| 摘要 |
PROBLEM TO BE SOLVED: To provide a fault detector for a drive circuit which can specify the faulty section of the drive circuit and can enhance the maintainability of the drive circuit. SOLUTION: This detector is equipped with a main relay RLY whose contact is connected to external power source Vin, a transistor Q3 which turns on or turns off the contact of the main relay RLY at power ON, a drive circuit 25 which has a power terminal 27 connected to the other contact of the main relay RLY and drives a motor M (load apparatus) connected to an output terminal 33 and an output terminal 35 lower in potential than the output terminal 33, and a capacitor C1 which is connected between the power terminal 27 and the output terminal 35, and this detects the voltage applied to the power terminal 27 by means of an external power voltage monitor circuit 37, and diagnoses the fault in the drive circuit 25, based on the voltage of the power terminal 27, when the transistor Q6 is turned on/off at power ON by means of the main relay control circuit 23. |
