Implementation of high performance operational transconductance amplifiers using graded-channel SOI nMOSFETs

Abstract

This paper presents the performance of operational transconductance amplifiers (OTAs) fabricated with Graded-Channel (GC) SOI nMOSFETs at room temperature. Different design targets were taken in account such as similar power dissipation, transconductance over drain current ratio and die area. Comparisons with high voltage gain and high unit voltage gain frequency OTAs made with conventional SOI nMOSFETs are performed showing that the GC OTAs present larger open-loop voltage gain without degrading unit voltage gain frequency, the phase margin, and slew rate with a significant required die area reduction depending on used LLD/L ratio. Experimental results and SPICE simulations are used to validate the analysis.