| 摘要 |
<p>PURPOSE:To enable to accurately control the speed of a motor even if the rotating speed of the motor varies by obtaining a clock for detecting the phase applied to a counter type phase detector and a reference phase signal from the outputs of the same variable frequency oscillators. CONSTITUTION:The output of a variable frequency oscillator 31 is used as a clock 40 for detecting a phase, and applied to a 1/N frequency divider 32 to become a reference phase signal 39. A counter 33 counts the clock 40 after cleared at the leading edge of the signal 39. On the other hand, a latch circuit 34 latches the output of the counter 33 at the leading edge of a tack pulse 41 generated from an encoder 38 to detect the phase difference between the signal 39 and the pulse 41. The output of the circuit 34 is supplied to a motor drive 36 through a D/A converter 35.</p> |
