Patents by Inventor Edmun ChianSong Seng
Edmun ChianSong Seng 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: 8120868Abstract: A storage medium format is provided having a first band of a plurality of consecutive data storage tracks having user data stored thereto, a second band of a plurality of consecutive data storage tracks having other user data stored thereto, and a guard track medially disposed therebetween the first band and the second band and having system data stored thereto.Type: GrantFiled: July 28, 2008Date of Patent: February 21, 2012Assignee: Seagate Technology LLCInventors: Qiang Bi, KianKeong Ooi, TaiVie Chiang, WingKong Chiang, Edmun ChianSong Seng, Jimmy Pang, BengWee Quak, UttHeng Kan, Xiong Liu, Ricardo SoonLian Lim, Patrick TaiHeng, MingZhong Dong, WeiMing Yeow
-
Patent number: 8018671Abstract: 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: GrantFiled: May 31, 2007Date of Patent: September 13, 2011Assignee: Seagate Technology LLCInventors: Stephen KowChiew Kuan, AikChuan Lim, Edmun ChianSong Seng, UttHeng Kan, Det Hua Wu
-
Patent number: 7817364Abstract: 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: GrantFiled: April 18, 2006Date of Patent: October 19, 2010Assignee: Seagate Technology LLCInventors: Edmun ChianSong Seng, AikChuan Lim, Stephen KowChiew Kuan, UttHeng Kan, Lin Nah Lim, Det Hau Wu
-
Publication number: 20100007986Abstract: A storage medium having a boundary located along a surface of the storage medium that functions as a transition point for selectively operating a first writer and a second writer of a plurality of writers, where the location of the boundary is set based on writing capabilities of the plurality of writers.Type: ApplicationFiled: July 14, 2008Publication date: January 14, 2010Applicant: Seagate Technology, LLCInventors: HonYeong Mak, Lin Nah Lim, Det Hau Wu, Edmun ChianSong Seng, UttHeng Kan
-
Patent number: 7561357Abstract: A multistage decoder circuit has an error reduction stage that includes an adaptation circuit. The adaptation circuit provides adaptable error reduction as a function of bit error rate. The multistage decoder circuit has an energization control circuit that couples to the adaptation circuit. The energization control circuit controls an energization of the adaptation circuit as a function of actual or expected channel quality.Type: GrantFiled: August 11, 2005Date of Patent: July 14, 2009Assignee: Seagate Technology LLCInventors: Det Hau Wu, Edmun ChianSong Seng, Lin Nah Lim, UttHeng Kan
-
Patent number: 7536625Abstract: A method of recovering data on a storage medium is provided. A first error correction scheme is performed on a high risk region of the storage medium. A second error correction scheme is performed on a remaining portion of the storage medium.Type: GrantFiled: December 22, 2006Date of Patent: May 19, 2009Assignee: Seagate Technology LLCInventors: Edmun ChianSong Seng, UttHeng Kan, AC Lim, Det Hau Wu, Lin Nah Lim, Stanton M. Keeler, Curtis M. Pleiss
-
Patent number: 7508617Abstract: Apparatus and methods are disclosed that regulate head fly height so as to compensate for variation in height of a disk surface. An exemplary apparatus includes a circuit that detects disk height variation in response to variation in the gain of a variable gain amplifier, within an automatic gain control loop, that amplifies a read signal as the head reads from the disk surface. The circuit regulates the head fly height so as to compensate for the detected variation in disk height.Type: GrantFiled: September 7, 2007Date of Patent: March 24, 2009Assignee: Seagate Technology LLCInventors: HonYeong Mak, LinNah Lim, DetHau Wu, Edmun ChianSong Seng, UttHeng Kan
-
Publication number: 20090067095Abstract: Apparatus and methods are disclosed that regulate head fly height so as to compensate for variation in height of a disk surface. An exemplary apparatus includes a circuit that detects disk height variation in response to variation in the gain of a variable gain amplifier, within an automatic gain control loop, that amplifies a read signal as the head reads from the disk surface. The circuit regulates the head fly height so as to compensate for the detected variation in disk height.Type: ApplicationFiled: September 7, 2007Publication date: March 12, 2009Inventors: HonYeong Mak, LinNah Lim, DetHau Wu, Edmun ChianSong Seng, UttHeng Kan
-
Publication number: 20080304172Abstract: A storage medium format is provided having a first band of a plurality of consecutive data storage tracks having user data stored thereto, a second band of a plurality of consecutive data storage tracks having other user data stored thereto, and a guard track medially disposed therebetween the first band and the second band and having system data stored thereto.Type: ApplicationFiled: July 28, 2008Publication date: December 11, 2008Applicant: SEAGATE TECHNOLOGY LLCInventors: Qiang Bi, KianKeong Ooi, TaiVie Chiang, WingKong Chiang, Edmun ChianSong Seng, Jimmy Pang, BengWee Quak, UttHeng Kan, Xiong Liu, Ricardo SoonLian Lim, Patrick TaiHeng Wong, MingZhong Ding, WeiMing Yeow
-
Publication number: 20080298196Abstract: 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: ApplicationFiled: May 31, 2007Publication date: December 4, 2008Applicant: SEAGATE TECHNOLOGY LLCInventors: Stephen KowChiew Kuan, AikChuan Lim, Edmun ChianSong Seng, UttHeng Kan, Det Hua Wu
-
Patent number: 7417813Abstract: 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: GrantFiled: May 26, 2004Date of Patent: August 26, 2008Assignee: Seagate Technology LLCInventors: AikChuan Lim, Edmun ChianSong Seng, Xiong Liu, UttHeng Kan
-
Patent number: 7405893Abstract: A data storage medium and data storage system with improved efficiency of formatting are provided. One illustrative embodiment of the present invention pertains to a data storage medium. The data storage medium includes a first zone having servo information written with a first frequency, a second zone having servo information written with a second frequency, and a guard band disposed between the first zone and the second zone. The use of different frequencies in different zones contributes to optimizing the properties of the data storage medium, and the guard band contributes to optimizing the usage of the different zones.Type: GrantFiled: September 21, 2005Date of Patent: July 29, 2008Assignee: Seagate Technology LLCInventors: Qiang Bi, KianKeong Ooi, TaiVie Chiang, WingKong Chiang, Edmun ChianSong Seng, Jimmy Pang, BengWee Quak, UttHeng Kan, Xiong Liu, Ricardo SoonLian Lim, Patrick TaiHeng Wong, MingZhong Ding, WeiMing Yeow
-
Patent number: 7392439Abstract: A computer process establishes data frequencies for recording data in zones of a zone bit recording medium in a disc drive. At least three data points are identified for each zone correlating data frequencies and corresponding bit error rates, and a slope of a curve between each two data points is calculated. The slopes are averaged, and the data frequency is calculated based on the average slope. If a difference between the average and default slopes exceeds a first threshold value, or if a spread of the slopes exceeds a second threshold value, the data frequency is calculated based on the average slope and the default slope. In one embodiment, each of the three data points is generated by recording data in the zone at each of three selected data frequencies, reading the recorded data, and calculating bit error rates based on the recorded and read data.Type: GrantFiled: May 9, 2003Date of Patent: June 24, 2008Assignee: Seagate Technology LLCInventors: Edmun ChianSong Seng, DetHau Wu, UttHeng Kan, LinNah Lim
-
Patent number: 6981197Abstract: An enhanced interleave type error correction method is provided in which decoding of an enhanced interleave block is done. Subsequently the decoding may be done by decoding the estimated codewords multiple times using a single error correction code. In addition, a decoder and a digital communication system for implementing the enhanced interleave type error correction method are provided.Type: GrantFiled: January 23, 2002Date of Patent: December 27, 2005Assignee: Seagate Technology LLCInventors: Bin Liu, Edmun ChianSong Seng, UttHeng Kan
-
Patent number: 6940671Abstract: 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: GrantFiled: September 26, 2001Date of Patent: September 6, 2005Assignee: Seagate Technology LLCInventors: Edmun ChianSong Seng, AikChuan Lim, Kay Hee Tang, UttHeng Kan, Jeffrey Soon Beng Sim
-
Patent number: 6862152Abstract: A channel adjustment control adjusts a channel to reduce bit error rate in a disc drive. Variable gain register settings are read and compared to filter characteristics to provide an operational boost register setting for an adjustable gain amplifier in the channel. An operational pole register setting is provided based on the operational boost register setting and known parameters of the adjustable low pass filter. Low and high frequency data patterns are applied while the channel adjustment control reads the variable gain register settings.Type: GrantFiled: February 25, 2003Date of Patent: March 1, 2005Assignee: Seagate Technology LLCInventors: DetHau Wu, Edmun ChianSong Seng, Utt Heng Kan
-
Publication number: 20040225933Abstract: A computer process establishes data frequencies for recording data in zones of a zone bit recording medium in a disc drive. At least three data points are identified for each zone correlating data frequencies and corresponding bit error rates, and a slope of a curve between each two data points is calculated. The slopes are averaged, and the data frequency is calculated based on the average slope. If a difference between the average and default slopes exceeds a first threshold value, or if a spread of the slopes exceeds a second threshold value, the data frequency is calculated based on the average slope and the default slope. In one embodiment, each of the three data points is generated by recording data in the zone at each of three selected data frequencies, reading the recorded data, and calculating bit error rates based on the recorded and read data.Type: ApplicationFiled: May 9, 2003Publication date: November 11, 2004Inventors: Edmun ChianSong Seng, DetHau Wu, UttHeng Kan, LinNah Lim
-
Publication number: 20040165303Abstract: A channel adjustment control adjusts a channel to reduce bit error rate in a disc drive. Variable gain register settings are read and compared to filter characteristics to provide an operational boost register setting for an adjustable gain amplifier in the channel. An operational pole register setting is provided based on the operational boost register setting and known parameters of the adjustable low pass filter. Low and high frequency data patterns are applied while the channel adjustment control reads the variable gain register settings.Type: ApplicationFiled: February 25, 2003Publication date: August 26, 2004Inventors: DetHau Wu, Edmun ChianSong Seng, Utt Heng Kan
-
Patent number: 6735029Abstract: A method and apparatus for obtaining optimum parameter values for a read channel employed in a disc drive storage system are provided in which data having a known pattern is written on a disc surface of the disc drive storage system. The data written on the disc surface is then read to obtain a readback signal. The readback signal is passed through the read channel. A readback signal response is obtained at an output test point of the read channel. The readback signal response at the output test point is compared with a target response of the read channel at the output test point. The comparison is carried out using frequency spectral analysis. At least one parameter of the read channel is adjusted if the readback signal response substantially differs from the target response.Type: GrantFiled: October 15, 2001Date of Patent: May 11, 2004Assignee: Seagate Technology LLCInventors: Edmun ChianSong Seng, UttHeng Kan
-
Publication number: 20030174431Abstract: 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: ApplicationFiled: June 25, 2002Publication date: September 18, 2003Applicant: Seagate Technology LLCInventors: Edmun ChianSong Seng, Xiong Liu, AikChuan Lim, UttHeng Kan