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Hard disk drive, its manufacturing method, and servo data writing method

A hard disk drive, servo data technology, applied in data recording, instrumentation, alignment of tracks on the disk, etc., can solve the problems of discontinuous track spacing, address continuity, burst data repetition (continuity cannot be servo controlled, etc.)

Active Publication Date: 2019-07-05
KK TOSHIBA
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

That is, since the final track written last has a different width than the other tracks, there is a discontinuity in the track pitch
Therefore, in the vicinity of the final track, the continuity of the address and the repetition (continuity) of the burst data may be destroyed, making it impossible to perform servo control.

Method used

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  • Hard disk drive, its manufacturing method, and servo data writing method
  • Hard disk drive, its manufacturing method, and servo data writing method
  • Hard disk drive, its manufacturing method, and servo data writing method

Examples

Experimental program
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Effect test

no. 2 example

[0070] Since the block diagram of the second embodiment is the same as that of the first embodiment, illustration is omitted.

[0071] When the same address is overwritten in the reverse order write and ascending order write (the decimal point of step / 2 is rounded off), such as Figure 2C As shown in , the width of the address written in the final step of the ascending-order write that is not overwritten is very large compared with the width of other addresses. In order to eliminate this, in the first embodiment, in ascending order writing, a value obtained by rounding off the decimal point of (step-1) / 2 is written as an address. As a result, such as Figure 6A As shown, by shifting the position of the address one step inward, the width of the address written in the final step of ascending-order writing becomes the write head width MWW, which is substantially equal to the width of other addresses. However, the write head width MWW is 2.5 times the stride width, and the other...

no. 3 example

[0076] In the first and second embodiments, the switching step between reverse order writing and ascending order writing is set as a predetermined radial position (step), but the third embodiment is based on Figure 7 According to the principle shown, the switching step is automatically determined when writing in reverse order. Figure 7 The horizontal axis of is the radial position (the left side is the inner circumference, and the right side is the outer circumference), and the vertical axis is the gain of the servo AGC circuit included in the read / write channel 30 . The servo AGC circuit is a variable amplifier that amplifies the reproduced signal in order to keep the amplitude of the reproduced signal constant when reproducing the servo data. In the third embodiment, the servo data written with the write head is read out as read data. When the write head is located on the innermost circumference, servo data cannot be read because the read head is located on the outer peri...

no. 4 example

[0080] In the above-described embodiments, the servo data was written to the disk on which the spiral pattern was written by an external device, but the eccentricity of the disk was not assumed. However, in reality, a spiral pattern written by an external device may have an eccentric component and may not be a perfect circle. Due to the configuration of the spiral pattern, it is difficult to perform so-called imaginary circle control that removes eccentricity while following the spiral pattern. If there is eccentricity, a plurality of tracks are included in the switching area between reverse-order writing and ascending-order writing when the driver performs virtual circle control. When writing servo data bidirectionally, since the track pitch varies to some extent in the switching area between reverse-order writing and ascending-order writing, data cannot be written in such a switching area where servo data is written. However, in the case where the virtual circle control is ...

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Abstract

The embodiment of the present invention provides a hard disk driver, its manufacturing method, and servo data writing method.The serviced data writing method includes: the head of the peripheral or inner diameter of the inner direction of the disk, and the movement direction is reversed and the head is moved from the inside or peripheral to the middle diameter.Location, write a part of the servo data written in the last time with this servo data, write the servo data to the disk, the servo data has: address data, as the first phase of the phase, the first and second phase emergencies.The first emergencies of a certain one, as the first phase of the first phase and the second emergencies in the second phase of the second phase; the two continuous two radius positions in multiple radius positions are writtenThe servo data with an address with the same value; finally write the radius position of the servo data after the movement direction is reversed.Essence

Description

technical field [0001] Embodiments disclosed herein generally relate to hard disk drives (HDDs), methods of manufacturing the same, and servo data writing methods. Background technique [0002] In a hard disk drive, servo data is used to position a magnetic head (hereinafter, also only referred to as head) to a target track on a magnetic disk (hereinafter, also simply referred to as disk). A plurality of radial servo areas are provided on the disc, and the servo areas include a plurality of servo tracks, and servo data is written into the servo tracks. Servo data includes address, burst data. [0003] Servo data is recorded on a disk medium through a servo writing process included in the disk drive manufacturing process. An example of the servo writing process includes a self-servo writing method in which a disc on which a base pattern is recorded in advance is incorporated into a hard disk drive, and servo data is recorded on the disc by a write head based on the base pat...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G11B5/596
CPCG11B5/596G11B5/59633G11B5/59655
Inventor 秋谷慎介高石和彦佐渡秀夫
Owner KK TOSHIBA