摘要 |
One terminal 3a of the DC motor 3 is connected to the power supply terminal 301, and the other terminal 3b of the DC motor 3 is connected to the ground terminal 302 through the FET 1. The FET 2 is connected between the terminal 3a and terminal 3b of the DC motor 3. A reversal input terminal of the comparator 6 is connected to the terminal 3a of the DC motor 3, and a non-reversal input terminal of the comparator 6 is connected to the terminal 3b of the DC motor 3. The output terminal of the comparator 6 is connected to the gate of the FET 2 through the switch SW1. The CPU 200 supplies a control signal FV which is changed at a predetermined period T according to the speed signal supplied from the receiver 100, to the gate of the FET 2 through the driver 7. When the counter electromotive force is generated in the DC motor 3, the comparator 6 supplies a high level control signal RD to the gate of the FET 2 through the switch SW1. <IMAGE> |