IP Library Granted Patent US 9,117,463
Granted Patent B1
US 9,117,463 · App. 14/312,514 · Granted Aug 25, 2015

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

Inventors: Kathy X. Tang (San Jose, CA); Jerry G. Le (Milpitas, CA)
Assignee: Western Digital Technologies, Inc.
G11B5/024G11B5/02
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Quick Facts
Patent No.
US 9,117,463
App. No.
14/312,514
Granted
Aug 25, 2015
Kind
B1
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 (38)

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.

Assignments (6)
RELEASE OF SECURITY INTEREST AT REEL 038744 FRAME 0481 Recorded Feb 8, 2022
From: JPMORGAN CHASE BANK, N.A.
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 058982/0556 →
RELEASE OF SECURITY INTEREST Recorded Mar 5, 2018
From: U.S. BANK NATIONAL ASSOCIATION, AS COLLATERAL AGENT
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 045501/0714 →
SECURITY AGREEMENT Recorded May 17, 2016
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 038722/0229 →
SECURITY AGREEMENT Recorded May 17, 2016
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: U.S. BANK NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 038744/0281 →
SECURITY AGREEMENT Recorded May 17, 2016
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 038744/0481 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 12, 2014
From: TANG, KATHY X.; LE, JERRY G.
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 033520/0402 →