Patent ID: 7768341
Filing Date: 2010-08-03
Classification: H02M

Abstract:
1. A semiconductor charge pump for two systems, comprising: a plurality of N-channel MOS (Metal Oxide Semiconductor) transistors which configure current rectifier elements, respectively, said plurality of N-channel MOS transistors having gates and being connected in series between an external supply power source and a voltage increase output power source; a plurality of first pumping capacitors one electrode of each of which is connected to a connection point of each of said plurality of N-channel MOS transistors; a clock signal generating circuit which generates first and second clock signals whose phases are different from each other by 180 degrees, the first and second clock signals being alternately supplied from the clock signal generating circuit to the other electrodes of said plurality of first pumping capacitors; a plurality of resistor elements connected to connection points of said plurality of N-channel MOS transistors at one end and connected to gates of said plurality of N-channel MOS transistors at the other end; and a plurality of second pumping capacitors one electrode of each of which is connected to the other end of each of said plurality of resistor elements, the first and second clock signals being alternately supplied to the other electrodes of said plurality of second pumping capacitors, thereby generating control signals which control gates of said plurality of N-channel MOS transistors, wherein, by means of the control signal generated by said plurality of second pumping capacitors in the semiconductor charge pump for one system, gates of said plurality of N-channel MOS transistors in the semiconductor charge pump for the other system are controlled.