Patent ID: 7382180

Claim:
A voltage source circuit having a reference voltage output terminal, comprising: an amplifier having a positive input terminal, a negative input terminal, and an output terminal, wherein the positive input terminal receives an operating voltage; a first current mirror circuit having a first current terminal and a second current terminal, wherein the first current terminal is electrically coupled to a driving current for duplicating the driving current to the second current terminal; a first PMOS transistor having a drain that is grounded, a gate is electrically coupled to the output terminal of the amplifier, and a source is electrically coupled to the second current terminal of the first current mirror circuit; an NMOS transistor having a source that is grounded through a first resistor and electrically coupled to the negative input terminal of the amplifier, and a gate is electrically coupled to the second current terminal; and a second current mirror circuit having a third current terminal and a fourth current terminal, in which a current flowing through the third current terminal is duplicated to the fourth current terminal, wherein the third current terminal is electrically coupled to the drain of the NMOS transistor, and the fourth current terminal is grounded through a second resistor and electrically coupled to the reference voltage output terminal.