Western Digital Technologies, Inc.

Western Digital Corporation

Western Digital (sea), Pte., Ltd.

Raffi Codilian

David D Nguyen

Joseph M Viglione

Anil Sareen

William D Johns

Kamran Oveyssi

Thomas D Hanan

Ara W Nazarian

Lan V Ngo

Robert P Ryan

George J Bennett

Timothy A Ferris

Wally Szeremeta

Shawn E Casey

Dalwinder Singh

Serge Hauert

Steven J Alfred

Brian Kenneth Tanner

Jack M Chue

Gregory B Thelin

Lin Yang

Charles A Park

Timothy J Elliott

Charles W Frank, Jr

Aswartha Narayana

Kent William Gibbons

Steven Nemshick

Jorge Haro

Steven L Webb

Donald George Stupeck

Arafat M Butt

Donald R Turner

Roger G Davis

Jie Yu

Michael Stephen Rothberg

Hanan Kupferman

Charles Royston Patton, Iii

Hemant Melkote

Choo-Bhin Ong

Alexander Babinski

Vinay Kumar Agarwal

Jonathan Lee Hanmann

Mark F Vallis

Yoo H Kim

Carl R Messenger

Shuo-Hao Chen

Norman D Gardner

Shan-Shuong Chiou

Terry C Dawson

Travis E Ell

David L Whitaker

Ralph A Proud

George S Bouchaya

Iftikhar K Baqai

Kin-Cheok Pong

Jim G Saunders

David D T Nguyen

An-Chieh Chang

Yie Ju

Iftikhar A Baqai

Edgar De-Jia Sheh

A rotating media storage device (RMSD) that adaptively modifies pre-read operations is disclosed. The RMSD schedules a pre-read data segment on a second track of disk, commands a movable head to seek to the second track, and if an on-track condition is not met for the scheduled pre-read data segment, modifies the pre-read operation. In one example, modifying the pre-read operation includes canceling the pre-read operation and then performing a read data operation.

Adaptively modifying pre-read operations within a rotating media storage device

A disk drive is disclosed comprising a disk, and a head actuated over the disk. Control circuitry within the disk drive is operable to write a plurality of code segments to a primary area of the disk, and write the code segments to a backup area of the disk. The control circuitry reads the code segments from the primary area of the disk and executes the code segments read from the primary area of the disk. After reading the code segments from the primary area of the disk and executing the code segments, the control circuitry verifies recoverability of the code segments from the backup area of the disk, and when the verification fails, copies the code segments from the primary area of the disk to the backup area of the disk.

Disk drive maintaining multiple copies of code segments

A method of fabricating disk drives. The method includes providing disk drives based upon a first disk drive configuration. The first disk drive configuration includes an operable disk drive including a disk drive base with an exterior bottom side, and a first weight plate attached to the exterior bottom side of the disk drive base. The method further includes providing disk drives based upon a second disk drive configuration. The second disk drive configuration includes the operable disk drive, and a second weight plate attached to the exterior bottom side of the disk drive base. The second weight plate has a mass different than a mass of the first weight plate. In another embodiment, the second disk drive configuration includes the disk drive base being exposed without any weight plated attached. Another aspect of the invention includes a disk drive with a weight plate.

Method of fabricating disk drives using a common disk drive base with an attached weight plate, and a disk drive including the same

A spindle motor includes a shaft defining a longitudinal axis, a hub, a bearing assembly disposed between the hub and the shaft for allowing the hub to rotate, and a stator. The stator includes an inner diameter, an outer diameter, a stator tooth having a distal end, and a coil wound around the stator tooth. The stator tooth has a lower surface extending between the coil and the distal end of the stator tooth. The spindle motor includes a stator support structure supporting one of the inner and outer diameters, the stator support structure having an upper surface facing the lower surface, wherein at least one of the upper surface of the stator support structure and the lower surface of the stator tooth defines a cavity.

Disk drive spindle motor having a cavity defined by one of an upper surface of a stator support structure and a lower surface of a stator tooth

A printed circuit board on which multiple component-dedicated alignment line indicators including parallel lines may be used to facilitate the evaluation and segregation process during the production of printed circuit board assemblies based on the alignment characteristics of mounted disk drive electrical components with respect to these parallel lines. Each electrical component defines a perimeter with edges defining a first and second lateral distances and corners defining a diagonal distance. The alignment line indicators include first and second inner line segments spaced apart a first inner spacing at least the first lateral distance and less than the diagonal distance. The alignment line indicators include third and fourth inner line segments spaced apart at least the second lateral distance and less than the diagonal distance. The alignment line indicators include first and second outer line segments spaced apart more than the first inner spacing and less than the diagonal distance.

Disk drive printed circuit board with component-dedicated alignment line indicators including inner and outer line segments

A disk drive is disclosed comprising a disk having a plurality of data tracks, wherein each data track comprises a plurality of data sectors, and a head is actuated over the disk. A suspect sector list (SSL) stores a plurality of SSL entries, wherein each SSL entry identifies at least one suspect data sector. The disk drive further comprises a disk controller for executing an access command received from a host computer to access at least one of the data sectors. If an error is detected while executing the access command, the disk controller generates an SSL entry having a priority level selected from at least three priority levels and adds the SSL entry to the SSL. A verification operation is executed for each suspect data sector identified by each SSL entry, wherein the SSL entries are processed relative to the priority level assigned to each SSL entry.

Disk drive performing multi-level prioritization of entries in a suspect sector list to identify and relocate defective data sectors

The invention may be embodied in a method for operating a disk drive in a mobile device to optimize power usage based on an application category. The mobile device may be a hand held computing device such as a personal digital assistant (PDA) or a mobile terminal such as a cellular telephone. A technique of the invention may spin down the disk drive after an adjustable delay time interval that is set based on an application category associated with a most recent data transfer command.

Method for setting a power operating mode transition interval of a disk drive in a mobile device based on application category

The invention may be embodied in a disk drive for use in a mobile device. The mobile device may be a hand held computing device such as a personal digital assistant (PDA) or a mobile terminal such as a cellular telephone. The mobile device includes a host processor for accessing data on the disk drive. The disk drive has a rotating disk media and a moveable read/write head disposed over the disk media. The disk media is divided into a first data storage zone and a second data storage zone. The data storage zones are radially disposed in discrete areas of the disk media and each zone has a plurality of tracks for storing data. The mobile device may read data from the first data storage zone when the mobile device is in a mobile environment. The mobile device may read data from the second data storage zone only when the mobile device is in a non-mobile environment and may not read data from the second data storage zone when the mobile device is in a mobile environment.

Mobile device and disk drive restricted from reading a data storage zone in a mobile environment

A disk drive is disclosed for optimizing write current settings relative to drive operating characteristics and an ambient temperature reading. Test data is written to and read from the disk using different write current settings to generate a plurality of corresponding quality metrics. The quality metrics are evaluated to generate an optimized write current setting for the ambient temperature reading. In one embodiment, the first write current setting is selected relative to a previously optimized write current setting that corresponds to the ambient temperature reading. This embodiment expedites the optimization process by testing write current settings surrounding a previous write current setting rather than testing the entire range of write current settings.

Disk drive for optimizing write current settings relative to drive operating characteristics and ambient temperature readings

A rotating media storage device (RMSD) to adaptively estimate a read access time to a second track based on the radial position of the second track is disclosed. The RMSD includes a disk having at least a first track and a second track and a microprocessor for controlling operations in the RMSD including seek operations. During a seek operation, the microprocessor bins a radial position of the second track and estimates a read access time to the second track based on the binned radial position of the second track.

Adaptively estimating a read access time to a second track based upon the binned radial position of the second track within a rotating media storage device

An aspect of the invention can be regarded as a disk drive that includes a disk drive base and a spindle motor hub rotatably coupled to the disk drive base. The disk drive further includes a first disk disposed about the spindle motor hub and having a first disk stiffness. The disk drive further includes a second disk disposed about the spindle motor hub and having a second disk stiffness different than the first disk stiffness. According to another aspect of the present invention, the second disk has a second disk thickness different than a first disk thickness. According to another aspect of the present invention, the second disk is formed of a second material having a second material stiffness different than a first material stiffness.

Disk drive with disks having different disk stiffness, thickness and material combinations

A method for reducing a servo channel head gain calibration time comprising initiating a servo channel head gain calibration process for a head corresponding to the selected disk surface; obtaining a head gain calibration value for a pre-selected zone in the selected disk surface; comparing the obtained calibration value with a pre-stored calibration value for the pre-selected zone and generating a comparison result; and stopping the calibration process for the head if the comparison result does not exceed a threshold value.

Reducing head gain calibration time in a disk drive

The invention relates to a disk drive and related method for improved disk rotation rate control in the presence of seek operations. A spindle motor rotates a spindle, supporting at least one disk with a magnetic recording surface, in response to a motor current. The actuator radially positions a transducer head over the recording surface. The motor is subjected to a torque load component related to the transducer head radial position. The spindle motor controller has a feedback control loop and a feedforward control element. The feedback control loop maintains a relatively constant spindle rotation rate based on a difference error between a predetermined target spindle rotation rate parameter and a measured spindle rotation rate parameter. The feedforward control element, in conjunction with a seek operation, adjusts the motor current based on a target head radial position with respect to an initial head radial position.

Disk drive and method for improved disk rotation control

A method of manufacturing a disk drive and a disk drive where the width of the read element and the width of the write element are both measured at servo-writing time and the track pitch of the disk drive is set on the basis of those measurements. Disk drives with superior head width combinations are servo-written with a narrower track pitch in order to have a higher storage capacity. Disk drives with inferior head width combinations are detected before servo-writing so that the disk drive may be servo-written with wider track pitch rather than with a nominal track pitch that results in a subsequent drive failure during initial burn-in (IBI). The heads are used more efficiently in that heads that are more capable are used to their ability and less capable heads that would otherwise be disposed of are used at all.

Method of manufacturing and disk drive produced by measuring the read and write widths and varying the track pitch in the servo-writer

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Irvine, CA, United States of America

Raffi Codilian