Data storage device erasing multiple adjacent data tracks to recover from inter-track interference

• US 9,117,463 B1
• Filed: 06/23/2014
• Issued: 08/25/2015
• Est. Priority Date: 06/23/2014
• Status: Expired due to Fees

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Inventors: Tang, Kathy X., Le, Jerry G.
• Primary Examiner(s): Alunkal, Thomas
• Application Number:
  US14/312,514
• Time in Patent Office: 428 Days
• Field of Search: 360/55, 360/57, 360/45, 360/39, 360/66
• US Class Current: 1/1
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 2020/1869 Preventing ageing phenomena from causing data loss, e.g. by monitoring the age of record carriers or by recognising wear, and by copying information elsewhere when a record carrier becomes unreliable
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence
• CPC Class Codes: G11B 5/02 Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
• CPC Class Codes: G11B 5/024 Erasing

Abstract

A data storage device is disclosed comprising a disk comprising a plurality of data tracks, and a head actuated over the disk. A retry operation for a target data track is performed by positioning the head at a first radial location and first erasing at least part of a first data track adjacent the target data track. After the first erasing, the target data track is first read to first recover target data recorded in the target data track. When the first recovery fails, the head is positioned at a second radial location and more of the first data track is second erased. After the second erasing, the target data track is second read to second recover the target data recorded in the target data track.

Claims

1. A data storage device comprising:

a disk comprising a plurality of data tracks;

a head actuated over the disk; and

control circuitry configured to perform a retry operation for a target data track by;

positioning the head at a first radial location and first erasing at least part of a first data track adjacent the target data track;

after the first erasing, first reading the target data track to first recover target data recorded in the target data track;

when the first recovery fails, positioning the head at a second radial location and second erasing more of the first data track; and

after the second erasing, second reading the target data track to second recover the target data recorded in the target data track,

wherein;

the first erasing erases at least part of a second data track adjacent the first data track; and

the first erasing erases more of the second data track than the first data track.

2. The data storage device as recited in claim 1, wherein the second radial location is closer to the target data track than the first radial location.

3. The data storage device as recited in claim 1, wherein:

prior to the first erasing, the control circuitry is further configured to read first data from the first data track and read second data from the second data track; and

after the second erasing, the control circuitry is further configured to write the first data to the first data track and write the second data to the second data track.

4. The data storage device as recited in claim 1, wherein the first reading comprises positioning the head at a plurality of radial locations relative to the target data track and reading the target data track at each radial location.

5. The data storage device as recited in claim 1, wherein:

the target data comprises a first frequency range; and

the first erasing comprises writing an erase pattern to the first data track, where the erase pattern comprises magnetic transitions having a second frequency range different than the first frequency range.

6. The data storage device as recited in claim 5, wherein the erase pattern comprises an AC pattern comprising a frequency higher than the first frequency range.

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

performing a retry operation for a target data track of a disk by;

positioning a head at a first radial location and first erasing at least part of a first data track adjacent the target data track;

after the first erasing, first reading the target data track to first recover target data recorded in the target data track;

when the first recovery fails, positioning the head at a second radial location and second erasing more of the first data track; and

after the second erasing, second reading the target data track to second recover the target data recorded in the target data track,

wherein;

the first erasing erases at least part of a second data track adjacent the first data track; and

the first erasing erases more of the second data track than the first data track.

8. The method as recited in claim 7, wherein the second radial location is closer to the target data track than the first radial location.

9. The method as recited in claim 7, wherein:

prior to the first erasing, further comprising reading first data from the first data track and read second data from the second data track; and

after the second erasing, further comprising writing the first data to the first data track and writing the second data to the second data track.

10. The method as recited in claim 7, wherein the first reading comprises positioning the head at a plurality of radial locations relative to the target data track and reading the target data track at each radial location.

11. The method as recited in claim 7, wherein:

the target data comprises a first frequency range; and

the first erasing comprises writing an erase pattern to the first data track, where the erase pattern comprises magnetic transitions having a second frequency range different than the first frequency range.

12. The method as recited in claim 11, wherein the erase pattern comprises an AC pattern comprising a frequency higher than the first frequency range.