Seagate Technology Incorporated

Other

National University of Singapore

Qiang Bi

Xiong Liu

MingZhong Ding

Kian Keong Ooi

Kevin Arthur Gomez

Xiang Lu

KianKeong Ooi

ChoonKiat Lim

Jimmy Pang

YangQuan Chen

WenJun Cao

Jian Qiang

UttHeng Kan

Choon Kiat Lim

Joshua Ward Christensen

Edmun ChianSong Seng

BengWee Quak

WingKong Chiang

Song Wee Teo

LeeLing Tan

WeiMing Yeow

GuoQing Zhang

Jose Mari Toribio

Tze Pin Chin

Tao Zhang

TaiVie Chiang

Ricardo SoonLian Lim

WenXiang Xie

Jimmy Tze Ming Pang

Wei Chen Lau

Phan Linh Nguyen

Heather Lee Mallett

Renee Depew

Stephen Kow Chiew Kuan

Chi Sern Georgie Tan

David Allan Thorsvik

Tim Rausch

Gabor Szita

Lealon Ray McKenzie

Raye Abdoulie Sosseh

Jin Quan Shen

Evgeny R Kharisov

ShuangQuan Min

Utt Heng Kan

Lou Supino

Brent Jay Harmer

Patrick TaiHeng Wong

Aik Chuan Lim

Chuen Buan Lee

WeiSung Lee

JiaHong Shu

Christopher M Woldemar

Chang Chieh Hang

Zai Yu Nang

Chi Sern Tan

TzeMing Jimmy Pang

BengSee Lim

Hui Wang

Qing-Guo Wang

Kevin A Gomez

MengEng Lye

ShihMing Lau

Patrick TaiHeng

MingZhong Dong

Wen-Jun Cao

Seow Zhao Li

KokHiang Cheong

Yong Y Yang

A device includes a servo controller that includes or that is coupled to memory. The memory stores multiple distinct disturbance control schemes. The servo controller is configured to select and implement one of the disturbance control schemes in response to receiving a command from a host. The servo controller can be implemented on a system on a chip.

Adaptable servo controllers

The technology disclosed herein pertains to a system and method for managing write failures in a disc drive. Implementations disclosed herein provide a method including monitoring write fault events per sector for a storage device, in response to a write fault event, updating a write fault repeat count table, wherein the repeat count table tracks a number of write fault repeat counts per sector, comparing a write fault repeat count for a sector to a predetermined threshold write fault repeat count, and in response to determining that the write fault repeat count for a sector is above the predetermined threshold write fault repeat count, performing a write-reassign operation.

System and method for write-retry management

The technology disclosed herein provides a method for generating an on-cylinder limit (OCLIM), the method including performing servo certification of a plurality of drives in a storage device to generate servo adaptive parameters (SAPs) by heads, generating a plurality of read adjust parameters (RAPs) by heads for the plurality of drives, generating an interim OCLIM value based on the SAPs by heads and RAPs by zones, and operating a disc drive write element using the interim OCLIM value.

Flexible on-cylinder limit for drive performance management

A data storage drive includes a servo loop for positioning a head over a disc. The servo loop includes a sensor, located in the head, that senses servo information located on the disc and produces a servo signal therefrom. The servo signal is combined with a reference signal to produce a raw position error signal (PES). The servo loop further also at least one phase-matching disturbance attenuation (PMDA) filter that receives the raw PES as an input and responsively outputs a vibration-cancellation signal, which, when combined with the raw PES, cancels vibration-induced disturbance from the raw PES, thereby producing a refined PES. A servo controller receives the refined PES and responsively produces a servo control signal. An actuator moves the head in response to receiving the servo control signal.

Attenuation of vibration-induced disturbances in a data storage device

The disclosed technology provides a system and method that improves interlaced magnetic recording (IMR) data throughput in vibration in storage systems. In one implementation, a method includes determining whether there are write retry operations in the IMR storage device, determining whether bottom track caching space is available responsive to determining whether there are write retry operations in the IMR storage device, performing a vibration detection scheme to identify vibration events responsive to determining whether bottom track caching space is available, determining if a number of vibration events is above a predetermined threshold, and writing data to available bottom track caching space responsive to determining if the number of vibration events is above a predetermined threshold.

Interlaced magnetic recording storage system

Apparatus and method for managing data transfers in a data storage device with rotational media that can be rotated at different speeds. In some embodiments, a non-volatile main memory is formed on a rotatable medium accessed by a moveable data transducer. A media cache provides a non-volatile data storage area. A control circuit directs writes to the main memory as the medium is rotated at a first speed and directs reads from the main memory as the medium is rotated at a higher, second speed. Writes during the rotation of the medium at the second speed are directed to the media cache instead of to the main memory so that no data are written to the main memory at the second speed. The media cache may also be located on the medium or may be formed from solid-state semiconductor memory.

Multi-speed data storage device with media cache for high speed writes

An apparatus includes a disk locked clock system and a feedforward microactuator compensator. The disk locked clock system is configured to estimate a timing error and generate a timing error signal. The feedforward microactuator compensator is configured to generate a microactuator compensation signal, without use of a vibration sensor signal, in response to the timing error signal.

Vibration compensation using disk locked clock error

Systems and methods for compensating for magnetoresistive (MR) jog offset direct current (DC) drift in a disc drive are described. In one embodiment, a method may include determining an occurrence of NOS, for example, by monitoring disc slip, to determine when the method should proceed. An MR jog offset DC drift amount is determined for each head of the disc drive. One of several approaches may be employed for determining the MR jog offset DC drift amount. By determining an MR jog offset DC drift amount for each head, a compensation profile is determined for the drive. The determined compensation profile may then be used during operation of the disc drive to compensate for the DC drift. One of several approaches may be employed for compensating based on the compensation profile.

Direct current magnetoresistive jog offset compensation

An apparatus includes a microactuator controller configured to generate a microactuator control signal, a feedforward microactuator compensator configured to generate a microactuator compensation signal, and a microactuator model filter configured to filter a modified microactuator control signal. The microactuator compensation signal is configured to be injected into the microactuator control signal to generate the modified microactuator control signal. The microactuator model filter generates a filtered modified microactuator control signal and injects the filtered modified microactuator control signal into a position error signal to generate a modified position error signal.

Disturbance compensation for dual-stage servo system using vibration sensor

An apparatus comprises a heat-assisted magnetic recording drive which includes an enclosure having a base and a cover. The drive includes a magnetic recording disk and a head gimbal assembly proximate one of the base and the cover. The HGA supports a slider assembly comprising a laser diode unit. The LDU projects away from the HGA towards one of the base and the cover. An arcuate channel is provided in one of the base and the cover and dimensioned to receive a distal portion of the LDU. The channel has a length that accommodates the distal portion of the LDU along a stroke of the HGA.

Heat-assisted magnetic recording drive enclosure with arcuate channel for accommodating laser diode unit

Certain exemplary aspects of the present disclosure are directed towards apparatuses and methods which mitigate the effect of speaker vibration on a disc drive. Audio associated with a speaker output is detected and triggers the generation of an output signal indicative of speaker vibration associated with such an audio output of a speaker. A magnetoresistive transducer of the disc drive is positioned relative to a storage medium based on the output signal, a target data storage location in the storage medium from which data is to be accessed via the positioning, and the position of the transducer. The output signal mitigates the effect of the speaker vibration on the transducer.

Disc drive speaker vibration mitigation

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Singapore, Singapore

Qiang Bi