Patent ID: 6480057
Filing Date: 2002-11-12
Classification: H02M

Abstract:
A charge pump circuit transferring positive charge or negative charge of an input node to an output node in synchronization with a clock signal, for generating a voltage higher or lower than a power supply voltage, comprising:a first transistor of a first conductivity type connected between said input node and said output node; a second transistor of a second conductivity type connected between said input node and an input electrode of said first transistor; a first driving circuit pulling down or pulling up a potential of said input node by an amount of a predetermined first voltage during a first time period of each period of said clock signal; a first switching circuit turning said second transistor non conductive by connecting an input electrode of said second transistor and the input electrode of said first transistor during a second time period in said first time period and turning said second transistor conductive by supplying an activation potential to the input electrode of said second transistor during a time period other than the second time period; and a second driving circuit, turning said first transistor conductive by pulling up or pulling down a potential of the input electrode of said first transistor to adjust a potential difference between the input electrode of said first transistor and said input node so that the potential difference is larger than said power supply voltage during a third time period in said second time period and, transferring positive charge or negative charge of said input node to the output node.