A power source circuit includes a power source wiring at a high potential
side provided with a first power source voltage and a second power source
voltage, a power source wiring at a low potential side and booster
circuit as a charge pump installed between the power source wiring at a
high potential side and the power source wiring at a low potential side
and provided with a plurality of switching transistors and a plurality of
capacitors. A control device is provided for controlling the booster
circuit. A predetermined number of power sources includes the power
source wiring at the high potential side are further provided with the
power source circuit. An input voltage is selectively input to a part of
the booster circuit from any one of the predetermined number of power
sources. The control device fixes all of the switching transistors
inputting the predetermined number of power sources except one of the
switching transistors and the control device controls the booster circuit
to implement a boosting operation by switching the switching transistor
not fixed with a predetermined frequency and a predetermined phase
relationship so as to switch the input of the predetermined number of
power sources and selectively output a predetermined number of output
voltages from the booster circuit.