| 摘要 |
PURPOSE:To improve the rise of rotation on start, by setting the output of a differential integrating circuit changing according to frequency difference between reference pulse and rotation detecting pulse, to be bias, and by finding the integration value of a phase error between the reference pulse and the rotation detecting pulse. CONSTITUTION:From a charge pump IC-1, the output of pulse signal according to a phase error between reference pulse and rotation detecting pulse is generated. By an integrating circuit IC-3, the output pulse of the charge pump IC-1 is integrated and is applied to the base of a transistor Q3 to control the driving current of a motor 10. In the meantime, from a charge pump bias circuit IC-2, the output of difference signal between the integration value of the reference pulsa and the integration value of the rotation detecting pulse is directed as bias signal to the positive terminal of the integrating circuit IC-3. As a result, rise on start is improved. |
