Maxtor Corporation

Western Digital Technologies, Inc.

Hgst Netherlands, B.v.

Kazuhiro Saito

Erhard Theodor Schreck

Scott A Hughes

Donald Joseph Brunnett

Brian D Strom

Bruce C Schardt

Andrew LeFebvre

Michael L Mallary

Thao Anh Nguyen

Duc H Banh

Francis P Crimi

Jingbo Yu

Chris Hawks

Richard Oswald

Anthony R Hurtado

Tim Glassburn

Joerg Ferber

Duc Bahn

Bruce Alexander Wilson

Bruno Jean Marchon

Bernhard E Knigge

Weldon Mark Hanson

Qinghua Zeng

Roger William Wood

Xiaoping Hu

Soo-Choon Kang

Noureddine Kermiche

Mark Heimbaugh

Douglas J Krajnovich

Hongchao Tim Zhao

Hyunchul Shim

Jianfeng Xu

Various illustrative aspects are directed to a data storage device comprising a disk; a read/write head having read and write portions configured to read data from and write data to the disk; read and write heaters configured to thermally adjust read and write spacings of the read and write portions from the disk surface; and a controller configured to control power applied to the read and write heaters based on a dual heater power ratio (DHR) of the respective power applied to each heater. The DHR is set based on a point during touchdown at which a reader shield and a writer shield have maximum contact with the surface of the disk (DHRmax).

Adaptive dual heater mode for hard disk drive

Techniques for determining a relative spacing between a read head and a surface of a magnetic data storage device may use at least two magnetic spacing measurement patterns. A first magnetic spacing measurement pattern may be offset from a center of a data track by a first offset value and a second magnetic spacing measurement pattern may be offset by a second, different, offset value. A processor may determine a first harmonic tone and a second harmonic tone from each of the first and second magnetic spacing measurement patterns. The processor also may determine respective ratios between amplitudes of the first and second harmonic tones for each of the first and second magnetic spacing measurement patterns. The processor may determine which ratio is greater, and may utilize the greater ratio when determining relative spacing between the read head and the surface of the magnetic data storage device.

Spacing measurement improvement in the presence of track mis-registration

Methods and systems for measuring variations in head-disk clearance in a hard disk drive. User generated data is randomly selected at a controller of the hard disk drive wherein the user generated data is stored on a disk associated with the hard disk drive. A reference point associated with the user generated data is stored on a storage medium associated with the hard disk drive. The user generated data is read at the controller. The user generated data is analyzed with the reference point using more than two frequencies, at the controller, to obtain a variation in measurement of the head-disk clearance.

Measuring variations in head-disk clearance in a hard disk drive

A disk drive to reduce head instability during disk drive manufacturing is disclosed. The disk drive comprises: a disk; a dynamic flying height (DFH) read/write head; a flying height actuator to control the spacing between the DFH read/write head and the disk; and a controller. The controller controls operations in the disk drive including applying a sloped increasing power between a first voltage and a second voltage to move the DFH read/write head towards the disk.

Disk drive to reduce head instability

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 method for monitoring the operability of a slider of a disk drive includes the steps of providing a slider that includes a read/write head that magnetically interacts with a storage disk, and a slider mover that adjusts a head-to-disk spacing, controlling an electrical stimulus to the slider mover with a drive circuitry, measuring an actual electrical response from the slider mover with the drive circuitry, and comparing the actual electrical response to an expected electrical response to determine an operability status of the slider mover. Further, changes in the actual electrical response can be monitored and used to predict future failure of the slider mover.

Method of detecting changes in operability status of a slider mover in a disk drive

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 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 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

Growing community of inventors

San Jose, CA, United States of America

Kazuhiro Saito