Patent ID: 6366071
Filing Date: 2002-04-02
Classification: G05F

Abstract:
A voltage control circuit including a bandgap reference circuit, comprising:a proportional to absolute temperature (PTAT) current source which provides a PTAT current; a proportional to base to emitter voltage (PTVBE) current source which provides a PTVBE current; said PTAT current source and said PTVBE current source coupled to a junction REF; said PTAT current source operably controlled by a first current source providing a current proportional to the ratio of the difference of the base to emitter voltage (&Dgr;VBE) of a first transistor and a second transistor coupled to a first resistive means in said first current source; said PTVBE current source operably controlled by a second current source providing a current proportional to the ratio of a base to emitter voltage (VBE) of a third transistor and a second resistive means in said second current source; a resistive means RX coupled between said junction REF and a reference potential, said resistive means RX configured to receive said PTAT current and said PTVBE current and in accordance therewith provide a reference voltage VREF at said junction REF which is essentially constant over temperature and which is proportional to a silicon bandgap voltage, said reference voltage VREF proportional to a said bandgap voltage of silicon (VBG) multiplied by the ratio of said resistive means RX and said second resistive means in said second current source; and said voltage control circuit operable with a voltage supply providing a voltage equal to the sum of said voltage VREF and a voltage drop across said PTAT current source.