| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensorless motor driver which prevents reverse rotation of a motor. SOLUTION: Prior to starting a motor M, a starting portion 5 turns a switch SW1 on and turns a switch SW2 off, causes an updown counter 802 to start the count up operation, and subsequently turns the switch SW1 off at a falling edge of a signal A outputted from a comparator 801, and turns the SW2 on. Along with it, the starting portion 5 causes the updown counter 802 to start count down operation; and depending on whether or not the output value CNT of the updown counter 802 is zero subsequently at a falling edge of the signal A outputted from the comparator 801, which of a first phase coil L1 of and a second phase coil L2 of should be energized first to start the motor M is determined. |
