Patent ID: 6236394
Filing Date: 2001-05-22
Classification: G09G

Abstract:
A power supply circuit for converting a voltage and for supplying the converted voltage as a power supply voltage, said power supply circuit comprising:at least one charge pump circuit which includes a first capacitor, a second capacitor, a first switching means for charging said first capacitor based on a given voltage, and a second switching means for transferring the charge in said first capacitor to said second capacitor; anda switching signal generation circuit for generating a plurality of switching signals which control said first and second switching means;wherein said first switching means includes a plurality of switching elements, one ends of said switching elements being electrically connected to different potentials, and the other ends thereof being electrically connected to at least one end of said first capacitor; andwherein said switching signal generation circuit receives at least one given first control signal for controlling at least one of a boosting ratio and a boosting ratio, and then generates said switching signals for controlling ON and OFF-states of one of said switching elements specified by said first control signal, and for turning off at least one other switching element.