| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor drive circuit which can stop a motor in case of failure, without generating erroneous stoppings, and is capable of surely preventing the motor and the driving part from being damaged by burning. SOLUTION: In this motor drive circuit, a burning preventive means which stops a motor, based on the magnitude of current flowing through a driving part 4 for applying current into the motor is constituted of first and second over-current detecting circuit 6, 7 for detecting that it has reached first and second over-current determination values, first and second over-current generating time determining circuit 8, 9 for determining that the period of an over- current generating condition detected by the first and the second over-current detecting circuits has reached first and second determination times, and a latch circuit 11 for inputting first and second motor stopping signals which are outputted by the first and the second over-current generating time determining circuits through an OR circuit 10. The first over-current determination value is set to be smaller than the second over-current determination value, and the first determining time is set to be longer than the second determining time. |
