| 摘要 |
PURPOSE:To attain the diagnosis of deterioration without taking off a operational amplifier for diagnosis object from a printed board by comparing two power current signals supplied to the operational amplifier for diagnosis object and comparing the output signal from a comparator and comparison reference. CONSTITUTION:An oscillator 2 is connected with the operational amplifier 1 for deterioration diagnosis object, and a computing element 7 operates a difference between the value 11 of an ammeter 3 measuring the power current on a plus side and the value 12 of an ammeter 4 measuring the power current on a minus side. A comparison reference setting unit 8 evaluates the difference between the power current value on the plus side of the normal operational amplifier and the source current value on the minus side, and previously sets comparison reference for deterioration decision. The comparator 9 compares the difference between the source current value on the plus side and the source current value on the minus side obtained from the computing element 7 and comparison reference outputted from the comparison reference unit 8, and a display device 10 displays the compared result of the comparator 9. Thus, deterioration diagnosis is attained without taking off the operational amplifier 1 for diagnosis object from the printed board. |
