JPH05282639A - Method for recording tracking error detection signal and device for detecting tracking error - Google Patents

Abstract

PURPOSE:To obtain a high-accurate tracking error signal by nearly coinciding the start and end position of the first and second detection gate signals and the first and second integrated gate signal respectively to the center of the pulse width of the first and second tracking error detection burst pulse signals. CONSTITUTION:The first and second tracking error detection burst pulse signals are supplied to a full-wave rectification detection circuit 6, thereby the first and second detection gate signal DG is obtained from a servo system processing circuit 10. The detection output is supplied to an integrator 7, thereby the first and second integrated gate signal IG is obtained from a servo processing circuit 10. The first and second tracking error detection burst pulse signals are recorded on a magnetic disk 1 so that the start and end positions of first and second detection gate signals and that of the first and second integrated gate signals are to be nearly coincided to the center of the pulse width of the first and second tracking error detection burst pulse signals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of recording a tracking error detection signal on a magnetic disk and a tracking error detection device.

[0002]

2. Description of the Related Art For example, sector servo signals are recorded in a plurality of radial directions of a hard disk (fixed disk),
Each sector servo signal includes a servo marker signal for each track, an address (track number, sector number) signal, and a two-phase tracking error detecting burst pulse signal.

Therefore, in the reproducing circuit of the hard disk,
The reproduction signal of the two-phase tracking error detection burst pulse signal reproduced by the magnetic head is subjected to full-wave rectification detection and then integrated, and the integrated signals are compared in level to obtain a tracking error signal. In that case, a detection gate signal and an integration gate signal are generated with reference to the reproduction signal of the servo marker signal, and used for detection and integration.

[0004]

However, since the two-phase tracking error detection burst pulse signal is recorded independently of the marker signal, the two-phase tracking error detection burst pulse signal detection gate for the reproduction signal is detected. If the phases of the signal and the gate signal for integration are not appropriate, there is a possibility that a highly accurate tracking error signal cannot be obtained.

In view of such a point, the present invention is to propose a tracking error detecting signal recording method and a tracking error detecting device which can obtain a highly accurate tracking error signal.

[0006]

According to a first aspect of the present invention, a signal reproduced by a magnetic head is supplied from a magnetic disk 1 and a reproduced signal of a marker signal recorded on a recording track of the magnetic disk 1. And a signal reproduced by the magnetic head from the magnetic disk 1 is supplied to the marker signal detection circuit 9 for detecting the same, and the same frequency recorded at different positions on both sides of the track center of the recording track after the marker signal. Of the reproduction signal of the first and second burst pulse signals for tracking error detection, which are formed based on the detection output of the marker signal detection circuit 9.
Detection circuit 6 gated by the second and second detection gate signals and subjected to full-wave rectification detection, and the first and second detection outputs from the detection circuit 6 are supplied to detect the marker signal detection circuit. An integrator 7 which is gated and integrated by the first and second integration gate signals formed based on the output, and the first and second integration outputs from the integrator 7 are supplied to the level A level comparator 1 that is compared and outputs a tracking error signal
A method of recording a tracking error detection signal detected by a tracking error detection device having 0 and 0.

The starting positions of the first and second detection gate signals and the first and second integration gate signals are
Each of the first and second tracking error detection burst pulse signals coincides substantially with the center of the pulse width thereof, and the end positions of the first and second integration gate signals correspond to the first and second tracking error detection The first and second burst pulse signals for tracking error detection are recorded on the magnetic disk 1 so as to coincide with the approximate center of the pulse width of the burst pulse signal.

A second aspect of the present invention is the above tracking error detecting device, wherein the starting positions of the first and second detection gate signals and the first and second integration gate signals are respectively first and second. It coincides with the approximate center of the pulse width of the second burst pulse signal for tracking error detection, and
The first and second detection gate signals and the first detection gate signal and the second detection gate signal so that the end positions of the second and second integration gate signals coincide with the centers of the pulse widths of the first and second tracking error detection burst pulse signals. The first and second integration gate signals are set.

[0009]

Embodiments of the present invention applied to a recording method and a reproducing circuit for a hard disk (fixed disk) will be described in detail below with reference to the drawings. It can also be applied to floppy disks. First, the reproducing circuit will be described with reference to FIGS. FIG. 1 shows a timing chart,
FIG. 2 shows a reproducing circuit. The magnetic head H for writing / reading (recording / reproducing) records the signal from the writing / reading (recording / reproducing) amplifier 2 on the magnetic disk (hard disk) 1 and reads (reproduces) the recorded signal. , To the amplifier 2.

On the magnetic disk 1, sector servo signals are recorded in a plurality of radial directions. This sector servo signal is a servo marker signal for each track, followed by an address signal (track number and sector number signal),
The first and second burst pulse signals for tracking error detection are recorded as fine pattern signals at different positions on both sides of the following track center, that is, at positions that are not simultaneously reproduced by the magnetic head H.

The signal reproduced from the magnetic disk 1 by the magnetic head H is supplied to the peak detector 3 for waveform shaping through the amplifier 2. The peak detector 3 has an amplifier 4 in its first stage, and the output of the amplifier 4 is supplied to the peak detector 3 through a low-pass filter 5 for cutting high frequencies.

The reproduction output (reproduction pulse) from the peak detector 3 is supplied to the servo marker detection circuit 9,
The servo marker signal {FIG. 1 (C)} is detected. The output of the low-pass filter 5, that is, the first and second tracking error detecting burst pulse signals {FIG. 1 (A),
(B)} differential output {FIG. 3 (A)} is supplied to the full-wave rectification detection circuit 6, and the first and second detections from the servo system processing circuit (comprising a CPU or a random logic circuit) 10 are performed. Gate signal DG (FIGS. 1D, 1F and 3)
(B)} and full-wave rectification detection are performed to obtain first and second detection outputs {FIG. 3 (D)}.
The first and second detection outputs are supplied to the integrator 7,
The first and second integration gate signals IG {FIG. 1 (E), (G) and FIG. 3 (C)} from the servo processing circuit 10 are gated and integrated to obtain the first and second integration signals. An integrated output {FIG. 3 (E)} is obtained. The integrator 7 is reset by the reset signal RS from the servo system processing circuit 10 after the completion of the first and second integration gate signals IG.

The first and second integrated outputs are respectively A / D
After being supplied to the converter 8 and converted into a digital signal, it is supplied to the servo system processing circuit 10 and stored in the memory thereof, and at the same time, the levels are compared therewith, and based on the obtained tracking error signal, the magnetic The head H is controlled to control tracking.

Then, as shown in FIG. 1, the first and second detection gate signals {FIG. 1 (D), (F)} and the first and second integration gate signals {FIG. 1 (E), Both the start position and the end position of (G)} are the first and second burst pulse signals for tracking error detection (for example, the cycle is 250 nsec, the duty is 50%, but each is limited to these). is not)
The first and second burst pulse signals for tracking error detection are recorded on the magnetic disk 1 so as to coincide with the approximate centers of the pulse widths in FIGS. 1A and 1B. In this case, the start positions of the first and second integration gate signals are the same as the start positions of the first and second detection gate signals, respectively, or the first and second tracking error detection bursts. The position is delayed by one or a plurality of cycles of the pulse signal. Further, the end positions of the first and second integration gate signals are the same as the start positions of the first and second detection gate signals, respectively, or the first and second tracking error detection burst pulses. It is a position delayed by one or more cycles of the signal.

Alternatively, as shown in FIG. 1, first and second detection gate signals {FIG. 1 (D), (F)} and first and second integration gate signals {FIG. 1 (E), Both the start position and the end position of (G)} are the first and second burst pulse signals for tracking error detection (for example, the cycle is 250 nsec, the duty is 50%, but each is limited to these). is not)
The first and second detection gate signals and the first and second integration gate signals are set so as to coincide with the center of the pulse width of {FIGS. 1A and 1B}. In this case as well, the start positions of the first and second integration gate signals are the same as the start positions of the first and second detection gate signals, respectively, or the first and second tracking error The position is delayed by one or a plurality of cycles of the burst pulse signal for detection. Further, the end positions of the first and second integration gate signals are the same as the start positions of the first and second detection gate signals, respectively, or the first and second tracking error detection burst pulses. It is a position delayed by one or more cycles of the signal.

Thus, as shown in FIGS. 3, 4 and 5, the first and second detection gate signals and the first and second detection gate signals with respect to the reproduction signals of the first and second tracking error detection burst pulse signals. Even if the relative start or end position of the integration gate signal of is slightly shifted, or the absolute value of the peak value of the positive and negative pulses of the reproduction signal of the first and second tracking error detection burst pulse signals is slightly different, Even if the frequencies of the reproduction signals of the first and second tracking error detection burst pulse signals change slightly, the start positions of the first and second detection gate signals and the first and second integration gate signals And the end position are at the center of the in-phase (same pattern) zero portion of the reproduction signal (differential signal) of the first and second tracking error detecting burst pulse signals, and the positive and negative pulse The number in claiming equal, the tracking error signal obtained from the difference between the first and second integrated output consists as to precision without receiving these influences.

[0017]

According to the present invention described above, it is possible to obtain a tracking error detection signal recording method and a tracking error detection device which can obtain a highly accurate tracking error signal.

[Brief description of drawings]

FIG. 1 is a timing chart of an embodiment of the present invention.

FIG. 2 is a block diagram showing an embodiment of the present invention.

FIG. 3 is a timing chart used to explain an embodiment.

FIG. 4 is a timing chart used to explain an embodiment.

FIG. 5 is a timing chart used to explain an embodiment.

[Explanation of symbols]

 1 magnetic disk 2 amplifier 3 peak detector 4 amplifier 5 low-pass filter 6 full-wave rectification detection circuit 7 integrator 8 A / D converter 9 servo marker detection circuit 10 servo system processing circuit

Claims (4)

[Claims] 1. A marker signal detecting circuit for supplying a signal reproduced by a magnetic head from a magnetic disk to detect a reproduced signal of a marker signal recorded on a recording track of the recording medium, and a magnetic signal from the magnetic disk. A signal reproduced by a head is supplied, and first and second tracking error detecting burst pulse signals of the same frequency recorded at different positions on both sides of the track center of the recording track after the marker signal. Of the reproduction signal is gated by the first and second detection gate signals formed based on the detection output of the marker signal detection circuit and is subjected to full-wave rectification detection, and a detection circuit of the detection circuit. The first and second detection outputs are supplied, and the first and second detection outputs are formed based on the detection output of the marker signal detection circuit. And a level comparator which is supplied with the first and second integration outputs from the integrator and is level-compared to output a tracking error signal. A method for recording a tracking error detection signal detected by a tracking error detection device having: wherein the start positions of the first and second detection gate signals and the first and second integration gate signals are , And the end positions of the first and second integration gate signals coincide with the centers of the pulse widths of the first and second tracking error detection burst pulse signals, respectively. The first and second tracking error detecting burst pulses are arranged so as to coincide with the approximate center of the pulse width of the tracking error detecting burst pulse signal. A recording method for recording a tracking error detection signal, characterized in that a recording signal is recorded on the magnetic disk. 2. A sector servo signal including the marker signal and the first and second tracking error detecting burst pulse signals is recorded in a plurality of radial directions on the magnetic disk. The method for recording the tracking error detection signal according to 1. 3. A marker signal detection circuit for supplying a signal reproduced by a magnetic head from a magnetic disk to detect a reproduced signal of a marker signal recorded on a recording track of the recording medium, and a magnetic signal from the magnetic disk. A signal reproduced by a head is supplied, and first and second tracking error detecting burst pulse signals of the same frequency recorded at different positions on both sides of the track center of the recording track after the marker signal. Of the reproduction signal is gated by the first and second detection gate signals formed based on the detection output of the marker signal detection circuit and is subjected to full-wave rectification detection, and a detection circuit of the detection circuit. The first and second detection outputs are supplied, and the first and second detection outputs are formed based on the detection output of the marker signal detection circuit. And a level comparator which is supplied with the first and second integration outputs from the integrator and is level-compared to output a tracking error signal. A tracking error detecting device having: a start position of the first and second detection gate signals and a starting position of the first and second integration gate signals, respectively. And make it coincide with the approximate center of the pulse width of the burst pulse signal for
The first and second integration gate signals are terminated so that their end positions coincide with the centers of the pulse widths of the first and second tracking error detection burst pulse signals.
And a second detection gate signal and the first and second integration gate signals are set. 4. A sector servo signal containing the marker signal and the first and second tracking error detecting burst pulse signals is recorded in a plurality of radial directions on the magnetic disk. The tracking error detection device according to claim 3.