| 摘要 |
PROBLEM TO BE SOLVED: To suppress the increase in size of a circuit, in a device for determining deterioration of a photocoupler to which a predetermined AC voltage is applied.SOLUTION: A device 42 for determining deterioration of a photocoupler 30 which outputs a pulse signal according to an applied predetermined AC voltage determines that the photocoupler 30 is deteriorated when a duty ratio of the pulse signal is smaller than a determination value. |
