| 摘要 |
PURPOSE:To attain formation of LSI (large scale integration) by converting a reproduction output, which is obtained from servo signal blocks at both right and left sides and exceeds the prescribed level, into a pulse form, and forming a position error signal from the difference of the number of pulses between output pulse trains corresponding to the reproduction output. CONSTITUTION:After a control signal 28 positions approximately a track, the output 22 of a magnetic head assembly 12 is supplied to a data discrimination circuit 19 and a voltage comparator 15 through an amplifier 14. The comparator 15 compares the output of the amplifier 14 with a reference voltage 24 indicated by a pulse counting control circuit 16, converts only a reproduction output waveform which exceeds the voltage 24 into a pulse and transmits it as a pulse train 23 to the circuit 16. The circuit 16 finds to position of the servo signal block from the output 26 of a rotary position detector 18 of a magnetic disk 11, separates the pulse caused by the servo signal block from the pulse train 23, detects the number of pulses and forms the track position error signal 27. Thus an electronic circuit can be made an integrated circuit, and LSI formation of a device can be attained. |
