Western Digital Technologies, Inc.

Seagate Technology Incorporated

Samsung Electronics Co., Ltd.

The Penn State Research Foundation

Maxtor Corporation

Yanning Liu

Wing Chun Shum

Kia Moh Teo

John Edward Scura

Tzong-Shii Pan

Yih-Jen Dennis Chen

Guoxiao Guo

Joey Martin Poss

Charles A Park

Ryan P Mayo

Scott A Ottele

Richard Conway

Xin Ru Wang

Erhard Theodor Schreck

Timothy A Ferris

Duc T Phan

Chuanwen Ji

Yi Lu

Yanchu Xu

Nathan J Santee

Mukund Vijay

David Marcus Tung

Yu Sun

Hiroyasu Tsuchida

Jaesoo Byoun

Michael C McGrath

Hitoshi Shindo

David E Fowler

Dean V Dang

Manoj Keshavan

Gregory Tran

Yanan Huang

Jianghong Ding

Mark Heimbaugh

Seong Woo Kang

Siddhesh Vivek Sakhalkar

Mukesh Patel

Norman D Gardner

Brian P Schott

Ming Ying Wang

Kon-Well Wang

Seungman Chang

Toviah N Hirschberg

Andrew H Tong

Kathryn Tao

Sivabalan Ganisen

Mike Leis

Jong Hyun Lee

Rainer H Laatsch

Example circuits, data storage devices, and methods to provide parallel self-servo write in a data storage device are described. The data storage device may include multiple heads actuated over respective surfaces of storage media and at least two preamplifiers and read paths to a channel circuit. Control circuitry may select heads connected through different preamplifiers for parallel self-servo write and receive read signals from the selected heads in parallel. These read signals, which may be based on self-servo write reference spirals previously written to the storage media, may be used to determine respective position error signals for the two heads and control their respective positions with corresponding control signals to a shared voice control motor and respective micro and/or milli actuators on the arms supporting the heads.

Parallel self-servo write circuitry in a data storage device

Example storage preamplifier circuits, data storage devices, and methods for parallel self-servo write are described. The data storage device may include a pair of preamplifier circuits electrically connected to respective banks of read heads actuated over a storage media surfaces. In read/write operation, each preamplifier circuit may selectively and sequentially provide read signals from a selected head to a pair of read channel interfaces. In self-servo write operation, each preamplifier circuit may selectively and in parallel provide read signals from a selected head in their corresponding banks of read heads to the pair of read channel interfaces. For example, the pair of read channel interfaces for two-dimensional magnetic recording may receive read signals from one read sensor in a head in the first bank of heads and another read sensor for another head in the second bank of heads.

Preamplifier circuit for parallel self-servo write

Example control circuitry, data storage devices, and methods for parallel self-servo write in a data storage device are described. The data storage device may include multiple heads actuated over different surfaces of a data storage device and receive read signals from two different heads over two different surfaces in parallel. Position error signals may be determined from each read signal and corresponding position compensation values may be determined for their respective microactuators. Application of these compensation values may maintain their relative positions for parallel writing of servo tracks based on their respective spiral reference patterns and TPI settings.

Parallel self-servo write in a data storage device

Control circuitry is disclosed configured to control inner fine actuators of a first plurality of inner actuator arms and independently control a first outer fine actuator of a first outer actuator arm. Inner fine actuators of a second plurality of inner actuator arms are controlled while independently controlling a second outer fine actuator of a second outer actuator arm. Each actuator arm comprises at least one head configured to access a disk surface of a disk.

Data storage device independently driving outer and inner fine actuators

A data storage device is disclosed comprising a plurality of disks each comprising a top disk surface and a bottom disk surface. A plurality of inner actuator arms each comprise a first inner fine actuator configured to actuate a top head over one of the top disk surfaces and a second inner fine actuator configured to actuate a bottom head over one of the bottom disk surfaces. A first outer actuator arm comprises a first outer fine actuator configure to actuate a top head over a top disk surface of a top disk, and a second outer actuator arm comprises a second outer fine actuator configured to actuate a bottom head over a bottom disk surface of a bottom disk, wherein the inner fine actuators are controlled independent from the outer fine actuators.

A multiple-actuator hard disk drive includes multiple head-stack assemblies (HSA) and a disk stack including a shared disk operated upon by both of the HSAs. Generally to provide more space between the HSAs such as for routing electrical traces, the distance between the shared disk and each of the upper and lower adjacent disks is greater than the distance between each of the upper and lower adjacent disks and the next adjacent disk. Each arm tip of the arms operating upon the shared disk may be thicker than other arm(s) operating upon other disks in the stack, so that the z-height between each head slider and corresponding disk surface is maintained in view of the differing disk spacing. Suspension tails for the arms that operate on the shared disk may be biased to offset away from the shared disk to provide for more clearance between the HSAs.

Shared disk configuration in a multiple actuator hard disk drive

An approach to a head gimbal assembly, such as for a hard disk drive, includes an offset swage plate coupling a suspension to one side of an actuator arm and another offset swage plate coupling another suspension to an opposing second side of the actuator arm. Each offset swage plate includes a main body, a swage through-hole through a first lateral or longitudinal side of the main body, a swage boss around the perimeter of the swage through-hole and extending substantially normal to the main body, and a clearance through-hole through an opposing second lateral or longitudinal side of the main body, the clearance through-hole having no swage boss. Each offset swage plate is configured in the assembly in a position opposing the other, such that the corresponding swage bosses are positioned on different lateral/longitudinal sides of the arm tip so that there is no coaxial swage boss buildup.

Offset swage baseplate for stacked assembly

An approach to a head gimbal assembly (HGA), such as for a hard disk drive, includes a swage plate assembly coupling a suspension to one side of an actuator arm, where the swage plate assembly includes a baseplate having a through-hole and a swage boss insert comprising a flange and a swage boss extending from the flange through the baseplate through-hole. The HGA is configured such that the baseplate is positioned between the flange and the actuator arm, such that a distal surface of the flange is the surface closest to a corresponding recording medium, whereby the thickness of the suspension is effectively recessed within the material dimensional buildup of the other parts and a greater clearance is provided between the suspension and the recording medium.

Swage plate assembly with swage boss insert

Disclosed herein is an apparatus that comprises an actuator arm that is pivotably connectable to a pivot post at a proximal end. The actuator arm extends linearly along a first axis from the proximal end to a distal end. The apparatus also comprises a lift tab that comprises an elongate member. The elongate member comprises a proximal end, coupled to the distal end of the actuator arm, and a distal end. The elongate member extends linearly along a second axis from the proximal end to the distal end. The second axis intersects the first axis to define an angle between the first axis and the second axis. The distal end of the elongate member is configured to engage an incline member when the actuator arm is in an unload position to lift the actuator arm.

Angled and elongate lift tab for magnetic storage device

A data storage device is disclosed comprising a voice coil motor (VCM) and a secondary actuator configured to actuate a head over a disk. A position error signal (PES) is generated based on servo data recorded on the disk, and a first control signal is generated based on the PES. The PES is adjusted based on the first control signal to generate a first adjusted PES, and a second control signal is generated based on the first adjusted PES. A secondary actuator control signal is generated based on the first control signal and the second control signal, wherein the secondary actuator control signal is applied to the secondary actuator. The first adjusted PES is adjusted based on the second control signal to generate a second adjusted PES, and a VCM control signal is generated based on the second adjusted PES, wherein the VCM control signal is applied to the VCM.

Data storage device controlling dual stage actuator with triple stage servo loop

A head suspension assembly for a disk drive includes a load beam and a laminated flexure that comprises a stainless steel layer, a copper trace layer, and a dielectric layer between the stainless steel layer and the copper trace layer. The laminated flexure includes a flexure tail that extends away from the load beam to a flexure tail terminal region. The copper trace layer includes a plurality of flexure bond pads in the flexure tail terminal region. The stainless steel layer includes a plurality of backing islands in the flexure tail terminal region. Each of the plurality of backing islands is aligned with a corresponding one of the plurality of flexure bond pads. A noble metal layer is disposed on the plurality of backing islands.

Disk drive head suspension tail with a noble metal layer disposed on a plurality of structural backing islands

A head gimbal assembly (HGA) for a disk drive includes a load beam, a laminated flexure attached to the load beam, and a head attached to the laminated flexure. The laminated flexure includes a tail for electrical connection between the head and a flex cable of a head stack assembly. The laminated flexure tail may include a plurality of conductive traces, a structural layer, and a dielectric layer there between, and may be disposed partially within a slot of an actuator arm. A first insulative cover layer is disposed on the plurality of conductive traces. A plurality of stand-off islands is disposed on the first insulative cover layer, and over at least one of the plurality of conductive traces (e.g. the writer traces). At least one of the plurality of stand-off islands is at least partially disposed between the first insulative cover layer and the inner slot surface.

Head gimbal assembly having a flexure tail with cover layer standoff islands

A novel suspension assembly includes a suspension assembly mounting plate, a microactuator mounting structure extending from the suspension assembly mounting plate, a load beam extending from the microactuator mounting structure, and a laminated flexure attached to the load beam. The laminated flexure includes a tongue that has a read head bonding surface. The suspension assembly includes a stainless steel surface having a gold coating, and a piezoelectric microactuator attached to the microactuator mounting structure and electrically connected to the gold coating.

Suspension assembly having a microactuator electrically connected to a gold coating on a stainless steel surface

A head gimbal assembly for a disk drive includes a flexure tail terminal region having flexure bond pads in electrical communication with the head. Each of the flexure bond pads is aligned with one of a plurality of flexible printed circuit (FPC) bond pads. An anisotropic conductive film is disposed between the FPC and the flexure tail terminal region. The flexure tail terminal region overlaps the anisotropic conductive film in a bonding area. Each of the flexure bond pads is bonded to one of the plurality of FPC bond pads by the anisotropic conductive film in a bonding area. A conductive layer of the flexure tail terminal region includes an exposed conductive ground pad that is disposed outside of the bonding area, and/or disposed outside of an application area of a thermode tool that is pressed against the flexure tail terminal region during the bonding process.

Disk drive head suspension tail with ground pad outside of bonding region

Growing community of inventors

San Ramon, CA, United States of America

Yanning Liu