System and method for writing HDD depending on direction of head skew

• US 6,967,810 B2
• Filed: 09/29/2003
• Issued: 11/22/2005
• Est. Priority Date: 09/29/2003
• Status: Expired due to Term

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Hitachi Global Storage Technologies Netherlands BV (Western Digital Corporation)
• Inventors: Williams, Mason Lamar, Kasiraj, Prakash
• Primary Examiner(s): Hudspeth, David
• Assistant Examiner(s): OLSON, JASON C
• Application Number:
  US10/674,155
• Publication Number:
  US 20050068664A1
• Time in Patent Office: 785 Days
• Field of Search: 360/55, 360/75, 360/76, 360/78.01, 360/78.04, 360/78.08, 360/39, 360/40, 360/48, 360/61, 360/69
• US Class Current: 360/78.04
• CPC Class Codes: G11B 5/1278 specially adapted for magnetisations perpendicular to the surface of the record carrier
• CPC Class Codes: G11B 5/5526 Control therefor; circuits, track configurations or relative disposition of servo-information transducers and servo-information tracks for control thereof G11B5/556 takes precedence

Abstract

Data is written to a hard disk drive using shingled writing principles, i.e., each data track is partially overwritten when an immediately contiguous data track is written. Two or more contiguous data tracks establish a band, and a band may store data from an AV file. Tracks may be written in sequence toward or away from the inside diameter (ID) of the disk, depending on their radial location on the disk and the skew of the write element.

Claims

1. A hard disk drive (HDD) comprising:

at least one rotatable disk;

at least one write element configured for writing data to the disk in tracks; and

at least one HDD controller controlling the write element, the controller always writing adjacent tracks in sequence coward an inner diameter (ID) in a first radial region of the disk, the controller always writing adjacent tracks in sequence toward an outer diameter (OD) in a second radial region of the disk, wherein the first region is radially outward from the second region if the HDD employs perpendicular recording, and otherwise, if the HDD employs longitudinal recording, the first region is radially inward from the second region.

2. The HDD of claim 1, wherein at least one data band is established by at least two contiguous tracks.

3. The HDD of claim 1, wherein tracks in at least one of:

the first radial region, and the second radial region, define a truck pitch, and the write element defines a width equal to or larger than the track pitch.

4. The HDD of claim 1, wherein the write element is configured for perpendicular recording.

5. The HDD of claim 1, wherein the tracks are shingled.

6. The HDD of claim 1, further comprising a random update zone interposed between the first and second regions.

7. The HDD of claim 6, wherein a track pitch in the random update zone is equal to or larger than a track pitch in at least one of the first region, and the second region, to reduce adjacent track interference in the random update zone.

8. A magnetic disk data recording system comprising:

at least one disk defining an inner zone of at least one band of data, each band being established by at least two contiguous data tracks, the disk also defining an outer zone of at least one band of data and a mid-zone of at least one band of data between the inner and outer zones; and

control means for writing adjacent tracks in the inner zone always in a first radial sequence, track to track and for writing adjacent tracks in the outer zone always in a second radial sequence opposite to the first radial sequence, track to track, the control means executing random access writes to the mid-zone.

9. The system of claim 8, wherein tracks at least one of:

the inner zone, and the outer zone, define a truck pitch, and the control means controls a write element defining a width larger than the track pitch.

10. The system of claim 8, wherein a track pitch in the mid-zone is at least as large as a track pitch in at least one of:

the inner zone, and the outer zone, to reduce adjacent track interference in the mid-zone.

11. The system of claim 8, wherein the write element is configured for perpendicular recording, and the first radial sequence is radially outward.

12. The system of claim 8, wherein the write element is configured for longitudinal recording, and the first radial sequence is radially inward.

13. The system of claim 8, wherein the tracks are shingled.

14. A hard disk drive (HDD) comprising:

at least one disk defining bands of data each established by at least two contiguous concentric data tracks, the disk having at least an inner annular zone and an outer annular zone;

at least one write element configured for writing data so the disk; and

means for controlling the write element such that it writes data in tracks in the zones to avoid overwriting previously written tracks within the same band, wherein if the HDD employs perpendicular recording, the means for controlling always writes adjacent tracks in the inner annular zone sequentially radially outwardly on the disk, track to track, and always writes adjacent tracks in the outer annular zone sequentially radially inwardly on the disk, track to track, and otherwise, if the HDD employs longitudinal recording, the means for controlling always writes adjacent tracks in the inner annular zone sequentially radially inwardly on the disk, track to track, and always writes adjacent tracks in the outer annular zone sequentially radially outwardly on the disk, track to track.

15. The HDD of claim 14, wherein the means for controlling is at least one drive controller, the controller undertaking the controlling step by using radial writing sequence.

16. The HDD of claim 14, comprising an annular mid-zone between the inner and outer annular zones.

17. The HDD of claim 16, wherein a track pitch in the annular mid-zone is equal to or larger than a track pitch in at least one of:

the inner annular zone, and the outer annular zone.

18. The HDD of claim 14, wherein the tracks are shingled.

19. The HDD of claim 14, wherein tracks at least one of:

the inner annular zone, and the outer annular zone, define a track pitch, and the write element defines a width larger than the track pitch.