公开(公告)号：US10755736B2

公开(公告)日：2020-08-25

申请号：US16524544

申请日：2019-07-29

Applicant: Seagate Technology LLC

Inventor： Xiong Liu ,  Lihong Zhang ,  PengBoon Khoo

IPC: G11B5/00 ,  G11B5/596 ,  G11B20/10 ,  G11B20/12 ,  G11B5/66

Abstract: A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

公开(公告)号：US10734033B2

公开(公告)日：2020-08-04

申请号：US16694719

申请日：2019-11-25

Applicant: Seagate Technology LLC

Inventor： Jian Qiang ,  Xiong Liu ,  Choon Wei Ng ,  Sangyun Jung

IPC: G11B5/596 ,  G11B27/36 ,  G11B20/10 ,  G11B20/12 ,  G06F3/06 ,  G11B5/012 ,  G06F12/0871

Abstract: Methods and systems that reduce off-track write retry operations in shingled magnetic recording systems. In one implementation, the method includes writing data to an initial track, determining which side of the initial track is a shingled side, calculating a percentage of position error signal (PES) at a shingled side end of the initial track (PES1) when an off-track write operation occurs, determining whether the PES1 meets a first pre-determined threshold, continue writing data to a second track responsive to determining the PES1 is below a first pre-determined threshold, calculating a percentage of PES at a shingled side end of the second track (PES2), determining whether a combined value of PES1 and PES2 is above a second predetermined threshold to determine a probability value of the initial track being erased, and continue writing to a third track if the combined value is below the second predetermined threshold.

公开(公告)号：US20190341080A1

公开(公告)日：2019-11-07

申请号：US15970758

申请日：2018-05-03

Applicant: Seagate Technology LLC

Inventor： Christopher M. Woldemar ,  YiChao Ma ,  Xiong Liu ,  Li Hong Zhang

IPC: G11B33/14 ,  G11B33/12 ,  G11B33/02

Abstract: A storage container includes a base housing member coupled to an inner cover and including an inner cavity. The storage container further includes an outer cover coupled to the base housing member and covering the inner cover. A rack assembly includes a plurality of storage devices and is mounted within the inner cavity.

公开(公告)号：US10446182B1

公开(公告)日：2019-10-15

申请号：US16008760

申请日：2018-06-14

Applicant: Seagate Technology LLC

Inventor： Lihong Zhang ,  Xiong Liu ,  Samuel Swee Chuan Gan

IPC: G11B11/105 ,  G11B5/60 ,  G11B5/48 ,  G11B5/00

Abstract: Apparatus and method for heat assisted magnetic recording (HAMR). In some embodiments, a write element has a magnetic write coil that writes a magnetic pattern to a recording layer of a data recording surface. A light delivery mechanism imparts heat in the form of electromagnetic energy to the data recording layer during operation of the write element. A radiation detector detects radiation power emitting from the recording layer responsive to the operation of the light delivery mechanism. A control circuit determines a direct temperature of the recording layer responsive to the detected radiation power, and as necessary, adjusts a power input to the light delivery mechanism responsive to the determined temperature. The radiation detector may be an infrared photodetector with a graphene-based detection layer. The photodetector may be disposed between a write pole and a return pole of the write element.

公开(公告)号：US10416729B2

公开(公告)日：2019-09-17

申请号：US15276987

申请日：2016-09-27

Applicant: Seagate Technology LLC

Inventor： Hao Sun ,  Aravind Pitty ,  Xiong Liu ,  Ling Ling Zhang

IPC: G06F1/18 ,  G11B33/02 ,  G11B33/12

Abstract: A hard disk drive mounting assembly that includes a disk drive assembly having a base structure that includes a screw hole and a damping insert at least partially surrounding the screw hole. The disk drive assembly further includes a threaded insert positioned in the screw hole of the damping insert.

公开(公告)号：US20190250887A1

公开(公告)日：2019-08-15

申请号：US15894116

申请日：2018-02-12

Applicant: Seagate Technology LLC

Inventor： Xiong Liu ,  Lihong Zhang ,  WenXiang Xie ,  Quan Li

IPC: G06F7/58

Abstract: Apparatuses and methods disclosed herein relate to detecting a signal generated by a spin torque oscillator (STO). The signal is outputted, wherein the signal includes a direct current (DC) component, a wide bandwidth noise component, and an STO oscillating radio frequency (RF) component. The signal is filtered, wherein the filtering removes the DC component and the STO oscillating RF component, leaving the wide bandwidth noise component. A value of the wide bandwidth noise component is converted into a binary value, and a bit from the binary value is selected and combined with another bit to form a random number.

公开(公告)号：US20190102307A1

公开(公告)日：2019-04-04

申请号：US15719957

申请日：2017-09-29

Applicant: Seagate Technology LLC

Inventor： Andrew Michael Kowles ,  Xiong Liu ,  Mark Gaertner ,  Kai Yang ,  WenXiang Xie ,  Jiangnan Lin

IPC: G06F12/0871 ,  G06F12/0875 ,  G06F12/0811

Abstract: In accordance with one implementation, a method for mitigating cache transfer time entails reading data into memory from at least two consecutive elliptical data tracks in a main store region of data storage and writing the data read from the at least two consecutive elliptical data tracks to a spiral data track within a cache storage region.

公开(公告)号：US10249332B1

公开(公告)日：2019-04-02

申请号：US16013193

申请日：2018-06-20

Applicant: Seagate Technology LLC

Inventor： Xiong Liu ,  Lihong Zhang ,  PengBoon Khoo

IPC: G11B5/09 ,  G11B5/596 ,  G11B20/10 ,  G11B5/00

Abstract: A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

公开(公告)号：US10192580B1

公开(公告)日：2019-01-29

申请号：US15971284

申请日：2018-05-04

Applicant: Seagate Technology LLC

Inventor： Xiong Liu ,  Quan Li ,  Ralph William Cross

IPC: G11B15/02 ,  G11B11/105 ,  G11B20/10 ,  G11B5/09 ,  G11B5/012

Abstract: A sequence of symbols is generated to describe a set of write data, the symbols having a length of nT, where T is a channel clock rate and n is an integer over a predetermined range. Bi-directional write currents are applied to a write pole to record the sequence of symbols to a magnetic storage medium. The write pole has an effective footprint with a downtrack length of mT, where m is an integer. The write currents are switched between a first rail current and a second rail current for alternating symbols, the write currents further transitioning to an intermediate current value for at least one channel clock period for symbols longer than 1T. Write currents are applied to the write pole when recording symbols having a length longer than mT using the effective footprint of the write pole as an interval.

公开(公告)号：US10176843B2

公开(公告)日：2019-01-08

申请号：US15883934

申请日：2018-01-30

Applicant: SEAGATE TECHNOLOGY LLC

Inventor： Xiong Liu ,  MingZhong Ding ,  ChuenBuan Lee

IPC: G11B5/596 ,  G11B20/18 ,  G11B5/39

Abstract: Systems and methods for determining an occurrence of non-operation shock (NOS) in a disc drive are described. Such determining may be used to determine whether or not the disc drive should be recalibrated or compensated to account for changes induced by NOS. Determining NOS may be based at least in part on a harmonic of the spindle of the disc drive other than the first harmonic, such as a third harmonic of the spindle. In some embodiments, determining NOS may be based on the first harmonic of the spindle and at least one other harmonic of the spindle.