Constant voltage circuit

Abstract

A constant voltage circuit comprises first and second circuit terminals; a current source connected to said first and second circuit terminals; a first npn transistor whose collector is connected to the first circuit terminal through a resistor; a second npn transistor having a collector connected to the emitter of the first npn transistor, a base connected to the collector of the first npn transistor, and an emitter connected to the second circuit terminal; a third npn transistor having a base connected to the base of the first npn transistor, an emitter connected to the emitter of the first npn transistor through a resistor and a collector connected to the first circuit terminal through a resistor; a fourth transistor having a base connected to the collector of the third transistor and a collector and emitter coupled to the first and second circuit terminals; a resistor connected between the first circuit terminal and a junction of the bases of the first and third transistors; and a resistor connected between the second circuit terminal and a junction between the bases of the first and third transistors.

Dependencies are inferred from the claim text.