| 摘要 |
PURPOSE:To enable to brake a motor only by a motor drive signal by detecting the varied component when the motor drive signal is varied from the drive state to the stop state and controlling the signal by a switching circuit. CONSTITUTION:When a motor drive signal T1 becomes from low to high level, a transistor Q3 is turned ON to drive a motor M, and a transistor Q1 is turned ON to discharge a capacitor C2, thereby holding a transistor Q2 in OFF state. When a drive signal T1 becomes from high to low level, the Q3, Q1 are turned OFF, a pulse is generated by a differentiator which has the capacitor C2, a diode D1 and a resistor R3, the transistor Q2 is turned ON, and the brake current due to the counterelectromotive force of the motor M is flowed to stop the motor. Accordingly, the drive and the brake can be performed by one drive signal, thereby simplifying the circuit. |
