| 摘要 |
A drive device (10) for a brushless motor (2) executes an abnormality diagnosis (disconnection/short-circuit) of a motor side circuit. In detecting abnormality of the motor side circuit, the drive device includes a terminal voltage monitor circuit (16) that monitors a terminal voltage of an output terminal (Drv) that is connected to a motor terminal of respective phases (U, V and W). A microcomputer (20) starts abnormality diagnosis under a condition where the motor is stopped, and an object to be driven has normally operated at the time of driving the motor. For executing the abnormality diagnosis, the microcomputer (20) turns on/off only a transistor (Tr1) of the drive circuit of one phase in a state where all of transistors (Tr1 and Tr2) are turned off, and acquires monitor signals to execute the abnormality diagnosis based on signal levels of the monitor signals. |
