A voltage generation circuit includes a voltage detection circuit that generates a detection voltage according to an output voltage, a reference voltage generation circuit that generates a reference voltage which changes periodically, a comparison circuit that generates a control signal according to a result of a comparison between the detection voltage and the reference voltage, wherein control pulses each having a pulse width according to the detection voltage are sequentially appeared in the control signal, and a driving pulse generation circuit that generates a driving pulse corresponding to the control pulse and supplies the generated driving pulse to a transistor connected to a DC power source when the pulse width of the control pulse exceeds a predetermined width, and stops generating the driving pulse when the pulse width of the control pulse becomes smaller than the predetermined width.