a high voltage operational amplifier receives a low voltage differential input signal at a low voltage transconductance stage which provides a differential current output . an intermediate stage has a differential current input coupled to the differential current output of the transconductance stage via a voltage buffer stage and produces a voltage output at a high voltage level but with low voltage swings providing a voltage representing the differential input signal . an interface stage is coupled to receive the voltage output of the intermediate stage and provides voltage and current outputs representing the voltage output of the intermediate stage . output sourcing and sinking stages receive the voltage and current outputs of the interface stage , respectively , and produce high currents representative of the differential input signal . the combination of the high current outputs of the output sourcing and sinking stages produces a high voltage output signal at the output terminal .