公开(公告)号：US11894025B1

公开(公告)日：2024-02-06

申请号：US18053470

申请日：2022-11-08

申请人： Marvell Asia Pte Ltd

发明人： Kai Wu ,  Mats Oberg ,  Hao Fang

IPC分类号： G11B11/105 ,  G11B7/00 ,  G11B5/012 ,  G11B5/49

CPC分类号： G11B5/012 ,  G11B5/4946

摘要： A method for writing data to a magnetic data storage medium includes detecting whether the duration, before occurrence of a data transition, of data to be written exceeds a predetermined threshold, and, when the duration, before the occurrence of the data transition, of the data to be written exceeds the predetermined threshold, writing the data by applying an initial pulse and then maintaining a steady-state write current for a defined interval, and when the duration, before the occurrence of the data transition, of the data to be written is at most equal to the predetermined threshold, writing the data by applying the initial pulse without applying a steady-state write current before the data transition. The predetermined threshold may be determined by size of a magnetic bubble formed when writing a single bit to the magnetic data storage medium. A subsequent pulse may be applied following the defined interval.

公开(公告)号：US20240038261A1

公开(公告)日：2024-02-01

申请号：US17978480

申请日：2022-11-01

申请人： SAE Magnetics (H.K.) Ltd.

发明人： Ryuji FUJII ,  Shi Xiong CHEN ,  Zeng Hui ZHANG ,  Yong LEI ,  Yong Jun ZHANG

IPC分类号： G11B5/31 ,  G11B5/127 ,  G11B5/49

CPC分类号： G11B5/3169 ,  G11B5/1276 ,  G11B5/3173 ,  G11B5/49

摘要： The present disclosure discloses a magnetic head, a head gimbal assembly, a hard disk drive, and a method for processing a magnetic head. The method comprises irradiating at a fixed point proximal to the read/write part with a laser irradiation device until the read head and the write head are thermally expanded; orientating air bearing surfaces of a plurality of magnetic heads forming a magnetic strip toward a lapping surface of a lapping device after laser irradiation, holding the air bearing surfaces in place, lapping with the lapping device until the air bearing surfaces are coplanar; and disassembling the magnetic strip to obtain a lapped magnetic head. Through laser heating induced compensation, the heights of lapped read head and write head of the magnetic head meet their respective target values, ensuring the normal reading and writing of the storage medium of the magnetic disk.

公开(公告)号：US10984822B2

公开(公告)日：2021-04-20

申请号：US16928971

申请日：2020-07-14

申请人： Marvell Asia Pte, Ltd.

发明人： Mats Oberg ,  Hao Fang

IPC分类号： G11B5/09 ,  G11B5/012 ,  G11B5/31 ,  G11B5/49 ,  G11B5/00

摘要： The present disclosure describes aspects of pulse-based writing for magnetic storage media. In some aspects, a pulse-based writer of magnetic storage media determines that a string of data bits having a same polarity corresponds to a magnet longer than a threshold associated with a magnetic media writer. The pulse-based writer inserts, into the string of data bits, a transition to a polarity opposite to the same polarity of the string of data bits. The string of data bits including the inserted transition is then transmitted to the magnetic media writer to cause a write head of the writer to pulse while writing the magnet to magnetic storage media. Various aspects may also implement a control signal to mask a transition or control polarity of the magnetic media writer. By so doing, magnets may be written to the magnetic storage media more efficiently or with less distortion to neighboring tracks.

公开(公告)号：US10803899B2

公开(公告)日：2020-10-13

申请号：US16557035

申请日：2019-08-30

申请人： KABUSHIKI KAISHA TOSHIBA ,  TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION

发明人： Koji Ishii

IPC分类号： G11B5/09 ,  G11B19/04 ,  G11B5/55 ,  G11B5/49

摘要： A magnetic disk device includes a control circuit, and a disk unit including a plurality of magnetic disks, a plurality of magnetic heads configured to read or write data from or to the magnetic disks, a first actuator configured to move the magnetic heads, a plurality of second actuators each configured to move the corresponding magnetic head, and a switch circuit configured to connect the control circuit and one of the second actuators. The control circuit is configured to transmit to the disk unit an instruction in which one of the magnetic heads is specified, control one of the second actuators corresponding to the specified magnetic head to move the magnetic head via the switch circuit, and based on a signal from the one of the second actuators, determine whether an error occurs in the one of the second actuators.

公开(公告)号：US10777225B2

公开(公告)日：2020-09-15

申请号：US16018915

申请日：2018-06-26

申请人： Western Digital Technologies, Inc.

发明人： Pankaj Mehra ,  Bernd Lamberts ,  Sridhar Chatradhi ,  Jordan A. Katine

IPC分类号： G06F3/06 ,  G11B5/66 ,  G11B5/74 ,  G11B5/82 ,  G11B5/49 ,  G11B5/48 ,  G11B5/667

摘要： Disclosed herein are methods of using embedded disconnected circuits (EDC) in magnetic storage media to assist in reading data from and writing data to the magnetic storage media. A wireless activation signal is used to activate an EDC in a magnetic storage media. Once activated, the EDC may assist to record data in and/or read data from one or more memory locations of the magnetic storage media.

公开(公告)号：US10714142B2

公开(公告)日：2020-07-14

申请号：US16126422

申请日：2018-09-10

申请人： Kabushiki Kaisha Toshiba

发明人： Makoto Segawa ,  Fuyuki Tawada ,  Osamu Yoshida

IPC分类号： G11B7/00 ,  G11B20/18 ,  G11B19/04 ,  G11B5/012 ,  G11B5/49

摘要： According to one embodiment, a disk device includes a disk, a head that performs data read/write processing on a recording region of the disk, a controller that performs a media scan processing for detecting the presence or absence of a defect in a sector in the recording region of the disk in track unit. When the controller performs the media scan processing on a first sector and a second sector arranged in the track, and a third sector arranged between the first sector and the second sector, the controller performs skip processing in which the controller scans the first sector and the second sector, and does not scan the third sector.

公开(公告)号：US10109309B1

公开(公告)日：2018-10-23

申请号：US15694276

申请日：2017-09-01

申请人： Western Digital Technologies, Inc.

发明人： Pierre-Olivier Jubert ,  Kumar Srinivasan

IPC分类号： G11B5/73 ,  G11B5/708 ,  G11B5/706 ,  G11B13/08 ,  G11B5/49 ,  G11B5/738 ,  H01F10/10 ,  H01F10/12 ,  G11B5/00

摘要： A heat-assisted magnetic recording (HAMR) medium includes a perpendicular magnetic recording layer (typically a chemically-ordered FePt alloy), a seed/thermal barrier layer (typically MgO) below the recording layer, and a heat-sink layer with anisotropic thermal conductivity below the seed/thermal barrier layer. The in-plane thermal conductivity of the heat-sink layer is greater than its out-of-plane thermal conductivity. The heat-sink layer may be selected from hexagonal boron nitride (h-BN), hexagonal graphite, and the 6H polytype of hexagonal silicon carbide (6H-SiC). If the heat-sink layer is h-BN, the h-BN layer is formed on a seed layer and has its c-axis oriented out-of-plane (substantially orthogonal to the surface of the medium substrate).

公开(公告)号：US09773517B2

公开(公告)日：2017-09-26

申请号：US14685417

申请日：2015-04-13

申请人： Seagate Technology LLC

发明人： Kaizhong Gao ,  Edward Gage ,  Huaqing Yin ,  Yonghua Chen

IPC分类号： G11B21/02 ,  G11B5/49 ,  G11B5/31 ,  G11B5/012 ,  G11B5/127 ,  G11B5/48

CPC分类号： G11B5/4984 ,  G11B5/012 ,  G11B5/1278 ,  G11B5/3116 ,  G11B5/4886

摘要： A storage device includes a transducer head with multiple write elements having write poles of different sizes. For example, the transducer head may include two write poles of different width configured to write to a same surface of a storage medium. A controller of the storage device is configured to selectively engage one of the multiple write elements to write data to the storage medium.

公开(公告)号：US09437251B1

公开(公告)日：2016-09-06

申请号：US14579785

申请日：2014-12-22

申请人： Western Digital (Fremont), LLC

发明人： Steven C. Rudy ,  Luc Ving Chung ,  Christopher L. Beaudry ,  Shaoping Li ,  Jimmy J. Shen ,  Guolun Hao ,  Yingbo Zhang

IPC分类号： G11B5/39 ,  G11B5/115 ,  G11B5/29 ,  G11B33/14 ,  G11B5/60 ,  G11B5/48 ,  G11B5/49 ,  G11B5/31

CPC分类号： G11B5/3163 ,  G11B5/115 ,  G11B5/1272 ,  G11B5/29 ,  G11B5/3912 ,  G11B5/3951 ,  G11B5/3977 ,  G11B5/4886 ,  G11B5/4976 ,  G11B5/6094 ,  G11B33/1493 ,  Y10T29/49032

摘要： A method of making a magnetic head is provided. The method includes forming a first read sensor and a first electrical contact formed with a first shunt region. The method further includes forming a first mid-shield layer on the first read sensor, the first mid-shield layer being electrically connected to the first electrical contact. Additionally the method also includes forming a second mid-shield layer over the first mid-shield layer. Further, the method also includes forming a second read sensor over the second mid-shield layer, the second read sensor having a second electrical contact formed with a second shunt region electrically connected to the first shunt region.

摘要翻译： 提供一种制造磁头的方法。 该方法包括形成第一读取传感器和形成有第一分流区域的第一电触头。 该方法还包括在第一读取传感器上形成第一中间屏蔽层，第一中间屏蔽层电连接到第一电触点。 另外，该方法还包括在第一中间屏蔽层之上形成第二中间屏蔽层。 此外，该方法还包括在第二中间屏蔽层上形成第二读取传感器，第二读取传感器具有形成有电连接到第一分流区域的第二分流区域的第二电触点。

公开(公告)号：US09245556B2

公开(公告)日：2016-01-26

申请号：US14203358

申请日：2014-03-10

申请人： Western Digital Technologies, Inc.

发明人： Donald Brunnett ,  Gerardo A. Bertero ,  Shaoping Li

IPC分类号： G11B21/02 ,  G11B5/49

CPC分类号： G11B5/4969 ,  G11B5/012 ,  G11B5/4886 ,  G11B5/4976 ,  G11B5/5539

摘要： A disk drive is disclosed comprising a disk comprising a plurality of tracks, and a head comprising at least three read elements including a first read element, a second read element, and a third read element. When the head is within a first radial band of the disk, data recorded on the disk is detected using the first read element and the second read element. When the head is within a second radial band of the disk different from the first radial band, data recorded on the disk is detected using the first read element and the third read element. The first read element is substantially aligned down-track with the third read element when the head is over a first radial location of the disk.

摘要翻译： 公开了一种磁盘驱动器，包括包括多个磁道的磁盘，以及包括至少三个读取元件的磁头，包括第一读取元件，第二读取元件和第三读取元件。 当磁头位于磁盘的第一径向带内时，使用第一读取元件和第二读取元件检测记录在磁盘上的数据。 当磁头位于不同于第一径向磁带的盘的第二径向带内时，使用第一读取元件和第三读取元件检测记录在盘上的数据。 当磁头位于磁盘的第一径向位置时，第一读取元件与第三读取元件基本上对准。