Patents by Inventor Myint Ngwe

Myint Ngwe 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: 7065605
    Abstract: According to one embodiment of the present invention, a method of tuning a Power-On-Reset (POR) register in a data storage device comprises determining a tuned value for the POR register using feedback from the data storage device obtained during a certification process of the data storage device and storing a list in one or more system sectors of the data storage device, the list comprising an address of the POR register to be patched and the tuned value. According to another embodiment of the present invention, a disc drive comprises a rotatable disc, a microprocessor, and a memory. The memory has a start-up routine that, when executed by the microprocessor, causes the microprocessor to patch a Power-On-Reset (POR) register using a tuned values stored in one or more system sectors of the rotatable disc.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: June 20, 2006
    Assignee: Seagate Technology LLC
    Inventors: WeiMing Yeow, QuekLeong Choo, Myint Ngwe, FongKheon Chong, KianWai Ng
  • Publication number: 20050270679
    Abstract: A motion control system has an enclosed assembly that encloses moving parts. A controller controls a motion of the moving parts and has an inhibit input that inhibits the motion. A sensor provides sensor outputs that depend on an assembly temperature and an assembly humidity in the enclosed assembly. A circuit provides a condensing condition output as a function of the sensor outputs. The condensing condition output couples to the inhibit input to inhibit the motion as a function of the sensor outputs.
    Type: Application
    Filed: June 2, 2004
    Publication date: December 8, 2005
    Inventors: Chew Victor, David Loh, Gan Liang, Djohni Chandra, Myint Ngwe
  • Patent number: 6952321
    Abstract: A method of determining run-out in a disc drive involving steps of performing a direct current erase, selecting a reference track, writing a sinusoidal signal into a first track at a first offset from the reference track, sensing a read signal along the reference track, and analyzing the read signal to extract run-out information.
    Type: Grant
    Filed: April 10, 2002
    Date of Patent: October 4, 2005
    Assignee: Seagate Technology LLC
    Inventors: EngHock Lim, BengTheam Ko, Jun Wang, MingYou Hu, Myint Ngwe
  • Patent number: 6947232
    Abstract: Method and apparatus for detecting defects in a magnetic medium of a data handling system. The magnetic medium includes a number of user data wedges each disposed between an adjacent pair of servo data wedges. A predetermined data sequence is written to the user data wedges, and subsequently read to generate a readback signal. A sequence of discrete time sample values are generated from the readback signal. Defects in the medium are detected in relation to the magnitudes of the discrete time samples. A media scan controller outputs a first multi-bit information record having at least one bit composing the address of the user data wedge containing a defect, and a second multi-bit information record having at least one bit composing an address of the defect within the user data wedge. No information is written to the buffer when no defects are identified.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: September 20, 2005
    Assignee: Seagate Technology LLC
    Inventors: TeckKhoon Lim, Myint Ngwe, KokHoe Chia
  • Patent number: 6920001
    Abstract: A method of categorizing magnitudes of thermal asperities in a read-back signal of a data storage system includes receiving the read-back signal from a location containing a thermal asperity. A peak magnitude signal is generated from the read-back signal. A threshold signal is generated using a variable threshold generator. The peak magnitude signal is compared to the threshold signal and a magnitude of the thermal asperity is categorized as a function of the comparison.
    Type: Grant
    Filed: June 12, 2003
    Date of Patent: July 19, 2005
    Assignee: Seagate Technology LLC
    Inventors: Teng Hou Sebastian Chua, Myint Ngwe, Lan Xia, Beng Wee Quak, Quek Leong Choo
  • Patent number: 6903889
    Abstract: A method of tuning a bias parameter for a magnetoresistive head in a data storage system includes the step of identifying, from multiple possible bias parameter values, a smallest bias parameter value for the magnetoresistive head which both maintains a bit error rate above a predetermined threshold bit error rate, and which satisfies a second criteria. The method then includes the step of setting an operational bias parameter value for the magnetoresistive head to the identified smallest bias parameter value. Also disclosed are data storage systems, or controllers which are connectable to or included with data storage systems, configured to implement the methods.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: June 7, 2005
    Assignee: Seagate Technology
    Inventors: Liu Li, Quek Leong Choo, Song Wee Teo, Myint Ngwe, Beng Wee Quak
  • Publication number: 20050066227
    Abstract: A buffer random access memory has a first portion reserved for a defect table and a second portion reserved for data caching. A method of managing the buffer random access memory includes determining actual memory space of the first portion which is occupied by the defect table. This identifies unused memory space of the first portion of the buffer random access memory. The method then includes reallocating the unused memory space of the first portion of the buffer random access memory for use in data caching. Controllers and mass storage devices which implement the method are also provided.
    Type: Application
    Filed: September 18, 2003
    Publication date: March 24, 2005
    Inventors: KokHoe Chia, Myint Ngwe, JinQuan Shen, SweeKieong Choo
  • Publication number: 20050028023
    Abstract: According to one embodiment of the present invention, a method of tuning a Power-On-Reset (POR) register in a data storage device comprises determining a tuned value for the POR register using feedback from the data storage device obtained during a certification process of the data storage device and storing a list in one or more system sectors of the data storage device, the list comprising an address of the POR register to be patched and the tuned value. According to another embodiment of the present invention, a disc drive comprises a rotatable disc, a microprocessor, and a memory. The memory has a start-up routine that, when executed by the microprocessor, causes the microprocessor to patch a Power-On-Reset (POR) register using a tuned values stored in one or more system sectors of the rotatable disc.
    Type: Application
    Filed: July 28, 2003
    Publication date: February 3, 2005
    Inventors: WeiMing Yeow, QuekLeong Choo, Myint Ngwe, FongKheon Chong, KianWai Ng
  • Patent number: 6839193
    Abstract: A method for optimizing the read-to-write offset of a disk drive system in respect of a track is provided. In one aspect the method includes the step of determining a first read position amongst a range of test positions offset relative to the track on the basis of read signal strength. The method further includes the steps of calculating a subrange of test positions about the first read position, selecting a second read position from the subrange on the basis of bit error rates and setting the read-to-write offset as a function of the second read position. In addition a disk drive system including means for optimally setting the read-to-write offset in respect of a track is provided.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: January 4, 2005
    Assignee: Seagate Technology LLC
    Inventors: Fong Kheon Chong, Quek Leong Choo, Myint Ngwe, Jun Wang, Kah Liang Gan
  • Publication number: 20040252392
    Abstract: A method of categorizing magnitudes of thermal asperities in a read-back signal of a data storage system includes receiving the read-back signal from a location containing a thermal asperity. A peak magnitude signal is generated from the read-back signal. A threshold signal is generated using a variable threshold generator. The peak magnitude signal is compared to the threshold signal and a magnitude of the thermal asperity is categorized as a function of the comparison.
    Type: Application
    Filed: June 12, 2003
    Publication date: December 16, 2004
    Applicant: Seagate Technology LLC
    Inventors: Teng Hou Sebastian Chua, Myint Ngwe, Lan Xia, Beng Wee Quak, Quek Leong Choo
  • Publication number: 20040252398
    Abstract: A method of tuning a bias parameter for a magnetoresistive head in a data storage system includes the step of identifying, from multiple possible bias parameter values, a smallest bias parameter value for the magnetoresistive head which both maintains a bit error rate above a predetermined threshold bit error rate, and which satisfies a second criteria. The method then includes the step of setting an operational bias parameter value for the magnetoresistive head to the identified smallest bias parameter value. Also disclosed are data storage systems, or controllers which are connectable to or included with data storage systems, configured to implement the methods.
    Type: Application
    Filed: June 11, 2003
    Publication date: December 16, 2004
    Applicant: Seagate Technology LLC
    Inventors: Liu Li, Quek Leong Choo, Song Wee Teo, Myint Ngwe, Beng Wee Quak
  • Patent number: 6822815
    Abstract: A magnetoresistive element measurement circuit configured for measuring resistance of a magnetoresistive element biased by a current source is disclosed. In a preferred embodiment, the measurement circuit includes the magnetoresistive element, a current source providing a fixed current to the magnetoresistive element, at least one current bypass switch controllingly engaging a measurement resistor in an electrical parallel configuration with the biased magnetoresistive element, and an analogue voltage detector measuring voltage first across the biased magnetoresistive element and then across the biased magnetoresistive element in electrical parallel communication with the measurement resistor. The measured voltages are factored with the measurement resistor to determine the resistance of the magnetoresistive element.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: November 23, 2004
    Assignee: Seagate Technology LLC
    Inventors: Eng Hock Lim, Khai Sheng Ng, Fong Kheon Chong, Chew Weng Khin Victor, Myint Ngwe
  • Patent number: 6822814
    Abstract: An apparatus and associated method for detecting head collision with disc media, or other matter, during a write operation is disclosed. The method and apparatus generally monitor the resistance of an MR element on the head in order to detect a temperature increases indicative of a head collision. The resistance can be compared to a pre-selected threshold to generate an output indicative of head collision.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: November 23, 2004
    Assignee: JPMorgan Chase Bank, As Collateral Agent
    Inventors: WeiLoon Ng, Myint Ngwe, QuekLeong Choo, EngHock Lim, KokHoe Chia, CheeWai Lum
  • Patent number: 6798596
    Abstract: A guardband portion is written on a disc surface in a disc drive. A predetermined data pattern is written on at least one data track adjacent to the guardband portion. A predetermined guardband pattern is written at a plurality of different guardband frequencies in the guardband portion. For each guardband frequency, at least one performance criterion is measured for the data track. A desired guardband pattern is written on the guardband portion of the disc surface at a guardband frequency chosen based on the measured performance criterion.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: September 28, 2004
    Assignee: Seagate Technology LLC
    Inventors: Eng Hock Lim, Quek Leong Choo, Kok Leong Loh, Myint Ngwe, Kah Liang Gan
  • Patent number: 6795261
    Abstract: Method and apparatus for increasing process yields of data storage devices which store data on media surfaces using read/write heads. An initial linear bit recording density is determined for each head, the linear bit recording density comprising a density at which each head is capable of writing data to and reading data from the corresponding media surface. Defective storage sectors are identified on the media surfaces to determine whether a sufficient number of logical storage sectors are available to meet a predetermined data storage capacity. The linear bit recording density of at least one of the heads is then altered to ensure that the storage device has sufficient logical storage sectors to meet the predetermined capacity.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: September 21, 2004
    Assignee: Seagate Technology LLC
    Inventors: KokHoe Chia, TeckKhoon Lim, CheeWai Lum, Myint Ngwe, BengWee Quak
  • Patent number: 6765736
    Abstract: A disc drive with on-the-fly verification of an enabled condition of the write element, comprising a rotatable disc having a magnetic recording surface, and a data reading and writing assembly. The data reading and writing assembly comprises a read/write head comprising a write element and a read element, both adjacent the recording surface; a preamplifier comprising a write driver applying a series of write currents for writing data to the recording surface and a read amplifier for reading stored data from the recording surface; and an interconnect joining the write driver to the write element so as to generate time-varying magnetic fields selectively magnetizing the recording surface in response to the write currents, and joining the read amplifier to the read element so as to transduce magnetization vectors on the recording surface associated with stored data.
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: July 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Beng Theam Ko, Eng Hock Lim, Victor WengKhin Chew, Myint Ngwe, Kah Liang Gan
  • Patent number: 6731442
    Abstract: A method is disclosed for detecting defects in a recordable medium such as a hard disc drive based on error energy. The method may include the steps of writing test data to the medium and reading back the test data. The method may also include the steps of computing an error energy based on the square of the difference between the read back data and an ideal version of the test data and comparing the error energy with an energy threshold. The method generates a defect signal when the error energy exceeds the energy threshold. The method may also be used to identify the media defect according to its error energy profile. An apparatus for detecting defects in a recordable medium is also disclosed.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: May 4, 2004
    Assignee: Seagate Technologies LLC
    Inventors: Ming Jin, Myint Ngwe, David Loh, Quek Leong Choo, Mingyou Hu
  • Patent number: 6724562
    Abstract: A method for writing servo patterns on at least one disc in a disc drive that has a first set of tracks and a second set of tracks on a major surface of the disc includes stepping between the tracks of the first set of tracks at a first constant angle, and stepping between the tracks of the second set of tracks at a second constant angle. Stepping between tracks in the first group or the second group includes selecting two adjacent tracks from either the first group of tracks or the second group of tracks, and determining the angle through which an actuator assembly must be rotated between the two adjacent tracks selected to produce a selected track pitch. The method produces a disc for a disc drive with a first set of tracks, and a second set of tracks in which the track pitch varies across the set of tracks.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: April 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Chiap Heok Ang, Niroot Jierapipatanakul, Beng Theam Ko, Myint Ngwe, Beng Wee Quak, Choonkiat Lim
  • Patent number: 6724550
    Abstract: A method for the adaptive dampening of a peak amplitude of a thermal asperity signal in a disc drive to minimize loss of read data integrity, including the steps of determining a peak-to-peak preamble signal amplitude for identifying an amplitude signal range of the peak amplitude of the thermal asperity signal; measuring the peak amplitude of the thermal asperity signal; separating the peak-to-peak preamble signal amplitude into substantially even portions for use in calculating a value of the amplitude signal range of the peak amplitude of the thermal asperity signal; calculating the value of the amplitude signal range of the peak amplitude of the thermal asperity signal for use in determining a dampening resistance used by a dampening circuit to adaptively dampen the peak amplitude of the thermal asperity signal; and activating the dampening circuit to dampen the peak amplitude of the thermal asperity signal.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: April 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Eng Hock Lim, Beng Theam Ko, Hweepeng Teo, Fong Kheon Chong, Myint Ngwe, Kah Liang Gan
  • Patent number: 6696832
    Abstract: An apparatus and associated testing method for identifying void heads in magnetic storage systems in which a first bit error rate is determined using data written at a first overshoot amount. A second bit error rate is determined using data written at a second rate current in a second overshoot amount. A physically damaged transducer head is identified based upon a comparison of the first bit error rate to the second bit error rate.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: February 24, 2004
    Assignee: Seagate Technology LLC
    Inventors: Victor W K Chew, Edward Y K Hew, David K L Loh, Myint Ngwe, Wong Hon Leong, Say Kwee Teck