To provide a power supply system wherein a semiconductor integrated circuit is effectively cooled and power can be supplied at the same time.

The semiconductor integrated circuit 12 is a flip chip of BGA (Ball Grid Array) structure, and is connected to a printed board 20 through solder balls 22. An electromotive cooling head 10 includes a substrate 40, a north-pole magnet 50, and a south-pole magnet 52, and is in tight contact with the semiconductor integrated circuit 12 so that it covers the rear face of the integrated circuit. The substrate 40 is provided with channels 42 of micro channel structure, and conductive fluid is let through the substrate. Positive poles 44 and negative poles 46 are provided so that they sandwich the channels 42 between them. Electromotive force Es is produced between the positive poles 44 and the negative poles 46 by the interaction of magnetic fields and the conductive fluid. The semiconductor integrated circuit 12 is provided on its rear face with a supply voltage terminal Vdd and a ground terminal GND, and is driven by the electromotive force Es produced in the electromotive cooling head 10.