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: 11011189
    Abstract: A read channel is configured to obtain an analog readback waveform from a magnetic recording medium of a disk drive at a sampling rate of one sample per one written bit. A buffer is coupled the read channel. Circuitry is configured to inject a plurality of different phase offsets into the read channel for each of a plurality of revolutions of the medium. The circuitry is also configured to store, in a buffer, an amplitude of the readback waveform for each of the different phase offsets. The circuitry is further configured to generate an oversampled readback waveform using the amplitudes stored in the buffer.
    Type: Grant
    Filed: April 21, 2020
    Date of Patent: May 18, 2021
    Assignee: Seagate Technology LLC
    Inventors: Drew Michael Mader, Wenzhong Zhu
  • Patent number: 10783910
    Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.
    Type: Grant
    Filed: September 16, 2019
    Date of Patent: September 22, 2020
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Kenneth Haapala, Jon D. Trantham
  • Publication number: 20200251132
    Abstract: A read channel is configured to obtain an analog readback waveform from a magnetic recording medium of a disk drive at a sampling rate of one sample per one written bit. A buffer is coupled the read channel. Circuitry is configured to inject a plurality of different phase offsets into the read channel for each of a plurality of revolutions of the medium. The circuitry is also configured to store, in a buffer, an amplitude of the readback waveform for each of the different phase offsets. The circuitry is further configured to generate an oversampled readback waveform using the amplitudes stored in the buffer.
    Type: Application
    Filed: April 21, 2020
    Publication date: August 6, 2020
    Inventors: Drew Michael Mader, Wenzhong Zhu
  • Patent number: 10684778
    Abstract: Various embodiments of the present invention are generally directed to an apparatus and associated method for updating data in a non-volatile memory array. In accordance with some embodiments, a memory block is formed with a plurality of types of memory cell sectors arranged in data pages of a first type and log pages of a second type that can be updated in-place. A first updated sector is written to a first log page while maintaining an outdated sector in an original data page, and overwritten with a second updated sector.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: June 16, 2020
    Assignee: Seagate Technology LLC
    Inventors: Yiran Chen, Hai Li, Wenzhong Zhu, Xiaobin Wang, Yuan Yan, Harry Hongyue Liu
  • Patent number: 10665254
    Abstract: A read channel is configured to obtain an analog readback waveform from a magnetic recording medium of a disk drive at a sampling rate of one sample per one written bit. A buffer is coupled the read channel. Circuitry is configured to inject a plurality of different phase offsets into the read channel for each of a plurality of revolutions of the medium. The circuitry is also configured to store, in a buffer, an amplitude of the readback waveform for each of the different phase offsets. The circuitry is further configured to generate an oversampled readback waveform using the amplitudes stored in the buffer.
    Type: Grant
    Filed: May 15, 2019
    Date of Patent: May 26, 2020
    Assignee: Seagate Technology LLC
    Inventors: Drew Michael Mader, Wenzhong Zhu
  • Publication number: 20200013430
    Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.
    Type: Application
    Filed: September 16, 2019
    Publication date: January 9, 2020
    Inventors: Wenzhong Zhu, Kenneth Haapala, Jon D. Trantham
  • Patent number: 10431246
    Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.
    Type: Grant
    Filed: December 15, 2016
    Date of Patent: October 1, 2019
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Kenneth Haapala, Jon D. Trantham
  • Patent number: 10366719
    Abstract: A clearance heater of a write head is engaged with a boosted current that exceeds a steady-state current. The steady-state current causes the write head to maintain a desired clearance over a disk during writing, the boosted current being applied before a start of the writing. The boosted current is monotonically decreased before the start of the writing and the steady-state current is applied to the heater after the start of the writing.
    Type: Grant
    Filed: March 20, 2018
    Date of Patent: July 30, 2019
    Assignee: Seagate Technology LLC
    Inventors: Jason W. Riddering, Dustin Mark Cvancara, Kenneth A. Haapala, Eric John McCalla, Wenzhong Zhu, Bin Huang
  • Patent number: 10210891
    Abstract: A storage device includes a storage medium and a transducer head with two writers positioned to write to a same surface of the storage medium. The two writers are separated from one another along a down-track direction of a data track on the storage medium and independently controllable to write data.
    Type: Grant
    Filed: January 20, 2017
    Date of Patent: February 19, 2019
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wei Tian, Jianhua Xue, Wenzhong Zhu, Ralph W. Cross, Javier Guzman
  • Patent number: 10090016
    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: August 3, 2017
    Date of Patent: October 2, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Kaizhong Gao, Wenzhong Zhu, Tim Rausch, Edward Gage
  • Patent number: 10049698
    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: Grant
    Filed: March 31, 2017
    Date of Patent: August 14, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kaizhong Gao, Tim Rausch, Edward Charles Gage
  • Patent number: 10026443
    Abstract: An error is determined in a target track of a heat-assisted recording medium. The error triggers an error recovery procedure. The error recovery procedure involves storing data from at least part of an adjacent track that is immediately proximate the target track to another data storage location. The error recovery procedure also involves, for two or more iterations in which a laser power is incrementally changed from a lower power to a higher power, erasing at least part of the adjacent track at the laser power and attempting to recover the target track.
    Type: Grant
    Filed: May 22, 2017
    Date of Patent: July 17, 2018
    Assignee: Seagate Technology LLC
    Inventors: Wenzhong Zhu, Jason Charles Jury, Pu-Ling Lu, Edward Charles Gage
  • Patent number: 10014020
    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: May 10, 2017
    Date of Patent: July 3, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kenneth A. Haapala, Bin Huang
  • Patent number: 10008231
    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: Grant
    Filed: October 26, 2017
    Date of Patent: June 26, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Steven Granz, Edward Gage, Alfredo Chu, Wenzhong Zhu
  • Publication number: 20180174613
    Abstract: A recording surface of a magnetic disk is divided into first and second zones. A first head of a first actuator arm assembly reads from and/or writes to the first zone exclusively. A second head of a second actuator arm assembly reads from and/or writes to the second zone exclusively. The first and second head are capable of simultaneously reading from and writing to the recording surface.
    Type: Application
    Filed: December 15, 2016
    Publication date: June 21, 2018
    Inventors: Wenzhong Zhu, Kenneth Haapala, Jon D. Trantham
  • Patent number: 9997176
    Abstract: A recording medium is written to using an energy source that heats the medium during the writing. A read error in a sector is determined when reading via a read transducer. While traversing a part of the recording medium that includes data, a write coil is activated before attempting to re-read the sector. The energy source does not heat the recording medium sufficiently to change a state of the data during the activation of the write coil. The activation of the write coil removes a magnetic instability of the read transducer.
    Type: Grant
    Filed: October 24, 2017
    Date of Patent: June 12, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Jason C. Jury, Alfredo Sam Chu
  • 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
  • Patent number: 9916850
    Abstract: A preamplifier circuit can include a control line dedicated to receive a control signal that corresponds to indicating a specific register of the preamplifier circuit, which can allow the preamplifier to switch between utilizing two or more registers to control a current output of the preamplifier circuit. The preamplifier circuit may also have a serial input to program multiple registers of the preamplifier circuit in a serial fashion. In some embodiments, the current output may be a laser bias current. The preamplifier may adjust an output current that drives a laser emitter based on a control signal indicating which specific registers controls the output current. Further, a controller, such as a system-on-chip controller, may selectively vary the control signal to affect the current output of the preamplifier circuit. These systems and methods may be particularly useful for lasers and heat-assisted magnetic recording (HAMR).
    Type: Grant
    Filed: December 12, 2016
    Date of Patent: March 13, 2018
    Assignee: Seagate Technology LLC
    Inventors: Alfredo Sam Chu, Robert Matousek, Todd Michael Lammers, Thomas Lee Schick, Wenzhong Zhu
  • Publication number: 20180047422
    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: October 26, 2017
    Publication date: February 15, 2018
    Inventors: Steven Granz, Edward Gage, Alfredo Chu, Wenzhong Zhu
  • Patent number: 9858961
    Abstract: A storage device includes a multi-reader transducer head with a first reader and a second reader having an effective cross-track separation equal to a multiple of a defined track-pitch of a storage medium of the storage device. The effective cross-track separation may permit for a simultaneous data read of two non-adjacent data tracks.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: January 2, 2018
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Wenzhong Zhu, Kenneth A. Haapala, Kaizhong Gao, Edward Gage