| 摘要 |
PURPOSE:To surely tune the rotational speed of a motor to the frequency of a motor by generating a brake signal to control a motor in the case where plural pieces of FG pulses exist within half cycle of a reference clock. CONSTITUTION:Fg pulses 100, which are led out of a motor according to the rotation of a motor, and reference clocks 25 are given to a phase comparator 10. The output of the phase comparator 10 controls the rotational speed of the motor M through an integration circuit 30 and a motor driver 40. A brake signal generating circuit 200 consists of a D flip-flop (DFF) 1, DFF 2, DFF 3, and inverts G1 and G2, generates a brake signal 250 and gives it to the motor 40, in the case where plural pieces of FG pulses exist within half cycle of the reference clock 25. The motor driver 40 lowers the rotational speed of the motor M regardless of the output from the phase comparator 10 if there is a brake signal 250. |
