| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor drive circuit to detect an abnormality which does not carry a big change to a drive current of a motor. <P>SOLUTION: When a transistor Q3 is turned on by a drive pulse Pd output from a drive pulse generating circuit 13, a capacitor C1 provided between one terminal of the motor 1 and a ground line 5 is charged by current running through a winding of the motor 1. Comparators 15 and 16 compare a terminal voltage Vc of the capacitor C1 after charged with a first threshold voltage Vth1 and a second threshold voltage Vth2. A determination circuit 17 detects a change of an inductance of the winding of the motor 1 based on levels of output signals Sa and Sb of the comparators 15 and 16. <P>COPYRIGHT: (C)2010,JPO&INPIT |
