Patents by Inventor AikChuan Lim

AikChuan Lim 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: 10720177
    Abstract: A method includes writing first data to a first track of a magnetic recording medium of a storage device. First parity sectors corresponding to the first data are written. The first parity sectors have a first size. Second parity sectors corresponding to the first data are written. The second parity sectors have a second size. Second data is written to a second track of the magnetic recording medium. The second track is adjacent to the first track. It is determined whether an unrecoverable data error has occurred on the second track. After writing to the second track and determining that no unrecoverable data error has occurred, the first and second parity sectors corresponding to the first data are released.
    Type: Grant
    Filed: April 8, 2019
    Date of Patent: July 21, 2020
    Assignee: Seagate Technology LLC
    Inventors: ChoonWei Ng, Wei Zhang, Harry Tiotantra, Utt Heng Kan, AikChuan Lim
  • Patent number: 8018671
    Abstract: A method to map defects is provided. A select data track of a storage medium is scanned for a defect. At least one data wedge affected by the defect on the select data track is identified. Each data wedge includes available area for writing user data defined between two servo wedges that include position information. The at least one affected data wedge is identified as unusuable.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: September 13, 2011
    Assignee: Seagate Technology LLC
    Inventors: Stephen KowChiew Kuan, AikChuan Lim, Edmun ChianSong Seng, UttHeng Kan, Det Hua Wu
  • Patent number: 7817364
    Abstract: A method is provided. The method includes determining that a data sector included in a select data track is in error, the data sector in error includes at least one identified data wedge. The at least one defective data wedge in the data sector in error is located. The method also includes moving the at least one defective data wedge by utilizing at least one spare wedge on the select data track.
    Type: Grant
    Filed: April 18, 2006
    Date of Patent: October 19, 2010
    Assignee: Seagate Technology LLC
    Inventors: Edmun ChianSong Seng, AikChuan Lim, Stephen KowChiew Kuan, UttHeng Kan, Lin Nah Lim, Det Hau Wu
  • Publication number: 20080298196
    Abstract: A method to map defects is provided. A select data track of a storage medium is scanned for a defect. At least one data wedge affected by the defect on the select data track is identified. Each data wedge includes available area for writing user data defined between two servo wedges that include position information. The at least one affected data wedge is identified as unusuable.
    Type: Application
    Filed: May 31, 2007
    Publication date: December 4, 2008
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Stephen KowChiew Kuan, AikChuan Lim, Edmun ChianSong Seng, UttHeng Kan, Det Hua Wu
  • Patent number: 7417813
    Abstract: A data recording apparatus includes a surface having a plurality of data tracks with leading track portions. A head moves along head paths over the data tracks to provide data access. The data access has a reduced reliability along a limited number of the leading track portions. Trailing path additions follow the head paths for the limited number of leading track portions. The trailing path additions providing overlapping data access for the limited number of leading track portions.
    Type: Grant
    Filed: May 26, 2004
    Date of Patent: August 26, 2008
    Assignee: Seagate Technology LLC
    Inventors: AikChuan Lim, Edmun ChianSong Seng, Xiong Liu, UttHeng Kan
  • Publication number: 20070242379
    Abstract: A method is provided. The method includes determining that a data sector included in a select data track is in error, the data sector in error includes at least one identified data wedge. The at least one defective data wedge in the data sector in error is located. The method also includes moving the at least one defective data wedge by utilizing at least one spare wedge on the select data track.
    Type: Application
    Filed: April 18, 2006
    Publication date: October 18, 2007
    Applicant: Seagate Technology LLC
    Inventors: Edmun Seng, AikChuan Lim, Stephen Kuan, UttHeng Kan, Lin Lim, Det Wu
  • Publication number: 20050275962
    Abstract: A data recording apparatus includes a surface having a plurality of data tracks with leading track portions. A head moves along head paths over the data tracks to provide data access. The data access has a reduced reliability along a limited number of the leading track portions. Trailing path additions follow the head paths for the limited number of leading track portions. The trailing path additions providing overlapping data access for the limited number of leading track portions.
    Type: Application
    Filed: May 26, 2004
    Publication date: December 15, 2005
    Inventors: AikChuan Lim, Edmun Seng, Xiong Liu, UttHeng Kan
  • Patent number: 6940671
    Abstract: Systems and methods are provided through which a time domain equalized signal-to-noise-ratio (ESNR) of an electronic device is determined by executing ESNR determining firmware in the electronic device. The ESNR is used to perform rejection/acceptance testing of the electronic device during manufacturing of the device, and/or to perform read channel tuning and optimization. In one embodiment, determination of the ESNR includes both phase level retry and global level retry.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: September 6, 2005
    Assignee: Seagate Technology LLC
    Inventors: Edmun ChianSong Seng, AikChuan Lim, Kay Hee Tang, UttHeng Kan, Jeffrey Soon Beng Sim
  • Patent number: 6853511
    Abstract: A number of data pairs, each data pair comprises a write-to-read track misregistration (WRTMR) value and an average position error margin (APE) value, are determined for a data storage device. Each of the data pairs is associated with a unique predetermined non-repeatable runout (NRRO) error in the data storage device. Each of the predetermined NRRO errors is caused by subjecting the data storage device to a unique NRRO error stimulus. An ideal APE margin is then determined for the data storage device by using the data pairs to extrapolate an APE margin corresponding to a WRTMR value of zero.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: February 8, 2005
    Assignee: Seagate Technology LLC
    Inventors: Edmund ChianSong Seng, Xiong Liu, AikChuan Lim, UttHeng Kan
  • Publication number: 20030174431
    Abstract: A number of data pairs, each data pair comprises a write-to-read track misregistration (WRTMR) value and an average position error margin (APE) value, are determined for a data storage device. Each of the data pairs is associated with a unique predetermined non-repeatable runout (NRRO) error in the data storage device. Each of the predetermined NRRO errors is caused by subjecting the data storage device to a unique NRRO error stimulus. An ideal APE margin is then determined for the data storage device by using the data pairs to extrapolate an APE margin corresponding to a WRTMR value of zero.
    Type: Application
    Filed: June 25, 2002
    Publication date: September 18, 2003
    Applicant: Seagate Technology LLC
    Inventors: Edmun ChianSong Seng, Xiong Liu, AikChuan Lim, UttHeng Kan
  • Patent number: 6583942
    Abstract: A method and data storage device determine an equalized signal-to-noise ratio in the storage device. The equalized signal-to-noise ratio is determined by generating an analog read signal, passing the read signal through an equalizer in the storage device, and sampling the equalized signal using an analog-to-digital converter in the storage device. The samples from the analog-to-digital converter are then used in the equalized signal-to-noise calculation.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: June 24, 2003
    Assignee: Seagate Technology LLC
    Inventors: Edmun ChianSong Seng, UttHeng Kan, AikChuan Lim, KayHee Tang
  • Publication number: 20020128787
    Abstract: Systems and methods are provided through which a time domain equalized signal-to-noise-ratio (ESNR) of an electronic device is determined by executing ESNR determining firmware in the electronic device. The ESNR is used to perform rejection/acceptance testing of the electronic device during manufacturing of the device, and/or to perform read channel tuning and optimization. In one embodiment, determination of the ESNR includes both phase level retry and global level retry.
    Type: Application
    Filed: September 26, 2001
    Publication date: September 12, 2002
    Inventors: Edmun ChianSong Seng, AikChuan Lim, Kay Hee Tang, UttHeng Kan, Jeffrey Soon Beng Sim
  • Publication number: 20020075585
    Abstract: An information handling system, such as a magnetic disc drive, includes a method and apparatus for performing an onboard microtrack profile test for characterizing the head sensitivity of a magneto-resistive head. The method comprises formation of a very narrow written signal on a track and execution of a microtrack scan based on the count feature from the variable gain amplifier (VGA) from the read channel.
    Type: Application
    Filed: September 27, 2001
    Publication date: June 20, 2002
    Inventors: Peter Tri Luong, AikChuan Lim, Edmun ChianSong Seng, UttHeng Kan
  • Publication number: 20020054443
    Abstract: A method and data storage device determine an equalized signal-to-noise ratio in the storage device. The equalized signal-to-noise ratio is determined by generating an analog read signal, passing the read signal through an equalizer in the storage device, and sampling the equalized signal using an analog-to-digital converter in the storage device. The samples from the analog-to-digital converter are then used in the equalized signal-to-noise calculation.
    Type: Application
    Filed: September 26, 2001
    Publication date: May 9, 2002
    Inventors: Edmun ChianSong Seng, UttHeng Kan, Aikchuan Lim, KeyHee Tang