Patent ID: 6960949

Claim:
A charge pump circuit for outputting a current in 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, wherein said control signal generation circuit: generates a first control signal for turning said first transistor on in 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, generates a second control signal for turning said second transistor on before said first transistor is turned on, turning off said second transistor after said first transistor is turned off, 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 generates a third control signal for turning off said third transistor before said second transistor is 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, and wherein said first, second and third control signals are generated by said control generation circuit in accordance with a preliminary input signal having a phase advanced from said input signal.