Offset Voltage Reduction Methods for a Two-Stage Folded Cascode Operational Amplifier

Abstract

Low voltage operational amplifiers design uses diverse innovative techniques for increasing their performance. Offset voltage is a key parameter that must be constantly reduced. Two-stage folded cascode using a differential input stage and an AB class output stage is an advanced design solution in CMOS technology. This paper focuses the offset voltage of this type of operational amplifier and highlights mutual transconductance and threshold voltage as important factors that can be used to minimize the offset voltage as much as possible. Distinct reduction methods for this important parameter are also established.