Data storage device writing tracks on a disk with equal spacing

• US 8,953,277 B1
• Filed: 06/16/2014
• Issued: 02/10/2015
• Est. Priority Date: 06/16/2014
• Status: Active Grant

• Current Assignee: JP Morgan Chase Bank, N.A. (JP Morgan Chase & Co)
• Original Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Inventors: Wu, Xiao Z., Terrill, David D., Zhang, Huaan
• Primary Examiner(s): HINDI, NABIL Z
• Application Number:
  US14/305,753
• Time in Patent Office: 239 Days
• Field of Search: 360/75, 360/50, 360/48, 360/31, 360/73.12, 360/77.01, 360/78.14, 360/78.1, 360/77.08
• US Class Current: 360/75
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 2020/1281 Servo information
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence

Abstract

A data storage device is disclosed comprising a head actuated over a disk. A plurality of data tracks on the disk are first written, and a metric representing a spacing between at least two of the first written data tracks is generated. At least two of the plurality of data tracks are rewritten based on the generated metric such that the rewritten data tracks comprise a more equal spacing compared to the first written data tracks.

Claims

1. A data storage device comprising:

a disk;

a head; and

control circuitry configured to;

first write a plurality of data tracks on the disk;

first generate a metric representing a spacing between at least two of the first written data tracks; and

first rewrite at least two of the plurality of data tracks based on the first generated metric such that the first rewritten data tracks comprise a more equal spacing compared to the first written data tracks.

2. The data storage device as recited in claim 1, wherein the control circuitry is further configured to read servo data of servo tracks on the disk in order to servo the head over the disk when first writing the first plurality of data tracks on the disk.

3. The data storage device as recited in claim 2, wherein first rewriting the plurality of tracks on the disk based on the first generated metric compensates for a non-uniform spacing of the servo tracks.

4. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:

first write at least three data tracks on the disk; and

first generate the metric relative to an average spacing of the first written data tracks.

5. The data storage device as recited in claim 4, wherein a spacing between the first rewritten data tracks is proximate the average spacing of the first written data tracks.

6. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:

second generate the metric representing a spacing between at least two of the first rewritten data tracks; and

second rewrite at least two of the plurality of data tracks based on the second generated metric such that the second rewritten data tracks comprise a more equal spacing compared to the first rewritten data tracks.

7. The data storage device as recited in claim 1, wherein the control circuitry is further configured to:

generate a track spacing profile representing a spacing between adjacent data tracks relative to the metric; and

first generate the metric representing the spacing between the at least two of the first written data tracks by reading the at least two of the first written data tracks.

8. The data storage device as recited in claim 7, wherein the metric comprises a track average amplitude (TAA).

9. The data storage device as recited in claim 1, wherein the control circuitry is further configured to first write the plurality of data tracks on the disk in a shingled manner.

10. A method of operating a data storage device, the method comprising:

first writing a plurality of data tracks on a disk;

first generating a metric representing a spacing between at least two of the first written data tracks; and

first rewriting at least two of the plurality of data tracks based on the first generated metric such that the first rewritten data tracks comprise a more equal spacing compared to the first written data tracks.

11. The method as recited in claim 10, further comprising reading servo data of servo tracks on the disk in order to servo a head over the disk when first writing the first plurality of data tracks on the disk.

12. The method as recited in claim 11, wherein first rewriting the plurality of tracks on the disk based on the first generated metric compensates for a non-uniform spacing of the servo tracks.

13. The method as recited in claim 10, further comprising:

first writing at least three data tracks on the disk; and

first generating the metric relative to an average spacing of the first written data tracks.

14. The method as recited in claim 13, wherein a spacing between the first rewritten data tracks is proximate the average spacing of the first written data tracks.

15. The method as recited in claim 10, further comprising:

second generating the metric representing a spacing between at least two of the first rewritten data tracks; and

second rewriting at least two of the plurality of data tracks based on the second generated metric such that the second rewritten data tracks comprise a more equal spacing compared to the first rewritten data tracks.

16. The method as recited in claim 10, further comprising:

generating a track spacing profile representing a spacing between adjacent data tracks relative to the metric; and

first generating the metric representing the spacing between the at least two of the first written data tracks by reading the at least two of the first written data tracks.

17. The method as recited in claim 16, wherein the metric comprises a track average amplitude (TAA).

18. The method as recited in claim 10, further comprising first writing the plurality of data tracks on the disk in a shingled manner.