Patent ID: 7795957
Filing Date: 2010-09-14
Classification: H03K

Abstract:
1. A power supply circuit for south bridge chip, comprising: a voltage conversion chip having a first voltage input terminal, a second voltage input terminal, a driving voltage output terminal, and a gate voltage output terminal; a control circuit having a first control terminal electrically coupled to the driving voltage output terminal, a second control terminal electrically coupled to the gate voltage output terminal, and an output terminal; and a filter circuit coupled between the control circuit and the south bridge chip; wherein the voltage conversion chip receives a first voltage and a second voltage from a power supply at the first and second voltage input terminals respectively, and outputs driving voltages at the driving voltage output terminal and gate voltage output terminal respectively, the control circuit receives the driving voltages at the first and second control terminals respectively, and outputs a working voltage to the south bridge chip via the filter circuit.