| 摘要 |
PURPOSE:To avoid malfunction due to a short time rush current caused by surge or the like and to allow the user to recognize a cause of interrupting the power supply circuit by lighting an LED. CONSTITUTION:When an error takes place in a flyback transformer 5 or its load side and a current flowing to a resistor 3 increases and a transistor(TR) 6 is active, a current flows to a resistor 7 and a terminal voltage of the resistor 7 reaches a threshold level or over. A CPU 13 brings a level of a terminal B to a low level, when the state of an output of an A/D converter 11 larger than the threshold level continues longer than a prescribed time, to deenergize a relay 8 and brings a level of a terminal C to a high level to turn on a TR 21 and to light an alarm LED 22. |
