An unnecessary through current is suppressed and insufficiency of an output electric potential and increase in power consumption are suppressed in a power supply circuit using a charge pump method. In order to suppress a reduction in an output electric potential VPP as well as suppressing transient through currents I1 and I2 when a clock DCCLK is inverted, resistances R1 of a wiring 11, R2 of a wiring 12 and R4 of a wiring 14 are set so as to satisfy relations R4>R1 and R4>R2. That is, the through currents I1 and I2 can be suppressed by reducing the resistances R1 and R2 so that electric potentials V1 and V2 are quickly inverted when the clock DCCLK is inverted. Also, the through current I1 can be suppressed to suppress the reduction in the positive output electric potential VPP by setting the resistance R4 to be larger than either of the resistances R1 and R2.