Patents by Inventor Wenzhong Zhu

Wenzhong Zhu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9842619
    Abstract: A set of consecutive user data wedges are each located between consecutive servo wedges of a heat-assisted recording medium. Test data is written at least every other one of the consecutive data wedges using different laser power values. Based on reading the test data, a nominal laser power is selected for use by the read/write head.
    Type: Grant
    Filed: April 27, 2016
    Date of Patent: December 12, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Alfredo Sam Chu, Wenzhong Zhu, Tim Rausch
  • Patent number: 9842047
    Abstract: A storage device controller addresses consecutively-addressed portions of incoming data to consecutive data tracks on a storage medium and writes the consecutively-addressed portions to the consecutive data tracks in a non-consecutive track order. In one implementation, the storage device controller reads the data back from the consecutive data tracks in a consecutive address order in a single sequential read operation.
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: December 12, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Tim Rausch, Edward Gage
  • Patent number: 9830935
    Abstract: An apparatus that includes a read sensor having a bearing surface and first and second free layers that are separated by an intermediate structure. The first FL includes multiple segments, with each segment having a width at the bearing surface. A sum of the widths of different ones of the multiple segments is a first width of the first FL. The second FL is unsegmented and has a second width at the bearing surface that is different from the first width of the first FL. The read sensor also includes a first terminal connected to a first one of the multiple segments of the first FL, and a second terminal connected to a second one of the multiple segments of the first FL. A third terminal is connected to the second FL. Control circuitry applies a bias current from either the first or second terminal to the third terminal.
    Type: Grant
    Filed: August 10, 2016
    Date of Patent: November 28, 2017
    Assignee: Seagate Technology LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Edward Gage
  • Publication number: 20170330591
    Abstract: A storage device includes a storage controller configured to operate a heat-assisted magnetic recording head to write data to a band of consecutive data tracks in a consecutive track order while selectively alternating a power level of the heat source when writing to some data tracks of the band.
    Type: Application
    Filed: May 13, 2016
    Publication date: November 16, 2017
    Inventors: Steven Granz, Edward Gage, Alfredo Chu, Wenzhong Zhu
  • Publication number: 20170330587
    Abstract: A storage device controller is configured to select one of multiple written track widths for a storage location based on a write attribute of data to be recorded at the storage location. According to one implementation, the storage device controller is further configured to select a power level for a heat-assisted magnetic recording (HAMR) device based on the write attribute.
    Type: Application
    Filed: August 3, 2017
    Publication date: November 16, 2017
    Inventors: Kaizhong Gao, Wenzhong Zhu, Tim Rausch, Edward Gage
  • Patent number: 9818438
    Abstract: A system may compensate for skew in a patterned medium, such as but not limited to a self-assembling bit patterned medium, with a write pole separated from a data storage medium by an air bearing. The write pole being connected to a controller. The data storage medium can have a plurality of magnetic islands arranged in data tracks with each data track having a track center. The write pole may be selectively shifted from the track center by the controller to compensate for a skewed write pole configuration.
    Type: Grant
    Filed: September 30, 2016
    Date of Patent: November 14, 2017
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Gary E. Hillukka, Bin Huang
  • Patent number: 9818445
    Abstract: Implementations described and claimed herein includes a storage device comprising a plurality of readers, including a first subset of readers configured to read a first subset of tracks and a second subset of readers configured to read a second subset of tracks, the first subset of tracks being wider than the second subset of tracks. In another implementation, the readers in the first subset of readers are wider than the readers in the second subset of readers. The wider readers may be configured to recover servo information and the narrow readers may be configured to recover data information. The storage devices may include two-dimensional magnetic recording, conventional perpendicular magnetic recording, shingled magnetic recording, multi-sensor magnetic recording, and interlaced magnetic recording.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: November 14, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Mehmet F. Erden, Kenneth A. Haapala, Wei Tian, Edward Gage
  • Patent number: 9747942
    Abstract: A storage device controller is configured to select one of multiple written track widths for a storage location based on a write attribute of data to be recorded at the storage location. According to one implementation, the storage device controller is further configured to select a power level for a heat-assisted magnetic recording (HAMR) device based on the write attribute.
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: August 29, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Tim Rausch, Edward Gage
  • Patent number: 9747943
    Abstract: A storage device includes a controller that directs incoming data to a storage location based on a capacity of a region or surface of a magnetic disc. According to one implementation, the storage device controller writes new data to data tracks in a first series of data tracks on the magnetic disc until a capacity condition is satisfied. Once the capacity condition is satisfied, the storage device controller writes new data to a second series of data tracks on the storage medium that are interlaced with data tracks of the first series.
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: August 29, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kaizhong Gao, Edward Gage
  • Publication number: 20170243609
    Abstract: Systems and methods for determining a relationship between write fault threshold and temperature are described. The systems and methods include measuring an operating temperature of the storage device, determining a current operating temperature of the storage device, determining whether the current operating temperature of the storage device satisfies a temperature threshold, and upon determining the current operating temperature of the storage device satisfies the temperature threshold, modifying a write fault threshold associated with a data track of the storage device.
    Type: Application
    Filed: May 10, 2017
    Publication date: August 24, 2017
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kenneth A. Haapala, Bin Huang
  • Patent number: 9734862
    Abstract: A first tone is written at a first frequency to outer tracks that surround an inner track of a magnetic recording medium. A second tone is written at a second frequency different from the first frequency to the inner track. The first and second frequencies are both lower than a frequency of an AC erase signal. A crosstrack profile of the inner track is determined based on reading amplitude of the second frequency via the read/write head.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: August 15, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Alfredo Sam Chu, Wenzhong Zhu, Siew Kin Chow, Franklin P. Martens
  • Patent number: 9728206
    Abstract: A storage device includes a transducer head including a first write element configured to write data at a first write width and a second write element configured to write data at a second write width less than the first write width. According to one implementation, the first write element writes data at a first linear density and to alternating data tracks and the second write element writes data at a second linear density and to data tracks interlaced with the alternating data tracks.
    Type: Grant
    Filed: April 14, 2015
    Date of Patent: August 8, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Edward Gage
  • Publication number: 20170206927
    Abstract: A storage device includes a storage medium having a plurality of data tracks. At least one data track of the plurality of data tracks includes a number of super parity sectors. The number of super parity sectors selected for the at least one data tracks is selected based on a distance between an inner diameter of the storage medium and the data track. The number of super parity sectors provides error correction code for the at least one data track.
    Type: Application
    Filed: March 31, 2017
    Publication date: July 20, 2017
    Inventors: Wenzhong Zhu, Kaizhong Gao, Tim Rausch, Edward Charles Gage
  • Publication number: 20170200468
    Abstract: Implementations described and claimed herein includes a storage device comprising a plurality of readers, including a first subset of readers configured to read a first subset of tracks and a second subset of readers configured to read a second subset of tracks, the first subset of tracks being wider than the second subset of tracks. In another implementation, the readers in the first subset of readers are wider than the readers in the second subset of readers. The wider readers may be configured to recover servo information and the narrow readers may be configured to recover data information. The storage devices may include two-dimensional magnetic recording, conventional perpendicular magnetic recording, shingled magnetic recording, multi-sensor magnetic recording, and interlaced magnetic recording.
    Type: Application
    Filed: January 12, 2016
    Publication date: July 13, 2017
    Inventors: Wenzhong Zhu, Mehmet F. Erden, Kenneth A. Haapala, Wei Tian, Edward Gage
  • Patent number: 9704519
    Abstract: For each head in a collection of heat-assisted magnetic recording read/write heads, a reader width and a writer width is measured. A predicted life is determined for each head based on the respective reader width and writer width. In a first set of drives having relatively fewer heads per drive, a first subset of the heads having a higher value of the predicted life are used. In a second set of drives having relatively more heads per drive, a second subset of the heads having a lower value of the predicted life are used.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: July 11, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Edward Charles Gage, Alfredo Sam Chu
  • Patent number: 9691418
    Abstract: Systems and methods for determining a relationship between write fault threshold and temperature are described. The systems and methods include measuring an operating temperature of the storage device, determining a current operating temperature of the storage device, determining whether the current operating temperature of the storage device satisfies a temperature threshold, and upon determining the current operating temperature of the storage device satisfies the temperature threshold, modifying a write fault threshold associated with a data track of the storage device.
    Type: Grant
    Filed: December 21, 2015
    Date of Patent: June 27, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kenneth A. Haapala, Bin Huang
  • Publication number: 20170178672
    Abstract: Systems and methods for determining a relationship between write fault threshold and temperature are described. The systems and methods include measuring an operating temperature of the storage device, determining a current operating temperature of the storage device, determining whether the current operating temperature of the storage device satisfies a temperature threshold, and upon determining the current operating temperature of the storage device satisfies the temperature threshold, modifying a write fault threshold associated with a data track of the storage device.
    Type: Application
    Filed: December 21, 2015
    Publication date: June 22, 2017
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kenneth A. Haapala, Bin Huang
  • Patent number: 9679601
    Abstract: A storage device includes a data degradation management module that tracks a risk of data degradation by incrementing a track write counter of a first data track responsive to each data write command to a second data track, such as a data track directly adjacent to the first data track. If a count of the track write counter exceeds a count threshold, one or more post-write scan operations are performed to assess and/or repair data degradation of the first data track.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: June 13, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Tim Rausch, Edward Gage
  • Patent number: 9679597
    Abstract: An apparatus and method involves a writer configured for heat-assisted magnetic recording of data to a magnetic storage medium. A controller is coupled to the writer. The controller and writer are configured to write data to a plurality of concentric bands of the medium each comprising a plurality of partially overlapping narrow data tracks and a wide track. The wide tracks of successive bands are positioned adjacent to one another with no intervening narrow data track therebetween.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: June 13, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Alfredo Sam Chu
  • Publication number: 20170148484
    Abstract: A storage device includes a controller that directs incoming data to a storage location based on a capacity of a region or surface of a magnetic disc. According to one implementation, the storage device controller writes new data to data tracks in a first series of data tracks on the magnetic disc until a capacity condition is satisfied. Once the capacity condition is satisfied, the storage device controller writes new data to a second series of data tracks on the storage medium that are interlaced with data tracks of the first series.
    Type: Application
    Filed: February 8, 2017
    Publication date: May 25, 2017
    Inventors: Wenzhong Zhu, Kaizhong Gao, Edward Gage