| 摘要 |
PURPOSE:To simply control a motor by utilizing a demodulated clock signal synchronized with a data signal and comparing it with a reference signal. CONSTITUTION:A data signal detected by a pickup 1 is supplied through an amplifier 3, a waveform shaper 4 to a demodulator 5 and a demodulating clock signal generator 6. The output of the generator 6 is inputted to a phase comparator 8, the output from the reference oscillator 9 is compared in phase, the error voltage is supplied through a low pass filter 10 to a motor drive circuit 11, thereby controlling the rotating speed of the motor 10. The demodulator 5 detects the length of the data signal on the basis of the demodulation clock, and binary data is outputted in response to the length of the data signal. |
