ADAPTIVE DATA FORMAT METHOD INTEGRATING SPARE SECTORS
The performance capability of different heads that are part of the same hard disk drive (HDD) are utilized by an adaptive format that includes a plurality of storage zones and at least one reset zone that are distributed along a radius of the hard disk such that a reset zone is disposed between two adjacent storage zones. Each storage zone has a plurality of associated data tracks and each reset zone includes a plurality of data tracks. The number of data tracks associated with each respective storage zone is based on a performance capability of a head associated with the hard disk and includes at least one data track of at least one reset zone adjacent to the storage zone when the number of data tracks associated with the storage zone exceeds the number of data tracks that are between each reset zone adjacent to the storage zone.
Latest Hitachi Global Storage Technologies Netherlands BV Patents:
- Method of manufacturing a magnetic head
- Thin film magnetic head having an angled insulating film
- Magnetic head and manufacturing method thereof
- Magnetic shield, manufacturing method thereof and thin film magnetic head employing the same
- Perpendicular recording magnetic head with a main magnetic pole piece and an auxiliary magnetic pole piece
1. Field of the Invention
The present invention relates to hard disk drives (HDDs). More particularly, the present invention relates to an adaptive format that takes advantage of the performance capability of different heads that are part of the same HDD.
2. Description of the Related Art
Adaptive format techniques are well known for modifying the structure of customer data on each magnetic disk 102 of HDD 100 to compensate for the radial position on each disk and for the bits-per-inch (BPI) performance capability of each head. Nevertheless, the complexity of implementation of conventional adaptive formats has caused only a small percentage of HDDs in the marketplace use an adaptive format technique.
Although storage zones 301-303 are each depicted as being about the same size in
One conventional approach to take advantage of the variations in BPI performance capability of different heads is to use a variable-zone-by-head adaptive format technique on a TPI by head or by BPI by head basis.
A conventional variable-zone-by-head adaptive format can be characterized by zones that vary by the BPI performance capability of the corresponding head. For example, as shown in
Continued market pressures to increase areal densities of HDDs and the slowing of the read/write technology to achieve continued increased areal densities, new adaptive format techniques are needed.
Consequently, what is needed is an adaptive format technique that takes advantage of the performance capability of different heads that are part of the same HDD and that is not utilized by a conventional standard format technique. What is also needed is an adaptive format that does not have the disadvantage of creep exhibited by a conventional variable-zone-by-head adaptive format.
BRIEF SUMMARY OF THE INVENTIONThe present invention provides a simplified adaptive format technique that takes advantage of the capability performance of different heads that are part of the same HDD and that is not utilized by a conventional standard format technique. Additionally, the adaptive format of the present invention does not suffer from the disadvantage of creep exhibited by a conventional variable-zone-by-head adaptive format.
The advantages of the present invention are provided by an adaptive format for a hard disk of a hard disk drive that includes a plurality of storage zones and at least one reset zone. The storage zones and each reset zone are distributed along a radius of the hard disk with a reset zone being disposed between two adjacent storage zones. Each storage zone has a plurality of associated data tracks and each reset zone includes a plurality of data tracks. The number of data tracks associated with each respective storage zone is based on a performance capability of a head associated with the hard disk. The number of tracks associated with each respective reset zone is based on predetermined allowed track creep and performance requirements for the hard disk drive. According to the invention, the performance capability of the head can be a tracks-per-inch performance capability and/or a bits-per-inch performance capability of the head.
The present invention also provides a hard disk drive having at least one head, and a hard disk associated with each head. The hard disk has a plurality of storage zones and at least one reset zone. The storage zones and each reset zone are distributed along a radius of a hard disk with a reset zone being disposed between two adjacent storage zones. Each storage zone has a plurality of associated data tracks and each reset zone includes a plurality of data tracks. The number of data tracks associated with each respective storage zone is based on a performance capability of a head associated with the hard disk and includes at least one data track of at least one reset zone that is adjacent to the storage zone when the number of data tracks associated with the storage zone exceeds a number of data tracks that are between each reset zone. A plurality of adjacent storage zones can have the same tracks-per-inch storage capability and/or the same bits-per-inch storage capability. According to the invention, the performance capability of the head can be a tracks-per-inch performance capability and/or a bits-per-inch performance capability of the head.
BRIEF DESCRIPTION OF THE DRAWINGSThe present invention is illustrated by way of example and not by limitation in the accompanying figures in which like reference numerals indicate similar elements and in which:
The present invention provides a simplified adaptive format technique that takes advantage of the performance capability of different heads that are part of the same HDD and that is not utilized by a conventional standard format technique. Moreover, the adaptive format of the present invention does not suffer from the disadvantage of creep exhibited by a conventional variable-zone-by-head adaptive format. In this regard, the adaptive format of the present invention allows for either the bits-per-inch or the tracks-per-inch or both at a given point along the radius of a hard disk to be different for different heads on the same HDD. Additionally, the adaptive format of the present invention allows unused blocks to be assigned, thereby further increasing the overall performance of an HDD.
The reset-on-the-zone adaptive format of the present invention allows the BPI and/or the TPI to be different for each head for a given position along the radius of a hard disk. For example, as shown in
The present invention also includes reset zones 706 that are positioned at regular intervals across the radius of a disk and that span a short distance, typically four to five tracks wide. The distance a storage zone for a particular head extends into a particular reset zone can differ from head to head. For example, zone 701 for head n+1 extends into reset zone 706a toward the ID of the disk to the greatest number of tracks. Similarly, zone 702 for each of heads n, n+2 and n+3 extend into reset zone 706b toward the ID of the disk to a lesser number of tracks. Additionally, a region of a hard disk designated to have a predetermined BPI storage density and/or data rate can have a plurality of storage zones and a plurality of reset zones
Depending upon the number of defects found during the manufacturing process, however, the difference in the number of tracks that a storage zone extends into a reset zone could change or even reverse, that is, extend into a reset zone toward the OD of the hard disk. Tracks 705 within a reset zone 706 can be used as buffer sectors for defective sites and/or for spares in the field, thereby minimizing the number of wasted storage space.
Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced that are within the scope of the appended claims. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.
Claims
1. An adaptive format for a hard disk of a hard disk drive, the adaptive format comprising a plurality of storage zones and a plurality of reset zones alternatingly distributed along the radius of a hard disk, each reset zone being separated by a first predetermined number of data tracks and containing a second predetermined number of data tracks, and each storage zone including a number of data tracks that is based on a performance capability of a head associated with the hard disk and overlapping at least one reset zone that is adjacent to the storage zone when the number of data tracks of the storage zone exceeds the first number of data tracks separating consecutive reset zones.
2. The adaptive format according to claim 1, wherein the performance capability of the head is a tracks-per-inch performance capability of the head.
3. The adaptive format according to claim 1, wherein the performance capability of the head is a bit-per-inch performance capability of the head.
4. The adaptive format according to claim 3, wherein the performance capability of the head is further based on a tracks-per-inch performance capability of the head.
5. The adaptive format according to claim 1, wherein a plurality of adjacent storage zones have the same bits-per-inch storage capability.
6. The adaptive format according to claim 1, wherein a plurality of adjacent storage zones have the same tracks-per-inch storage capability.
7. The adaptive format according to claim 6, wherein a plurality of adjacent storage zones further have the same bits-per-inch storage capability.
8. The adaptive format according to claim 1, wherein a number of tracks associated with each respective reset zone is based on predetermined allowed track creep for the hard disk drive.
9. The adaptive format according to claim 8, wherein the number of tracks associated with each respective reset zone is further based on a performance requirement for the hard disk drive.
10. A hard disk drive, comprising:
- at least one head; and
- a hard disk associated with each head, the hard disk having a plurality of storage zones and a plurality of reset zones alternatingly distributed along the radius of a hard disk, each reset zone being separated by a first predetermined number of data tracks and containing a second predetermined number of data tracks, and each storage zone including a number of data tracks that is based on a performance capability of a head associated with the hard disk and overlapping at least one reset zone that is adjacent to the storage zone when the number of data tracks of the storage zone exceeds the first number of data tracks separating consecutive reset zones.
11. The hard disk drive according to claim 10, wherein the performance capability of at least one head is a tracks-per-inch performance capability of the head.
12. The hard disk according to claim 10, wherein the performance capability of at least one head is a bit-per-inch performance capability of the head.
13. The hard disk drive according to claim 12, wherein the performance capability of at least one head is further based on a tracks-per-inch performance capability of the head.
14. The hard disk drive according to claim 10, wherein a plurality of adjacent storage zones have the same bits-per-inch storage capability.
15. The hard disk drive according to claim 10, wherein a plurality of adjacent storage zones have the same tracks-per-inch storage capability.
16. The hard disk drive according to claim 15, wherein a plurality of adjacent storage zones further have the same bits-per-inch storage capability.
17. The hard disk drive according to claim 10, wherein a number of tracks associated with each respective reset zone is based on predetermined allowed track creep for the hard disk drive.
18. The hard disk drive according to claim 17, wherein the number of tracks associated with each respective reset zone is further based on a performance requirement for the hard disk drive.
Type: Application
Filed: Feb 10, 2004
Publication Date: Aug 11, 2005
Applicant: Hitachi Global Storage Technologies Netherlands BV (AE Amsterdam)
Inventors: George Dunn (San Jose, CA), Daniel Malone (San Jose, CA)
Application Number: 10/775,269