To prevent heating due to degradation in efficiency, without degrading the efficiency of power supply by providing a current reducing means for causing inrush current to disperse and reducing its value.

If a transistor Tr14 is turned off when an inrush current reducing circuit 10 is off, for example, an IC 16 starts comparing the collector voltage of the transistor Tr14 with a voltage set on the IC 16. When the collector voltage of the transistor Tr14 falls below the voltage set on the IC 16, the IC 16 can discharge capacitors C17, C18, and C19 in order to turn off transistors Tr11-Tr13. Thus, the inrush current reducing circuit 10 is provided with the transistors Tr11-Tr13 and the IC 16, which detects that the transistor Tr14 was turned on and exercises on-control of the transistors Tr11-Tr13. The transistors Tr11-Tr13, IC 13 and IC 16 function as a current-reducing means, which disperses inrush current and reduces its value.