Maxtor Corporation

Seagate Technology Incorporated

Bruce C Schardt

Erhard Theodor Schreck

Thao Anh Nguyen

Donald Joseph Brunnett

Andrew LeFebvre

Scott A Hughes

Brian D Strom

Francis P Crimi

Kazuhiro Saito

Chris Hawks

Michael L Mallary

Duc H Banh

Jingbo Yu

Gang Herbert Lin

Xiaokun L Chew

Steven B Marshall

Joerg Ferber

Anthony R Hurtado

Duc Bahn

Robert McKenzie

Jack Tsai

Michael M Lee

Andrew W Vogan

Don Brunnett

Xiaoping Hu

Richard Oswald

Bernhard Hiller

Maurice L Schlumberger

Hung V Nguyen

Davide Guarisco

Mark Heimbaugh

Chandra Shaker Buddhavaram

David Chew

Samuel Richard Duell

Pantelis Alexopoulos

Douglas J Krajnovich

Tim Glassburn

Bill Edward Higgins

Leroy L Leach

Rickmer Kose

Eric Kvamme

Robert L Kimball

Richard Sonnenfeld

Hyunchul Shim

Thierry Chatard

Jeff Griffiths

Johanna Hernandez

James McGrath

Kathleen Fitzgerald, Legal Representative

Robert Milby

A RAID system is provided which can be implemented as a hardware RAID system while avoiding certain shortcomings of previous RAID systems. The RAID system makes it possible to avoid or reduce the number of buffers or processors and can take advantage of drive logic to achieve RAID functions or enhancements. RAID functionality can be provided in a manner to accommodate one or more ATA drive interfaces. To avoid drive replacement problems, host requests for drive serial numbers are responded to with a mirror serial number. In one embodiment, the read address is used to select which drive will perform a read operation.

RAID system and method compatible with improved drive select

In one example, a method is provided and includes comparing a measured change in spacing between a transducer element and a storage element in response to a fly height control signal with an expected change in spacing for the applied fly height control signal. The method also includes detecting an event condition based on the comparison between the measured change in spacing and the expected change in spacing.

Actuation efficiency based contact detection

A method for manufacturing a first disk drive includes incorporating a first storage disk having a first storage surface, and a first slider having a first read/write head and a slider mover into the first disk drive. Further, the first read/write head is movably positioned a first head-to-disk spacing relative to the first storage surface. The method also includes determining an incremental power level necessary to be delivered to a second slider mover of a second slider having a second read/write head to adjust a second head-to-disk spacing relative to a second storage surface by a predetermined increment. In addition, the method includes adjusting a first head-to-disk spacing by directing an operational power level to the first slider mover. The operational power level is derived from the incremental power level. The step of determining an incremental power level can include directing power to the second slider mover and detecting approximately when a portion of the second slider first contacts the second storage surface. Moreover, the step of adjusting can be performed during one or more manufacturing operations of the first disk drive.

Method for adjusting head-to-disk spacing in a disk drive

A disk drive for storing data includes a drive housing, a storage disk that is rotatably coupled to the drive housing, a slider assembly positioned near the storage disk, and a drive circuitry. The slider assembly includes a head that interacts with the storage disk during a data transfer operation. The drive circuitry performs a performance test on the head at a first HtD spacing and at a second HtD spacing that is different than the first HtD spacing while the drive is operation. The slider assembly includes a slider mover that moves the head between the first HtD spacing and the second HtD spacing. The slider mover can move the head to the first HtD spacing during the data transfer operation if the result of the performance test is a first test result and the slider mover moves the head to the second HtD spacing during the data transfer operation if the result of the performance test is a second test result.

Disk drive with performance driven head-to-disk spacing

A disk drive includes a slider assembly and a controller that directs current to the slider assembly to dynamically adjust the head-to-disk spacing. In one embodiment, the slider assembly includes a write element having a first end, a second end and an intermediate section, a conductor that is connected to the intermediate section. In this embodiment, the controller directs electrical current through the conductor to heat the write element without writing data to a storage disk. The electrical current can be directed through the conductor at any time prior to data transfer or during data transfer. Heating the write element causes a deformation of the slider assembly to decrease the head-to-disk spacing. In another embodiment, the slider assembly includes a separate slider deformer. Electrical current is selectively directed to the slider deformer to cause a deformation of the slider assembly to obtain a desired head-to-disk spacing. The slider deformer can include electrically conductive material or can be a piezoelectric element. Further, the slider deformer can be serpentine-shaped or substantially planar in shape.

Dynamically adjustable head disk spacing slider using thermal expansion

A disk drive includes a rotatable storage disk, an actuator motor, a slider that magnetically interacts with the storage disk, and a drive circuitry. A portion of the slider moves between a first position wherein the slider does not contact the storage disk and a second position wherein the slider contacts the storage disk. The drive circuitry can detect when the position of the slider changes between these positions. In one embodiment, the drive circuitry monitors off-track movement of the slider to detect when the slider has moved between these positions. The drive circuitry can also current that is directed to the actuator motor that is used to compensate for off-track movement to detect when the slider moves between these positions. In yet another embodiment, the drive circuitry monitors a rotational velocity of the storage disk to detect approximately when the slider moves between these positions.

System for detecting a change in head-to-disk contact status in a disk drive

A disk drive includes a rotatable data storage disk, a transducer, an actuator, and a controller. The transducer is configured to read and write data on the disk. The actuator is configured to position the transducer relative to defined portions of the disk. The controller is configured to determine how many times data has been written to the defined portions of the disk. The controller is also configured to refresh data residing at a particular one of the defined portions of the disk when the number of times data has been written to the particular defined portion of the disk satisfies a threshold value.

Disk drive that refreshes data on portions of a disk based on a number of write operations thereto

A disk drive having a drive housing, a storage disk that is rotatably coupled to the drive housing, and a slider assembly that includes a head and a slider mover. The head reads data from the storage disk during a read operation and writes data to the storage disk during a write operation. The slider mover maintains the head at a read HtD spacing during the read operation, at a pre-write HtD spacing during the read operation prior to the write operation, at a write HtD spacing during the write operation, and at an idle HtD spacing when the drive is not performing the read operation or the write operation. The disk drive includes a drive circuitry that directs a read power level to the slider mover to maintain the head at the read HtD spacing, a pre-write power level to maintain the head at the pre-write HtD spacing, a write power level to maintain the head at the write HtD spacing, and a idle power level to maintains the head at the idle HtD spacing.

Disk drive that positions a head at multiple head-to-disk spacings

A disk drive includes a drive housing, a storage disk, a slider and a drive circuitry. The storage disk has an inner and an outer diameter. The slider includes a read/write head and a slider mover that receives power from the drive circuitry to position the read/write head at a predetermined head-to-disk spacing during radial movement of the slider relative to the storage disk. The drive circuitry can direct a varying level of power to the slider mover during radial movement of the slider. In addition, the drive circuitry can increase the power to the slider mover as the read/write head nears a target track in order to decrease the head-to-disk spacing at the appropriate time. The drive circuitry can adjust the power to the slider mover so that the head-to-disk spacing remains within a predetermined range as the slider moves radially relative to the storage disk. The drive circuitry can also direct power to the slider mover so that the head-to-disk spacing is substantially the same at the start of a seek operation and when the read/write head arrives at a target track. The drive circuitry can also direct power to the slider mover based at least partially on the temperature of a portion of the slider.

System and method for adjusting head-to-disk spacing in a disk drive

A disk drive includes a drive housing, a storage disk, a slider and a drive circuitry. The slider magnetically interacts with the storage disk, and includes a read/write head that is positioned to have an actual head-to-disk spacing greater than zero nanometers during rotation of the storage disk. The drive circuitry can determine and/or monitor the actual head-to-disk spacing at any time during the operation of the disk drive based on an amplitude or a change in the amplitude of a signal such as a variable gain amplifier signal. In one embodiment, the slider includes a slider mover that receives current via the drive circuitry and causes a deformation of a portion of the slider to change the head-to-disk spacing based on the amplitude of the signal. In another embodiment, the read/write head moves during substantially consistent rotational velocity of the storage disk from a first actual head-to-disk spacing equal to approximately zero nanometers, to a second actual head-to-disk spacing that is greater than zero nanometers based on a desired amplitude of the signal.

System for monitoring and dynamically adjusting head-to-disk spacing in a disk drive

A method and apparatus is provided for measuring a media thermal decay rate for a disk in a disk drive. In one embodiment, reference patterns are written in a plurality of reference sectors on a test track of a disk surface. A thermal decay measurement duration is predetermined. After at least two decades of time longer than the predetermined thermal decay measurement duration have passed since writing the reference patterns in the plurality of reference sectors, sector-under-test patterns are written in a plurality of sectors-under-test, wherein the sectors-under-test and the reference sectors are written in data sectors and alternate with one another about at least a portion of the test track. The mean square error is measured and averaged for the reference sectors, and the mean square error is measured and averaged for the sectors under test. The averaged mean square error for the reference sectors and the averaged mean square error for the sectors-under-test are used to calculate the media thermal decay rate. In another embodiment, information associated with the amplitude of the readback signal is used instead of, or in addition to, the mean square error of the readback signal to calculate the media thermal decay rate.

Method and apparatus for media thermal decay measurement in a disk drive

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Tracey, CA, United States of America

Bruce C Schardt