| 摘要 |
PROBLEM TO BE SOLVED: To prevent the power supply voltage from rising by the brake function of an H bridge, and to prevent device breakdown due to the brake function, in a motor drive circuit of H bridge configuration.SOLUTION: A control unit 210 detects the rotational speed of a motor 400 when it is rotated by an external force, turns a brake enable signal on if the rotational speed of the motor 400 is equal to or lower than a predetermined threshold, otherwise turns a brake enable signal off. When the brake enable signal is on, a motor control voltage generation circuit 220 turns the transistors Q3, Q4 of a motor drive circuit 300 on and brings the motor 400 into brake state. When the brake enable signal is off, the transistors Q3, Q4 are turned off, and the motor 400 is released from the brake state. |
