| 摘要 |
PURPOSE:To enable the pull-in time of a phase controlling system to be shortened, by modulating a rotational speed according to the generating position of pulse signal showing rotary phase when the rotational speed is set to be almost constant. CONSTITUTION:The input of FG signal to a terminal 401, the input of reference signal to a terminal 402, and the input of H.SW signal to a terminal 403 are respectively provided. By input capture registers 404-406, at the time of the rise or the fall edge of the respective signals of the terminals 401-403, the count value of a counter circuit 407 is latched. A microcomputer 410 is composed of a central processing unit 411, a ROM 412, a RAM 413, and an interruption handling circuit 414. So far as the micro-computer 410 is concerned, by using a value latched by the respective input capture registers 404-406, arithmetic is performed on speed error signal and phase error signal, and both the signals are combined with each other, and after that, the signals are filter- processed, and its result is fed to a motor driving circuit via a D/A converter circuit 415. |
