Patent ID: 6703890
Filing Date: 2004-03-09
Classification: H02M

Abstract:
A voltage supply circuit provided withan oscillator circuit which outputs an oscillation signal having a prescribed frequency, a first comparator circuit which compares the oscillation signal with a prescribed reference signal and outputs a signal in accordance with the result of the comparison, a second comparator which sustains its output at a prescribed level when the amplitude of the output signal of the first comparator circuit is lower than a prescribed value and outputs a signal in accordance with the output signal of the first comparator circuit when the output signal of the first comparator circuit has exceeded the reference value, a buffer circuit which outputs a first driving current and a second driving current having inverted phases with respect to each other according to the output signal of the second comparator circuit, and a charge pump circuit having multiple capacitors to be charged alternately by the first and second driving currents and which outputs a voltage different from a source voltage.