摘要 |
PROBLEM TO BE SOLVED: To provide a circuit device capable of securely protecting a switch from counter electromotive voltage generated in cutting off an inductive load, and a power supply system comprising the circuit device.SOLUTION: A circuit device 1 includes: a conductive fixation unit 12 securely fixed, by a screw N1 for example, to a conductive body 19 to securely form a flow back route for preventing high voltage from being applied to both ends of an FET 6 functioning as a switch by flow back current, in the case that counter electromotive force is generated across both ends of an inductive load 3 by the FET 6 having switched from On to Off; an electric potential difference detection unit 10 for detecting electric potential difference between an output terminal of a regulator 9 and an end 18 of a branch electrification route 17; and a micro computer 8 for determining whether or not the fixation unit 12 is grounded on the body 19, by determining whether or not the detected electric potential difference is lower than a threshold. When it is determined that the fixation unit 12 is not grounded, a notification device 14 notifies a driver of a vehicle or the like. |