Patents Assigned to Seagate Technologies
  • Laser mode hopping detection for heat-assisted magnetic recording device
    Patent number: 9984719
    Abstract: Methods and apparatuses for detecting mode hopping in a laser diode or other optical energy source in heat-assisted magnetic recording. An output power of the laser diode or other optical energy source is measured and the output power is differentiated over time to determine a rate of change. If it is determined that the rate of change exceeds a threshold value, a fault signal is asserted indicating a potential mode hopping event.
    Type: Grant
    Filed: December 2, 2015
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Robert Matousek, Todd Lammers, Jon David Trantham
  • Cascaded E-fuse switch circuits to control data backup in a storage device
    Patent number: 9984762
    Abstract: Apparatus for managing power in a data storage device, such as a solid state drive (SSD). In some embodiments, an energy management circuit supplies electrical power to a non-volatile memory (NVM). The energy management circuit has cascaded first and second E-Fuse switch circuits each with an input terminal and an output terminal. The second E-Fuse switch circuit receives input power from the first E-Fuse switch circuit used as a rail voltage for the device. The second E-Fuse switch circuit is configured to monitor the rail voltage, deactivate the first E-Fuse switch circuit responsive to the rail voltage falling below a predetermined threshold, and supply backup power to the device from a backup power source.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Nikhil Seshasayee, Keith Neil MacLean
  • Three dimensional optical memory device
    Patent number: 9984751
    Abstract: A system includes a data storage medium comprising layers, an excitation circuit, and an emitter. Each layer comprises cells arranged in a horizontal plane. Cells in different layers are arranged in a vertical plane of the data storage medium. The excitation circuit excites a layer during excitation period. Exciting the layer changes an optical property of the layer during the excitation period. The emitter emits a first and a second beam onto a first and a second cell of the layer being excited during the excitation period to orient electrical charges within the first and the second cell to a first and second oriented values and their intensity to a first and second intensity values respectively. The first and second cells maintain the first and second oriented values and the first and second intensity values after the excitation period is over or in absence of the layer being excited.
    Type: Grant
    Filed: January 25, 2017
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Joachim Ahner, David Marcus Tung
  • Apparatuses and methods for absorbing optical energy
    Patent number: 9984714
    Abstract: An apparatus including a heat sink layer and a magnetic recording layer over the heat sink layer. In addition, a thermochromic layer is over the heat sink layer, wherein the thermochromic layer includes a first optical absorbance at a first temperature and a second optical absorbance at a second temperature.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Paul M. Jones, Timothy J. Klemmer, Ruoxi Yang, Martin Giles Blaber, Xiaoding Ma, ZhaoHui Fan, Michael J. Stirniman, Yang Yang, XiaoPing Yan, Fujian Huang, Emil John Catoc Esmenda, Emir R. Kazazic, Florin Zavaliche, Hongbo Wang, Huan H. Tang, Kyoumarss Damavandi
  • Heat assisted magnetic recording (HAMR) media with thermal exchange control layer of lower curie temperature
    Patent number: 9984709
    Abstract: An apparatus is disclosed. The apparatus includes a storage layer, a thermal exchange control layer disposed over the storage layer, and a write layer disposed over the thermal exchange control layer. A Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the storage layer. The Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the write layer.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: May 29, 2018
    Assignee: Seagate Technology LLC
    Inventors: Pin-Wei Huang, YinFeng Ding, YingGuo Peng, Xiaobin Zhu, Kai-Chieh Chang, Yukiko Kubota, Timothy J. Klemmer, QiHong Wu, Ganping Ju, Jan-Ulrich Thiele, Florin Zavaliche
  • FRACTIONAL REDUNDANT ARRAY OF SILICON INDEPENDENT ELEMENTS
    Publication number: 20180143874
    Abstract: Higher-level redundancy information computation enables a Solid-State Disk (SSD) controller to provide higher-level redundancy capabilities to maintain reliable operation in a context of failures of non-volatile (e.g. flash) memory elements during operation of an SSD implemented in part by the controller. For example, a first computation is an XOR, and a second computation is a weighted-sum. Various amounts of storage are dedicated to storing the higher-level redundancy information, such as amounts equivalent to an integer multiple of flash die (e.g. one, two, or three entire flash die), and such as amounts equivalent to a fraction of a single flash die (e.g. one-half or one-fourth of a single flash die).
    Type: Application
    Filed: August 7, 2017
    Publication date: May 24, 2018
    Applicant: Seagate Technology LLC
    Inventor: Earl T. COHEN
  • Changing write coil current in response to reader instability
    Patent number: 9978403
    Abstract: Data is written to a recording medium via a read/write head. Subsequent to the writing, the data is read via a read transducer of a read/write head. An instability indicator is derived based on measurements performed while the reading the data. If the instability indicator exceeds a threshold, a current applied to a write coil of the read/write head is changed for subsequent write operations.
    Type: Grant
    Filed: February 17, 2017
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Alfredo Sam Chu, Siew Kin Chow
  • Heat assisted magnetic recording slider having a consistent close point
    Patent number: 9978405
    Abstract: A slider configured for heat-assisted magnetic recording comprises an air bearing surface (ABS), a writer, and a close point of the writer. A plurality of heat producing or dissipating components are situated a predetermined distance from a vertical plane that is normal to the ABS and aligned with the close point. A location of the writer close point remains substantially consistent irrespective of which of the plurality of heat producing or dissipating components are energized.
    Type: Grant
    Filed: February 28, 2017
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Zoran Jandric, Vasudevan Ramaswamy, Erik J. Hutchinson, John Charles Duda
  • Transparent thermocouple for heat-assisted magnetic recording device
    Patent number: 9978412
    Abstract: A slider is configured for heat-assisted magnetic recording and comprises an NFT and a transparent thermocouple configured to produce a signal indicative of temperature at the NFT. A detector can be coupled to the thermocouple and configured to detect one or both of spacing changes and contact between the slider and a magnetic recording medium.
    Type: Grant
    Filed: October 28, 2016
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Declan Macken, Patrick Carl Fletcher, Song Chen
  • Switchably activated heat transfer with magnetic fluid
    Patent number: 9976814
    Abstract: An apparatus includes a heat pipe with a fluid path. A first part of the fluid path is thermally coupled to a first region of a higher temperature and a second part of the fluid path thermally is coupled to a second region of a lower temperature. A difference between the higher temperature and the lower temperature induces a flow of a magnetic fluid in the fluid path. A switchable magnetic device is magnetically coupled to the fluid path. Activation of the switchable magnetic device reduces the flow of the magnetic fluid in the fluid path, which reduces heat transfer from the first region to the second region.
    Type: Grant
    Filed: January 27, 2015
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Kevin Arthur Gomez, Jon Trantham, David Tetzlaff, Mai A. Ghaly
  • Offset waveguide system with a mode converter and a tapered bend
    Patent number: 9978409
    Abstract: A read/write head has an input coupler that receives light at a fundamental mode from an energy source. A mode converter of the read/write head converts light from the fundamental mode to a higher-order mode. The read/write head has a bent waveguide coupled to the mode converter at an interface. The bent waveguide includes a curve with a taper. The taper nullifies the fundamental mode generated in the curve and recovers the higher-order mode at an output of the bent waveguide. A near-field transducer that receives the output of the bent waveguide is offset from the facet of the input coupler in a cross-track direction.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventor: Chubing Peng
  • Position error signal burst demodulation
    Patent number: 9979573
    Abstract: A method may generate a demodulated sine component for a sequence of samples of a servo burst window of a position error signal using a sine weight look up table and generate a demodulated cosine component for the sequence of samples of the servo burst window of the position error signal using a cosine weight look up table. The sine weight and the cosine weight look up tables may have indexes representing a phase range. The method may generate a demodulated phase component signal and a demodulated amplitude component signal for the sequence of samples of the servo burst window of the position error signal based on the demodulated sine component and the demodulated cosine component using a Coordinate Rotation Digital Computer at least in part by iteratively rotating a vector based on the demodulated sine component and the demodulated cosine component and summing angular changes in the vector.
    Type: Grant
    Filed: December 23, 2016
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Marcus Marrow, Jason Vincent Bellorado, Trung Thuc Nguyen
  • Selective nonvolatile data caching based on estimated resource usage
    Patent number: 9977732
    Abstract: The disclosure is related to systems and methods of nonvolatile data caching. In some embodiments, circuits or methods may be configured to store selected data to a nonvolatile data cache based on selection criteria. The selection criteria may be based on previous data access commands. The selection criteria may relate an amount of resources, such as time or power, needed to retrieve the selected data from a data storage medium. The selected data may be retrieved from the data storage medium and stored at the nonvolatile data cache during an idle state.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Stanton MacDonough Keeler, Steven Scott Williams, Robert William Dixon
  • Implementing scattered atomic I/O writes
    Patent number: 9977626
    Abstract: Methods, systems, and computer-readable storage media for performing scattered atomic I/O writes in a storage device. A list of block I/O write requests to be completed as an atomic unit is received from a requester with at least two of the block I/O write requests specifying non-contiguous data locations on a storage media. The plurality of block I/O write requests are buffered in a write buffer with each buffer entry marked as having an invalid state, wherein marking a buffer entry as having an invalid state prevents it from being flushed to the storage media. Upon buffering all of the plurality of block I/O writes, all of the buffer entries are marked as having a valid state at the same time. Upon marking all of the buffer entries as having a valid state, successful completion of the list of block I/O write requests is acknowledged to the requester.
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: May 22, 2018
    Assignee: Seagate Technology LLC
    Inventors: Kishore Sampathkumar, Penchala Narasimha reddy Chilakala, Parag R. Maharana, Durga Prasad Bhattarai
  • Auto-recovery of media cache master table data
    Patent number: 9971645
    Abstract: Apparatus and method for managing a media cache of a data storage device. In some embodiments, a media cache master table is maintained in a memory as a data structure having a plurality of entries that describe data sets stored in a non-volatile media cache memory. A first timecode stamp value is written to respective first and second locations in the table at the commencement of a data transfer operation to transfer data associated with the plurality of entries in the table. The first location is updated with a new, second timecode stamp value responsive to detection of an error condition that interrupts the data transfer operation. An error recovery operation is subsequently performed responsive to a detected mismatch between the timecode stamp values in the first and second locations.
    Type: Grant
    Filed: August 23, 2016
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventors: Jian Qiang, WenXiang Xie, Thein Than Zaw, Brian T. Edgar
  • Adaptively combining waveforms
    Patent number: 9971913
    Abstract: A circuit may be configured to adaptively combine two or more waveforms into a single waveform. The circuit can generate weighting factors based on received error signals, and can apply the weighting factors to the two or waveforms to be combined. In some examples, a circuit can be configured to receive input signals, receive error signals, generating a weighting coefficient based on at least some of the error signals, and determine an output signal based on the weighting coefficient and the input signals.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventors: Ara Patapoutian, Rishi Ahuja, Jason Charles Jury, Raman C Venkataramani
  • Controller for controlling the speed of a cooling device via varying speed steps, apparatus and methods
    Patent number: 9972362
    Abstract: There is disclosed a controller (120) for controlling the speed of a cooling device (118) in an electronic apparatus (100), an apparatus (100), a storage enclosure (102) and a method of configuring an apparatus (100). The controller (120) is constructed and arranged to determine a speed value for the cooling device (118) in accordance with a temperature input received from a temperature sensor (122) associated with the apparatus, the speed value being selected from a set of N speed values. The controller is arranged to control the speed of the cooling device in accordance with the selected speed value. The step between at least one pair of adjacent speed values in the set is different from the step between another pair of adjacent speed values in the set.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventor: Roger Mitchell Pimlott
  • Storage system with application to NVM address, span, and length
    Patent number: 9971547
    Abstract: Methods, systems and computer-readable storage media for determining, by a storage controller, a read unit address and encoded length information of one of the plurality of read units of a non-volatile memory (NVM) based at least in part on a page address of a particular one of a plurality of pages in a storage space address. The encoded length information may be decoded. The storage controller may determine a span specifying an integer number of the read units and a length in units having a finer granularity than the read units based at least in part on the page address. The storage controller may read data associated with the particular page based at least in part on the read unit address and the span. The storage controller may update space usage information of the NVM based at least in part on the length.
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventor: Earl T. Cohen
  • Partial zero forcing equalization
    Patent number: 9973354
    Abstract: In certain embodiments, an apparatus may comprise a circuit configured to receive a plurality of samples of an input signal. The circuit may update one or more equalizer parameters using partial zero forcing equalization. Further, the circuit may generate an equalized signal based on the plurality of samples of the input signal and the one or more equalizer parameters.
    Type: Grant
    Filed: June 25, 2016
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventors: William Michael Radich, Raman Venkataramani, Belkacem Derras, Rishi Ahuja
  • NFT with mechanically robust materials
    Patent number: 9972346
    Abstract: A recording head includes a near-field transducer proximate a media-facing surface. The near-field transducer comprises an aperture portion surrounded by walls of plasmonic material, the walls oriented normal to the media-facing surface. A notch protrudes within the aperture. The notch comprises at least one of Rh and Ir. A write pole is proximate the near-field transducer. The write pole has a back surface facing away from the media-facing surface and an aperture-facing surface proximate the aperture.
    Type: Grant
    Filed: February 27, 2017
    Date of Patent: May 15, 2018
    Assignee: Seagate Technology LLC
    Inventors: Martin Giles Blaber, Michael Allen Seigler, Michael Christopher Kautzky