| 摘要 |
PURPOSE:To remove a loss at the time of overload state and to utilize a small- sized and economical power supply transformer at its maximum by detecting the overload state of a constant voltage circuit and controlling a switching circuit so as to be closed state during the output of the overload detecting signal. CONSTITUTION:The load consumption current of a load such as a power amplifier connected to output terminals 15, 16 is increased and exceeds a prescribed level, voltage drop by a power supply transformer 17, a rectifier circuit 18, etc. is increased, so that the output voltage of a constant voltage circuit 11 can not be kept at a prescribed constant voltage value, the interrupted state of the voltage value, i.e. the overload state, is detected by a detecting circuit 13 and a driving circuit 14 turns the switching circuit 12 to the closed state on the basis of said overload detecting signal. Consequently, the circuit 11 is shorted and a power supply circuit 10 is directly connected to the circuit 18, so that a power loss in the circuit 11 is removed and the maximum current is efficiently supplied to the load. |
