1. A transconductance amplifier, comprising: An input amplifier stage; an output amplifier stage; and a replica output stage which generates a feedback current which is a scaled replica of the output current of the amplifier, wherein the feedback current is provided to the amplifier input; and wherein the input amplifier stage comprises a first inverter and a second inverter in series, the second inverter providing a drive signal, and the amplifier output stage and replica output stage are driven in parallel each by the drive signal.