In a basic circuit of a booster circuit, two charging units perform a charging operation and two boosting units perform a boosting operation (discharging operation). One of the charging units is connected to a voltage input and the other is connected to a voltage output. The charging unit that is connected to the voltage input includes three parallel connected MOS transistors Q11, Q12, and Q13, the other charging unit includes a MOS transistor Q4. One of the boosting units is connected to the voltage input and the other is connected to the voltage output. The boosting unit that is connected to the voltage input includes three parallel connected MOS transistors Q31, Q32, and Q33, the other boosting unit includes a MOS transistor Q2. Q11 and Q31 are turned ON immediately after start up, then Q12 and Q32 are turned ON and finally Q13 and Q33 are turned ON.