Patent ID: 6919746

Claim:
A charge pump circuit for outputting a current in a period in accordance with an effective period in accordance with an input signal held at a first level in said effective period and held at a second level in a period other than said effective period, comprising: first and second transistors connected in series between a first power supply terminal and an output terminal of the charge pump circuit; a third transistor connected between a connection point of said first and second transistors and a second power supply terminal; and a control signal generation circuit, said control signal generation circuit generating a first control signal for turning said first transistor on in the period in accordance with said effective period and for turning off said first transistor other than this in accordance with said input signal and supplying the first control signal to the control terminal of said first transistor; generating a second control signal for turning said second transistor on earlier than said first transistor being turned on and turning off said second transistor later than said first transistor being turned off and holding a level where a desired output current flows when said second transistor is on and supplying the second control signal to the control terminal of said second transistor; and generating a third control signal for turning off said third transistor before said second transistor being turned on turning on said third transistor after said second transistor is turned off and supplying the third control signal to the control terminal of said third transistor.