Patent ID: 8884659

Claim:
A load driving device for driving a resistive load including a first end being grounded and a second end, the load driving device comprising: a pulse driving circuit which has an output terminal connected to the second end of the resistive load, is configured to repetitively apply a pulse voltage to the resistive load, and includes a capacitor disposed between the output terminal and a ground potential; a level detection circuit configured to detect whether an output terminal voltage on the output terminal of the pulse driving circuit is at high level or at low level; a switching discharge unit which forms a discharge path through which electric charges charged in the capacitor are discharged by switching a switch from a non-discharge side to a discharge side, wherein when disconnection occurs in a connection path between the pulse driving circuit and the resistive load in a state where the application of the pulse voltage by the pulse driving circuit stops and the output terminal voltage is maintained at the high level, the switching discharge unit switches the switch to the discharge side over a discharge maintenance time sufficient to change the output terminal voltage from the high level to the low level; a post-discharge detection unit configured to detect the level of the output terminal voltage by the level detection circuit after the switch returns to the non-discharge side; and a determination unit configured to determine the occurrence of disconnection in the connection path when the post-discharge detection unit detects the low level and determine the occurrence of short-circuiting of a first connection path connecting the output terminal and the second end of the resistive load to a power supply potential when the post-discharge detection unit detects the high level.