| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor drive device capable of accurately detecting disconnection with no increase of dark currents. <P>SOLUTION: A disconnection determination circuit 13 compares an output voltage Vm, detected at a common connection point of both of a motor 8 and a P channel MOSFET 7, with a first threshold value Vth1 when the motor 8 is high-side driven by the P channel MOSFET 7, and if it is determined that the output voltage Vm does not change according to a PWM signal, the circuit stops outputting of the PWM signal. If the output voltage Vm, which is detected under such condition as a switch 11 of a serial circuit connected parallel to the motor 8 is closed, shows change to go below a second threshold value Vth2, it is determined that a disconnection has occurred. <P>COPYRIGHT: (C)2013,JPO&INPIT |
