Patent ID: 6323721
Filing Date: 2001-11-27
Classification: G05F,G11C,H02M,H03B,Y02B

Abstract:
A power supply circuit coupled to a first voltage, a second voltage, and a control voltage, said power supply circuit comprising:a plurality of MOS transistors serially coupled between the first voltage and the second voltage, wherein said plurality of MOS transistors comprises both PMOS and NMOS transistors,wherein one of said plurality of MOS transistors is switchable in response to the control voltage, has a first current flowing terminal coupled to another of the plurality of MOS transistors, a second current flowing terminal coupled to the second voltage, and a control terminal coupled to the control voltage, andwherein the power supply circuit is configured to generate a third voltage at an output node when the control voltage is above a selected value and to generate a fourth voltage at the output node when the control voltage is below the selected value.