| 摘要 |
PURPOSE:To control stopping quickly and exactly, by producing the rotational frequency signal of a level according to rotational frequency, and by controlling the stopping based on the comparing output of a level comparator and a window comparator for setting said signal to be comparing input. CONSTITUTION:A disc 1 is rotationally driven by a spindle motor 2, and its recording informations are read by an optical pick-up 3. The read output of the pick-up 3 is fed to a video information demodulation system 5 and a digital information demodulation system 6 via an RF amplifier 4. The moving position of the pick-up 3 is detected by a detector 11, and is fed to a system controller 9. Besides, a rotational frequency detection circuit 13 is set, and this rotational frequency signal is fed to said controller 9 via a level comparator 14 and a window comparator 15. As a result, by the controller 9, the rotating direction of the motor 2 is discriminated, and it is discriminated that the motor is not in a stopping state, and the stopping of the motor 2 is controlled via a motor drive circuit 12.
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