PURPOSE: To stabilize a regulated output voltage from a switching regulator, by providing a plurality of regulating circuits for generating a voltage, and making individual setting for phases of the voltage in each regulating circuit.

CONSTITUTION: Each switching regulator 10, 20 or 30 has a plurality of regulating circuits for each voltage, and these regenerating circuits generate the same voltage. As an example, the switching regulator 10 is made up of a regulating circuit 10A and a regulating circuit 10B for generating the same voltage V10a or V10b to fed the output to a circuit 2. The phase of voltage to the switching regulator 10, 20 or 30 is adjustable by controlling the phase of a control voltage in each regulating circuit so that an input current in the synthesized state from a master power source can be smoothed. Then, a variation 10 point voltage from the master power supply is reduced, while the stability in output voltage from the switching regulator is improved. At the same time, the input current is averaged uniformly and a rated value of a fuse can be reduced.