POWER SUPPLY CIRCUIT

PROBLEM TO BE SOLVED: To provide a power supply circuit comprising a stand-by power supply circuit that is low in cost and has a high degree of freedom of design on a safety standard. SOLUTION: The power supply circuit 10 is provided with a primary winding 2 that is wound on an iron core 3 of a power supply transformer 1 for supplying electric power to an electric appliance. An inductor 9 is connected in series to the primary winding 2, and a relay switch 8 that is interlocked with a part of power supply switches of a power-supplied electric appliance is connected in parallel to the inductor 9 to give AC power e to the primary winding 2. A rectifier circuit 5 comprising a diode is connected to a secondary winding 4 wound on the iron core 3. The rectifier circuit 5 outputs electric power as a power amplifier power source Va as it is, supplies power as other various kinds of power sources Vb via a stabilizing circuit 7, and further supplies power as a microcomputer power source Vc via another stabilizing circuit 6. The current limiting action of the inductor cuts power consumption in a stand-by state. COPYRIGHT: (C)2004,JPO&NCIPI