Patents by Inventor Hon Yu

Hon Yu 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).

  • Publication number: 20030179486
    Abstract: Provided are a method, system, and program for estimating coil resistance of a voice coil motor for an actuator assembly in a disk drive system. An estimation is made of a calibration coil resistance during a calibration operation. A determination is made of a distance moved during a seek operation. The determined distance and the calibration coil resistance are used to estimate a current coil resistance following the seek operation.
    Type: Application
    Filed: March 25, 2002
    Publication date: September 25, 2003
    Applicant: International Business Machines Corporation
    Inventors: Peter Kui Ho, Mantle Man-Hon Yu
  • Publication number: 20030151840
    Abstract: The present invention involves a recordable disk having a first plurality of S1 servo sample wedges in a first servo zone at an outermost position on the disk, a second plurality of S2 servo sample wedges in a second servo zone which is radially adjacent the first servo zone, and a third plurality of S3 servo sample wedges in a third servo zone which is radially adjacent the second servo zone. The S1 servo sample wedges of the first plurality are equally spaced apart circumferentially around the disk by a first angle &thgr;1, the S2 servo sample wedges of the second plurality are equally spaced apart circumferentially around the disk by a second angle &thgr;2=&thgr;1*N1, and the S3 servo sample wedges of the third plurality are equally spaced apart circumferentially around the disk by a third angle &thgr;3=&thgr;2*N2.
    Type: Application
    Filed: February 13, 2002
    Publication date: August 14, 2003
    Inventors: George Anthony Dunn, Mantle Man-Hon Yu
  • Patent number: 6594106
    Abstract: A system and method for adaptively compensating for real-time variations in mechanical dynamics of a head-positioning assembly during track follow and seek operations. The head-positioning assembly includes a voice coil actuator that positions a read/write head utilizing a coil and carriage in conformity with an actuator control signal. Variations in resonant mode characteristics are anticipated in real-time in accordance with measured temperature variations. These parametric variations are translated in real-time by a state space model to determine a secondary velocity and displacement of the read/write head during track follow and seek operations. In response to this secondary velocity and displacement determination, the actuator control signal is dynamically adjusted to compensate for the determined secondary head velocity and displacement, thereby improving head positioning accuracy and increasing servo bandwidth.
    Type: Grant
    Filed: October 29, 1999
    Date of Patent: July 15, 2003
    Assignee: International Business Machines Corporation
    Inventors: Louis Joseph Serrano, Mantle Man-Hon Yu, Kirk Barrows Price, Lei Zhang
  • Patent number: 6577463
    Abstract: A system and method for precompensating for tangential misalignment in a direct access storage device adjusts a SID timing window individually for every track or surface of the direct access storage device. The system and method generate a calculation of the tangential misalignment and adjust, in accordance with the calculation of tangential misalignment, a timing window during which the transducer head reads the information located on the storage surface. The calculation of tangential misalignment may be the result of a direct measurement of the tangential misalignment, or may be converted from radial misalignment data. The adjustment of the timing window may comprise opening the timing window an amount depending upon the degree of misalignment of each track, and may comprise shifting the window in time either forward or backward depending upon the nature of the calculated misalignment.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: June 10, 2003
    Assignee: International Business Machines Corporation
    Inventors: Gregory Michael Frees, Kirk Barrows Price, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Publication number: 20030098340
    Abstract: The invention provides a wire-bonding apparatus for forming electrical connections between a semiconductor chip and a leadframe, comprising a plurality of bond-heads associated with a plurality of work holders on said wire bonding apparatus for holding a plurality of leadframes, wherein each bond-head of the apparatus is capable of independent bonding operation simultaneously with the other bond-heads, without synchronization of movement with the other bond-heads.
    Type: Application
    Filed: November 28, 2001
    Publication date: May 29, 2003
    Applicant: ASM Technology Singapore Pte Ltd
    Inventors: Yam Mo Wong, Keng Yew Song, Ka Shing Kwan, Hon Yu Ng, Tin Kwan Chan
  • Patent number: 6563657
    Abstract: A hard disk drive for a computer system has at least two actuators for reading data from or writing data to the disks. The actuators may be configured to support the different methods of data access required of them. For example, if large quantities of sequential data are performed, one operation uses both actuators to increase throughput. However, if mostly random operations are to be performed, then independent usage of the actuators is preferred. These two methods of usage can be supported simultaneously, and can even be dictated by the user. The tracking format of the actuators can be configured such that the next logical track is physically located under a head on a different actuator to improve sequential operation. The actuators also may be utilized in a dual-channel configuration so that data can be written to both actuators at the same time, or read back at the same time to improve throughput. In addition, either of these configurations can be selected on a transfer-by-transfer basis by the user.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: May 13, 2003
    Assignee: International Business Machines Corporation
    Inventors: Louis Joseph Serrano, Mantle Man-Hon Yu, Kirk Barrows Price
  • Patent number: 6522495
    Abstract: In summary, preferred embodiments disclose a system, method, and program for determining a value for non-mechanical noise within a disk drive system. The non-mechanical noise is likely related to instability in a head which reads data from a magnetic surface within the disk drive system. First, a sample of position error signals (PES) indicating non-repeatable runouts (NRRO) is provided from read operations within the disk drive system. Spectral analysis is then performed on the provided samples to calculate non-filtered power values for the NRRO values at different frequencies. A filtered power spectrum is determined within a frequency range excluding mechanical noise. A filtered power value is calculated from the determined filtered power spectrum within the frequency range excluding mechanical noise.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: February 18, 2003
    Assignee: International Business Machines Corporation
    Inventors: Bernd Lamberts, Mantle Man-Hon Yu
  • Patent number: 6519109
    Abstract: A method and apparatus for providing feedforward control of two interacting actuators to compensate for interaction there between is disclosed. State models for each actuator that processes acceleration for each actuator provide an estimate of head acceleration for each of the actuators and to provide feedforward control signals to the actuators for controlling the positioning of the heads based upon the estimates of head acceleration for each of the actuators.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: February 11, 2003
    Assignee: International Business Machines Corporation
    Inventors: Kirk Barrows Price, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Patent number: 6469855
    Abstract: A method and system in accordance with the present invention for minimizing the loss of data by a write head is disclosed. The method comprises providing a desired write head width based upon a hard error rate. The method further comprises adjusting at least one parameter of the servo control logic based upon a comparison of the width of the write head and the desired write head width, wherein the write head will not exceed the hard error rate when writing data. Through the use of a system and method in accordance with the present invention a servo system can be designed based on a constant hard error rate. The write inhibit window and the settle delay for writing operations in a servo system will be optimized, based on the hard error rate, for each individual head in the disk drive configuration. This will increase the speed of the servo process without affecting the reliability of the data.
    Type: Grant
    Filed: April 30, 1999
    Date of Patent: October 22, 2002
    Assignee: International Business Machines Corporation
    Inventors: Bernd Lamberts, Mantle Man-Hon Yu, Louis Joseph Serrano
  • Patent number: 6462898
    Abstract: There is disclosed an error correction and detection method and apparatus for retreiving predetermined data, e.g. servo data, from the position error signal (PES) fields of a disk in a data storage system . In the preferred embodiment the PES data such as the track number is mapped into codewords of an error correction code (ECC) which are then further divided into a set of symbols which are mapped onto a second set of bit vectors which have a constant weight. The preferred encoding method is selected to equalize the analog signal characteristics of the PES fields so that minimal, if any, change in the conventional servo detection circuitry needed to use the PES fields of the invention both as analog and digital information.
    Type: Grant
    Filed: June 16, 1998
    Date of Patent: October 8, 2002
    Assignee: International Business Machines Corporation
    Inventors: Mario Blaum, William John Kabelac, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Patent number: 6456450
    Abstract: A method and apparatus for reducing track misregistration due to digital-to-analog converter quantization noise. In hard disk drive (HDD) servo control systems, quantization noises (or roundoff errors) due to the finite precision of the D/A converter (DAC) driving the VCM contribute a significant portion of the total track-misregistration (TMR). The present invention provides a quantization error feedback (QEF) technique to reduce TMR due to DAC quantization noises. The QEF technique according to the present invention offers a simple method of reshaping the spectrum of this noise to minimize its contribution to TMR. In the digital signal processor (DSP) implementation of the QEF schemes, the quantization error is monitored and accumulated in the DSP; when sufficient error has accumulated, the MSB feeding the DAC are modified such as to cancel the effect of the error.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: September 24, 2002
    Assignee: International Business Machines Corporation
    Inventors: Wei-Min Lu, Roger William Wood, Mantle Man-Hon Yu
  • Patent number: 6426843
    Abstract: A method, apparatus, and article of manufacture for rotational position reordering of queued commands in a data storage device based on settle time estimator feedback. An initial settle time estimation is programmed into a servo controller for the data storage device. As data operations are performed in the data storage device, an actual settle time is measured for the data operations, generally through the use of a timer in the servo controller. The settle time estimation is then modified based on the actual settle time and the data operations are reordered or scheduled based on the settle time estimation. Specifically, the settle time estimation is adjusted based on a success rate for the data operations, wherein the success rate comprises a comparison of the actual settle time versus the settle time estimation.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: July 30, 2002
    Assignee: International Business Machines Corporation
    Inventors: Bernd Lamberts, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Publication number: 20020094783
    Abstract: A space shift keying (SSK) modulation is disclosed. At the transmitter of a digital wireless communication with an antenna array, due to the fact that multipath fading will cause different responses for distinct array elements, different information signal bits (such as the “0” and “1” in binary shift keying) can be sent from different array elements to the receiver site. At the receiver site, the likelihood ratio test can be used to recognize the information signal bits transmitted from different array elements. The present signaling method for carrying information signal bits is a digital modulation method, which is known as space shift keying modulation.
    Type: Application
    Filed: November 7, 2001
    Publication date: July 18, 2002
    Inventors: Yawgeng Chau, Shi-Hon Yu
  • Patent number: 6421198
    Abstract: Linearity compensation is provided for a position error signal based on repeatable and non-repeatable run out in a data storage device. The run out is measured on a track of the data storage device at a plurality of points, such as a track center and one or more points offset from the track center. The run out is typically measured using either an unstitched primary position error signal or an unstitched quadrature position error signal. The offsets are usually stitch points for the position error signal. A component of the run out is extracted at the points, wherein the component generally comprises one or more characteristics of the run out, such as a frequency, a set of frequencies, a root mean square, or some other characteristic of the run out. The linearizing equation to be used for the position error signal is identified based on the measured run out and generally comprises a polynomial function.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: July 16, 2002
    Assignee: International Business Machines Corporation
    Inventors: Bernd Lamberts, Louis Joseph Serrano, Markus Staudenmann, Mantle Man-Hon Yu
  • Patent number: 6412058
    Abstract: A system, method, and article of manufacture for adaptive re-mapping of head addresses in a data storage device. A logical address received by the data storage device is converted into a corresponding physical address, such as cylinder or track, read/write head, and sector. The selection of the read/write head is then re-mapped by the data storage device to a more optimal selection. Thereafter, the desired operation can be performed using the physical address including the re-mapped selection of the read/write heads.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: June 25, 2002
    Assignee: International Business Machines Corporation
    Inventors: George Robert Houston, Bernd Lamberts, Mantle Man-Hon Yu
  • Patent number: 6388832
    Abstract: Method and system aspects for controlling spindle motor speed during head loading in a disk drive are described. The aspects include inputting a time-varying reference velocity profile signal, and selecting a controller to control spindle motor speed. Further included is feeding forward control signals sufficient to precompensate for drag during a head loading event and maintain spindle motor speed within an operating tolerance.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: May 14, 2002
    Assignee: International Business Machines Corporation
    Inventors: Jeffrey Joseph Dobbek, Bryan Scott Rowan, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Patent number: 6384998
    Abstract: A method, apparatus, and article of manufacture for controlling a disk drive with multiple VCMs is disclosed. The apparatus comprises a first disk storage surface and a second disk storage surface. The first disk storage surface has a plurality of first data segments and a plurality of first servo track segments interspersed therebetween, and is readable and writeable by a first head controllable according to a first servo track signal read from at least one of the first servo track segments. The second disk storage surface has a plurality of second data segments and a plurality of second servo track segments interspersed therebetween, and is readable and writeable a second head separately controllable from the first head according to a second servo track signal read from at least one of the plurality of second servo track segments.
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: May 7, 2002
    Assignee: International Business Machines Corporation
    Inventors: Kirk Barrows Price, Mantle Man-Hon Yu
  • Publication number: 20020046317
    Abstract: A system, method, and article of manufacture for adaptive re-mapping of head addresses in a data storage device. A logical address received by the data storage device is converted into a corresponding physical address, such as cylinder or track, read/write head, and sector. The selection of the read/write head is then re-mapped by the data storage device to a more optimal selection. Thereafter, the desired operation can be performed using the physical address including the re-mapped selection of the read/write heads.
    Type: Application
    Filed: April 27, 1999
    Publication date: April 18, 2002
    Inventors: GEORGE ROBERT HOUSTON, BERND LAMBERTS, MANTLE MAN-HON YU
  • Patent number: 6362766
    Abstract: A variable pulse pulse width modulation digital-to-analog converter comprising: an input code register to store a digital input code to be converted; a PWM decoder, coupled to the input code register, to convert the input code to a series of pulses; an output driver circuit coupled to the PWM decoder, wherein the output driver circuit generates an output signal comprising pulses of a high logic level and pulses of an intermediate logic level; and a filter to integrate the pulses to generate an analog output value corresponding to the digital input code. In one embodiment, the output stage comprises an active tri-state driver, a multiplexer and at least two output reference voltage sources. Using a plurality of different amplitude pulse levels enables PWM DACs according to the present invention to provide greater resolution than conventional PWM DACs for a given clock frequency and conversion period.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: March 26, 2002
    Assignee: International Business Machines Corporation
    Inventors: Bryan Scott Rowan, Louis Joseph Serrano, Mantle Man-Hon Yu
  • Publication number: 20010024335
    Abstract: There is disclosed an error correction and detection method and apparatus for retreiving predetermined data, e.g. servo data, from the position error signal (PES) fields of a disk in a data storage system. In the preferred embodiment the PES data such as the track number is mapped into codewords of an error correction code (ECC) which are then further divided into a set of symbols which are mapped onto a second set of bit vectors which have a constant weight. The preferred encoding method is selected to equalize the analog signal characteristics of the PES fields so that minimal, if any, change in the conventional servo detection circuitry needed to use the PES fields of the invention both as analog and digital information.
    Type: Application
    Filed: June 16, 1998
    Publication date: September 27, 2001
    Inventors: MARIO BLAUM, WILLIAM JOHN KABELAC, LOUIS JOSEPH SERRANO, MANTLE MAN-HON YU