Analysis of CMOS Comparator in 90nm Technology with Different Power Reduction Techniques

Abstract

To reduce power consumption of regenerative comparator three different techniques are incorporated in this work. These techniques provide a way to achieve low power consumption through their mechanism that alters the operation of the circuit. These techniques are pseudo NMOS, CVSL (cascode voltage switch logic)/DCVS (differential cascode voltage switch) & power gating. Initially regenerative comparator is simulated at 90 nm CMOS technology with 0.7 V supply voltage. Results shows total power consumption of 15.02 μW with considerably large leakage current of 52.03 nA. Further, with pseudo NMOS technique total power consumption increases to 126.53 μW while CVSL shows total power consumption of 18.94 μW with leakage current of 1270.13 nA. More then 90% reduction is attained in total power consumption and leakage current by employing the power gating technique. Moreover, the variations in the power consumption with temperature is also recorded for all three reported techniques where power gating again show optimum variations with least power consumption. Four more conventional comparator circuits are also simulated in 90nm CMOS technology for comparison. Comparison shows better results for regenerative comparator with power gating technique. Simulations are executed by employing SPICE based on 90 nm CMOS technology.