Circuit for supplying constant voltage

Abstract

A constant voltage supplying circuit including an output transistor is connected to a power source line and an output terminal. A base-emitter voltage of the output transistor is detected by a voltage detecting circuit composed of a transistor. A current-outputting circuit for supplying a current determined based on the voltage detected by the voltage detector to a reference voltage supplying circuit is used in the constant voltage supplying circuit. The reference voltage is supplied to a base of the output transistor to cancel a base-emitter voltage of the output transistor and to equalize the output voltage to a voltage generated in a reference voltage generating element included in the reference voltage supplying circuit. In this manner, the output voltage is kept constant notwithstanding variation of output current.

Dependencies are inferred from the claim text.