| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor drive circuit capable of detecting the fact that the frequency of a control signal has changed into a state which indicates stoppage of the motor more quickly. <P>SOLUTION: Upon detecting the fact that the pulse output frequency of a control signal VTP has exceeded a predetermined threshold which is set in the high zone of a target value, an energization stopping unit 57 stops energization of the motor. A frequency detection unit 56 consists of a counter 61 which counts the output intervals of pulse edge of the control signal VTP, and the energization stopping unit 57 includes a comparator 68 which compares the count value VTP_data of the counter 61 with a data value corresponding to a threshold. <P>COPYRIGHT: (C)2010,JPO&INPIT |
