Voltage follower circuit

Abstract

A voltage follower circuit is comprised of a plurality of transistors. A first transistor has a base connected to an input terminal and a collector connected to a positive power source terminal. A second transistor of opposite polarity relative to the first transistor has an emitter connected to the emitter of first transistor, and a collector and a base coupled to each other. A third transistor of opposite polarity relative to the first transistor has a base connected to the base of second transistor. A fourth transistor has an emitter connected to the emitter of third transistor, and a collector and a base coupled to each other. A current source is connected at its one end to the first power source terminal and connected at its other end to the collector of fourth transistor. A current mirror circuit is connected at its output port to the collector of second transistor and connected at its input port to the collector of third transistor.

Dependencies are inferred from the claim text.