CURRENT MODE ADC USING CURRENT DIFFERENCING TRANSCONDUCTANCE AMPLIFIER

Abstract

This dissertation presents the implementation of a two bit flash analog‐to‐digital converter based on current‐mode technique. The analog‐to‐digital converter presented here employs three current differencing transconductance amplifier (CDTA) based comparator ,a current mirror and a priority encoder. The advantages of current ‐mode technique are higher speed, lower power dissipation, and simple division of reference current based on current mirror. The new method allows effective and simple high‐speed A/D conversion where the input is a current signal and the output is a digital voltage signal. By using this technique we have reduced the power dissipation and response time. This current mode method is highly accurate. The circuit has been simulated using the PSPICE simulator for .18 m CMOS technology with 1.8V supply to get satisfactory output.