermometer code on the comparator outputs into the output straight binary code. In this paper, we consider the problems of the synthesis of CMOS circuits of encoders for integrated flash ADCs. New encoder circuit designs with a reduced delay are proposed. The comparative analysis of the main characteristics of CMOS circuits of encoders based on the data of circuit simulation for the 180 nm MOSFET technology is presented.