Western Digital Technologies, Inc.

Censtor Corporation

Read Rite Corporation

International Business Machines Corporation

Other

Seagate Technology Incorporated

William C Cain

Darren Todd Imai

Dimitre A Latev

Harold J Hamilton

Robert D Hempstead

Michael E Devillier

David D Roberts

Alexander P Payne

William Bernard Boyle

Mei-Man L Syu

Kevin W McLaughlin

Robert Fontana

Barry Klein

Po-Kang Wang

Kroum Stanimirov Stoev

Keith R Berding

Yong Shen

Alan T Meyer

Hugo Alberto Santini

Hua-Ching Tong

Virgil V Wilkins

David Eugene Heim

Virgil S Speriosu

Eric J Champion

Durga P Ravipati

Randolph S Gluck

Davide Guarisco

Mason L Williams, Iii

Bernard Dieny

Michael A Baldwinson

Garrett A Garrettson

Shih-Cheng Cheng

Richard D Anderson

Matthew G Rutledge

Kwang K Kim

Chinying Sun

A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of tracks, each track comprising a plurality of data sectors. A circular buffer is defined comprising a plurality of the tracks. During a garbage collection operation, write data is read from previously written valid data sectors corresponding to a tail of the circular buffer and stored in a non-volatile cache. During a flush operation, the write data is flushed from the non-volatile cache to the disk.

Disk drive using non-volatile cache when garbage collecting log structured writes

A hybrid drive is disclosed comprising a head actuated over a disk comprising a plurality of data tracks, and a non-volatile semiconductor memory (NVSM) comprising a plurality of memory segments. When a life remaining of the NVSM falls below a threshold, the NVSM is marked as read only. When a write command is received from a host including write data, and when the NVSM is marked as read only, the write data is written to the disk and a corresponding memory segment in the NVSM is invalidated.

Hybrid drive converting non-volatile semiconductor memory to read only based on life remaining

A hybrid drive is disclosed comprising a head actuated over a disk, and a non-volatile semiconductor memory (NVSM). When a write command is received from a host that is mapped to the NVSM, the write command is serviced by writing data to the NVSM, and when a life remaining of the NVSM falls below a threshold, by also writing a copy of the data to the disk.

Hybrid drive writing copy of data to disk when non-volatile semiconductor memory nears end of life

A hybrid drive is disclosed comprising a head actuated over a disk comprising a plurality of data tracks, where each data track comprises a plurality of data sectors. The hybrid drive further comprises a non-volatile semiconductor memory (NVSM) comprising a plurality of memory segments. When a write command is received from a host including write data, the write data is written to one of a disk cache and a NVSM cache, wherein the write data is eventually flushed to a non-cache area of the disk.

Hybrid drive comprising write cache spanning non-volatile semiconductor memory and disk

A method of operating a peripheral data storage system(PDSS) for use with a host system configured to perform scheduled backup operations to PDSS comprising a user-actuated backup signaling subsystem(UBSS), a user-notifying device comprising first and second notifying states, and a host interface adapted for communication with the host system. The method comprises receiving a first signal from UBSS; communicating first signal to host system via host interface; receiving an acknowledgement signal from host system in response to communicating; and switching user-notifying device between first notifying state and second notifying state in response to received acknowledgement signal. Another method comprises receiving in host system a first request from PDSS for performing a task corresponding to a host-scheduled backup operation for a scheduled backing up of data to PDSS; completing the task by host system based on received first request; and notifying PDSS of completion of the task by host system.

Performing backup operations to peripheral data storage systems

A method of displaying states of a peripheral data storage system (PDSS) comprising a data storage device, a data storage system controller, a user-actuated signaling subsystem, a user display subsystem adapted to display the states, and a peripheral data storage controller host interface adapted for communication with a host system. The method includes determining a state of the PDSS; displaying a first display state via the user display subsystem if the PDSS is in an idle state; displaying a second display state via the user display subsystem if the PDSS is in a state corresponding to receiving a signal from the user-actuated signaling subsystem; displaying a third display state via the user display subsystem if the PDSS is in a dynamically active state; and displaying a fourth display state via the user display subsystem if the PDSS is in an off state.

Peripheral data storage system with multi-state user display

In an external disk drive system comprising a disk drive, a bridge controller comprising a plurality of Bridge Controller Host (BCH) interfaces adapted to establish communication between the external disk drive system and an external device via a plurality of different communication mediums, a method for switching from a first BCH-interface communicating with the external device via a first communication medium to a second BCH-interface during the operation of the external disk drive system. The method comprising sensing a connecting of a second communication medium to the external disk drive system via the second BCH-interface; determining an interface priority of the second communication medium over an interface priority of the first communication medium; dismounting the disk drive from the first communication medium based on the determining; and mounting the disk drive to the second communication medium wherein the external disk drive system remains operational during the dismounting an mounting.

Switching interfaces in external disk drives

An information storage system includes a transducer having a loop of ferromagnetic material with pole tips separated by an nonferromagnetic gap located adjacent to a medium such as a rigid disk. During writing the separation between the pole tips and the media layer of the disk is a small fraction of the gap separation. Due to the small separation between the pole tips and the media layer, the magnetic field generated by the transducer and felt by the media has a larger perpendicular than longitudinal component, favoring perpendicular recording over longitudinal recording. The media may have an easy axis of magnetization oriented substantially along the perpendicular direction, so that perpendicular data storage is energetically favored. The transducer may also include a magnetoresistive sensor for reading magnetic information from the disk.

Hard disk drive for perpendicular recording with transducer having submicron gap between pole tips

A hard disk drive head operates in close proximity and dynamic contact with a rapidly spinning rigid disk surface, the head including a transducer with a magnetically permeable path between a poletip disposed adjacent to the disk surface and a magnetoresistive (MR) sensor situated outside the range of thermal noise generated by the surface contact. The magnetically permeable path is the same as that used to write data to the disk, eliminating errors that occur in conventional transducers having MR sensors at a separate location from the writing poletips. Moreover, the magnetically permeable path is preferably formed in a low profile, highly efficient &ldquo;planar&rdquo; loop that allows for manufacturing tolerances in throat height and wear of the terminal poletips from disk contact without poletip saturation or poletip smearing. The MR layer is formed in one of the first manufacturing steps atop the substrate, so that the MR layer has a relatively uniform planar template that is free from contaminants. A preferred embodiment has a laminated yoke for improved high frequency efficiency, with the MR element situated between the yoke lamina for improved sensitivity.

Contact planar magnetoresistive head

A transducer for a hard disk drive system has a planar magnetic core and a pair of poletips that project transversely from the core for sliding contact with the disk during reading and writing. The transducer is formed entirely of thin films in the shape of a low profile table having three legs that slide on the disk, the poletips being exposed at a bottom of one of the legs for high resolution communication with the disk, the throat height of the poletips affording sufficient tolerance to allow for wear. The legs elevate the transducer from the disk sufficiently to minimize lifting by a thin air layer that moves with the spinning disk which, in combination with the small size of the thin film head allows a low load and a flexible beam and gimbal to hold the transducer to the disk. The transducer includes a loop shaped core of magnetic material that ends at the poletips, the core extending further parallel than perpendicular to the disk surface and preferably being formed of a plurality of slightly spaced ribbons of magnetic material in order to increase high frequency permeance. A high magnetic saturation layer may be formed adjoining the gap in at least the trailing poletip, in order to avoid saturation at the poletips during writing. The dimensions of the yoke adjacent to the poletips are also designed to avoid saturation at the poletips by saturating at a lower flux in the yoke than the poletips. The close relationship between the transducer and the media of the disk affords high density magnetic data storage and retrieval.

Planar magnetic ring head for contact recording with a rigid disk

An information storage system having a ring head sliding on a rigid magnetic storage disk in such close proximity that the magnetic field felt by the media layer or layers of the disk has a larger perpendicular than longitudinal component so that data is stored in a perpendicular mode. The head to media separation during writing of data to the media is a small fraction of the amagnetic gap separating the poletips of the head. Reading of data may be inductive or may be via a magnetoresistive sensor which is coupled to the magnetically permeable core of the ring head far from the poletips. The media preferably has a high perpendicular anisotropy.

Hard disk drive having ring head with predominantly perpendicular media fields

An information storage system having a ring head in such close proximity to a rigid magnetic storage disk that the magnetic field felt by the media layer or layers of the disk has a larger perpendicular than longitudinal component so that data is stored in a perpendicular mode. Reading of data is accomplished with a magnetoresistive sensor which may be coupled to the magnetically permeable core of the ring head far from the poletips, which may contact the disk. The media preferably has a high perpendicular anisotropy, and may be formed in a plurality of films with crystalline structures traversing the films.

Hard disk drive with magnetoresistive head and perpendicular media

A planar thin film magnetic head comprises an insulating substrate, a pair of insulating pedestals formed on the substrate, a top magnetic yoke having a central portion disposed over the substrate and having opposite ends supported on each of the pedestals. A conductor is provided over the top yoke central portion, and an insulating layer is disposed between the conductor and the top magnetic yoke. A bottom magnetic yoke is disposed over the conductor and has a gap in a central portion and opposite ends in contact with the top yoke ends.

Planar recording head having formed yokes

A magnetoresistive (MR) read transducer having an exchange layer adjacent a soft adjacent layer (SAL). The exchange layer generates a transverse bias field which saturates the SAL with little or no sense current.

Magnetoresistive read head having an exchange layer

Growing community of inventors

Foothill Ranch, CA, United States of America

William C Cain