A compact rail-to-rail output stage for CMOS operational amplifiers

Abstract

This paper presents a CMOS output stage devised for driving heavy resistive loads. An operational amplifier of this type has been fabricated in a 3 /spl mu/m double-polysilicon CMOS technology. With a supply voltage of /spl mnplus/5 V and load of 470 /spl Omega/, the amplifier has a /spl mnplus/4.6-V output swing and features a 60 mA short-circuit output current. Although simple, the proposed configuration enables the output transistors to be driven efficiently.