| 摘要 |
PURPOSE:To provide a circuit actuating a protection circuit under a prescribed overload with respect to a variable power supply applying an output voltage corresponding to a signal of various horizontal synchronizing frequencies in a wide input to a horizontal deflection circuit. CONSTITUTION:The circuit is provided with a voltage detection section 7 detecting an input voltage, a voltage detection section 6 detecting a voltage proportional to an output voltage of a signal of a horizontal synchronizing signal frequency, and a current detection section 5 detecting a current proportional to an output current, and the protection circuit is operated under a prescribed overload state by the product between the detected voltage and the detected current. Thus, in the case of a variable power supply whose output voltage changes depending on a horizontal synchronizing signal frequency in a wide input, the protection circuit is operated under a prescribed overload at all times even when the horizontal synchronizing signal frequency, that is, the output voltage changes. Furthermore, since the current detection section 5 is provided almost to a stabilized power supply circuit used widely at present, the protection circuit is used by having only to add voltage detection sections 6, 7 to the power supply circuit. |
