Patents by Inventor Kathy X. Tang

Kathy X. Tang 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: 9368131
    Abstract: A data storage device is disclosed wherein when a first head is over a top disk surface, a first undershoot of a first cross-track profile is closer to an inner diameter of a disk and a second undershoot of the first cross-track profile is closer to an outer diameter of the disk. When a second head is over a bottom disk surface, a second undershoot of a second cross-track profile is closer to the inner diameter of the disk and a first undershoot of the second cross-track profile is closer to the outer diameter of the disk.
    Type: Grant
    Filed: April 3, 2015
    Date of Patent: June 14, 2016
    Assignee: Western Digital (Fremont), LLC
    Inventors: Kathy X. Tang, Xiao Z. Wu, Hong Pan
  • Patent number: 9117463
    Abstract: A data storage device is disclosed comprising a disk comprising a plurality of data tracks, and a head actuated over the disk. A retry operation for a target data track is performed by positioning the head at a first radial location and first erasing at least part of a first data track adjacent the target data track. After the first erasing, the target data track is first read to first recover target data recorded in the target data track. When the first recovery fails, the head is positioned at a second radial location and more of the first data track is second erased. After the second erasing, the target data track is second read to second recover the target data recorded in the target data track.
    Type: Grant
    Filed: June 23, 2014
    Date of Patent: August 25, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Kathy X. Tang, Jerry G. Le
  • Patent number: 9093095
    Abstract: An apparatus includes: a media; a head over the media; and control circuitry configured to cause the head to: write a first precondition track with a preconditioning pattern on the media, and write a data track on the media at a first inter-track spacing with the head positioned in a first direction from the first precondition track.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: July 28, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Donald Brunnett, Kathy X. Tang, Jerry G. Le
  • Patent number: 9082458
    Abstract: A data storage device is disclosed comprising a plurality of disk surfaces, and a head actuated over each disk surface. For each disk surface, a quality metric is measured at a plurality of discrete areal densities including a first areal density comprising a first radial density and a first linear density, and a second areal density comprising a second radial density different from the first radial density and a second linear density different from the first linear density. Based on a target capacity, an areal density is selected for each disk surface such that the combined areal densities satisfies the target capacity and such that the quality metrics across the disk surfaces are substantially equal and substantially maximized.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: July 14, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventor: Kathy X. Tang
  • Patent number: 9076474
    Abstract: A data storage device is disclosed comprising a head actuated over a disk. A first spacing pattern is written to the disk and a second spacing pattern is written to the disk different from the first spacing pattern. A first fly height measurement (FHM1_1) is generated by reading the first spacing pattern and a first fly height measurement (FHM2_1) is generated by reading the second spacing pattern. After an interval, a second fly height measurement (FHM1_2) is generated by reading the first spacing pattern and a second fly height measurement (FHM2_2) is generated by reading the second spacing pattern. A change in the fly height of the head is estimated based on: (?FHM2?B·?FHM1)/(A?B) where ?FHM1 represents a difference between FHM1_1 and FHM1_2, ?FHM2 represents a difference between FHM2_1 and FHM2_2, and A and B are constants.
    Type: Grant
    Filed: December 23, 2014
    Date of Patent: July 7, 2015
    Assignee: Western Digital Technologies, Inc.
    Inventors: Kathy X. Tang, Jerry G. Le
  • Publication number: 20150109701
    Abstract: An apparatus includes: a media; a head over the media; and control circuitry configured to cause the head to: write a first precondition track with a preconditioning pattern on the media, and write a data track on the media at a first inter-track spacing with the head positioned in a first direction from the first precondition track.
    Type: Application
    Filed: December 20, 2013
    Publication date: April 23, 2015
    Applicant: Western Digital Technologies, Inc.
    Inventors: DONALD BRUNNETT, KATHY X. TANG, JERRY G. LE
  • Patent number: 8094401
    Abstract: A method of detecting skip track erasure for a head and disk of a disk drive is disclosed. N tracks are DC erased, and a periodic pattern is written to the disk at a target track within the DC erased tracks. The periodic pattern is substantially comprised of a high frequency component greater than 450 MHz. After writing the periodic pattern to the target track at least twice, at least two of the DC erased tracks other than the target track are read to generate respective read signals. The read signals are processed to detect a skip track erasure event.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: January 10, 2012
    Assignee: Western Digital Technologies, Inc.
    Inventors: Qingzhi Peng, Kathy X. Tang
  • Patent number: 7099117
    Abstract: A head stack assembly includes a flex cable assembly. The head stack assembly further includes an actuator arm and a load beam coupled to the actuator arm. The head stack assembly further includes a trace suspension assembly backing layer coupled to the load beam and including a gimbal. The head stack assembly further includes a dielectric layer disposed upon the trace suspension assembly backing layer. The head stack assembly further includes a slider supported by the gimbal. The head stack assembly further includes a ground trace disposed upon the dielectric layer with the dielectric layer between the ground trace and the trace suspension assembly backing layer. The ground trace extends along the actuator arm and is electrically connected to the slider and the flex cable assembly for grounding the slider to the flex cable assembly.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: August 29, 2006
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jai N. Subrahmanyam, Gopalakrishna Kote, Kathy X. Tang, Loi D. Pham, Jack M. Chue
  • Patent number: 7027264
    Abstract: According to an aspect of the present invention, there is provided a slider for a disk drive. The slider includes a slider body including a slider body outer surface. The slider further includes an inductive write head including main and return poles. The slider further includes a slider ground pad disposed at the slider body outer surface. The slider ground pad is disposed in electrical communication with the main and return poles for electrically grounding the main and return poles.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: April 11, 2006
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jai N. Subrahmanyam, Gopalakrishna Kote, Kathy X. Tang, Loi D Pham, Jack M. Chue
  • Patent number: 6972930
    Abstract: A Head Gimbal Assembly (HGA) for use in a disk drive and comprising an ESD-protected slider comprising a head formed on a slider substrate. The slider may comprise an electrical-isolation circuit; an electrically-resistive path between head input connections and the slider; or both isolation circuits and resistive paths for reducing electrostatic charge on the slider while remaining connected during disk drive operations.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: December 6, 2005
    Assignee: Western Digital Technologies, Inc.
    Inventors: Kathy X. Tang, Jai N. Subrahmanyam, Rahmat Karimi
  • Patent number: 6891702
    Abstract: A disk drive includes a disk having a recording surface, a head stack assembly that includes a body portion, an actuator arm cantilevered from the body portion and a head gimbal assembly supported at the actuator arm. The head gimbal assembly includes a suspension having a first end and a second end, the first end being attached to the actuator arm, a slider coupled to the second end of the suspension, the slider comprising a transducer for reading from and writing to the recording surface. A gimbal is coupled to the second end of the suspension and to the slider. An array of diodes is attached to the suspension to protect the transducer from electrostatic discharge or electrical overstress events.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: May 10, 2005
    Assignee: Western Digital Technologies, Inc.
    Inventor: Kathy X. Tang