摘要 |
There are provided upper and lower switching elements 1U to 1W and 2U to 2W for energizing motor drive windings 4U to 4W, a control circuit 20 that starts outputting a control signal for energization based on an energization instruction, pre-drive circuits 8U to 8W and 9U to 9W for controlling ON/OFF of the upper and lower switching elements based on the control signal, and short circuit detection circuits 10U to 10W for detecting short circuits in a node 14 between the upper and lower switching elements to higher-potential and lower-potential power sources based on the control signal and a voltage of the node. The short circuit detection circuits are controlled to detect a short circuit in the node to the lower-potential power source with all the upper switching elements turned ON and all the lower switching elements turned OFF and to detect a short circuit in the node to the higher-potential power source with all the upper switching elements turned OFF and all the lower switching elements turned ON, in a state where the motor drive windings are not energized. It is possible to prevent a situation in which a short circuit cannot be detected depending on a resistance component of a drive target.
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