Patent ID: 7224208
Filing Date: 2007-05-29
Classification: G05F

Abstract:
1. A voltage regulator which generates a predetermined direct-current voltage, comprising: a first electrical source terminal which receives a first electrical source voltage; a second electrical source terminal which receives a second electrical source voltage which is lower than the first electrical source voltage; a reference voltage generator, coupled between the first electrical source terminal and the second electrical source terminal, that outputs a reference voltage based on the first and second electrical source voltages; an output circuit, coupled between the first electrical source terminal and the second electrical source terminal, that generates the predetermined direct-current voltage based on the reference voltage and that generates a comparison voltage lower than the predetermined direct-current voltage; a differential amplifier, coupled between the reference voltage generator and the output circuit, that provides a control voltage to the output circuit responsive to a difference between the reference voltage and the comparison voltage; and a voltage adjustment circuit, coupled to the reference voltage generator and the differential amplifier, that adjusts the reference voltage responsive to a variation in the first electrical source voltage, wherein the voltage adjustment circuit includes