Patents Represented by Attorney, Agent or Law Firm Howard H. Sheerin
  • Patent number: 7471483
    Abstract: A disk drive is disclosed comprising a disk, and a head actuated radially over the disk. A first linear acceleration signal is generated representing a first acceleration disturbance, a second linear acceleration signal is generated representing a second acceleration disturbance, and a third linear acceleration signal is generated representing a thermal popping disturbance. The first linear acceleration signal is combined with the third linear acceleration signal to generate a fourth linear acceleration signal representing a combined physical shock disturbance and thermal popping disturbance.
    Type: Grant
    Filed: September 19, 2007
    Date of Patent: December 30, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Timothy A. Ferris, Alain Chahwan
  • Patent number: 7468855
    Abstract: A method is disclosed of writing product servo sectors to a disk of a disk drive to define a plurality of product servo wedges, the disk comprising a plurality of spiral tracks. The spiral tracks are spaced apart circumferentially by a substantially equal spacing, and the number of spiral tracks equals a non-integer multiple of product servo wedges. The head internal to the disk drive is used to read the spiral tracks to generate a read signal, and the sync marks are detected from the read signal to generate a sync mark detect signal. A timing recovery measurement is generated in response to the sync mark detect signal, and a frequency control signal is generated in response to the timing recovery measurement. A servo write clock is generated in response to the frequency control signal which is used to write the product servo sectors to the disk.
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: December 23, 2008
  • Patent number: 7461352
    Abstract: This invention provides systems and methods for displaying and controlling the content of a second graphical application window while in a first graphical application window in a windowed computing environment having a voice recognition engine. The present invention enables a computer user working in a graphical application window to use speech commands to open, view, retrieve, and control help, Internet, and other information in a second graphical application window. Thus, the invention allows a user to keep a first graphical application window open and in focus while simultaneously viewing a second graphical application window; thereby allowing a user to proceed with his/her work while actively opening, positioning, viewing and controlling the content of a second graphical application window containing help, Internet, or other information.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: December 2, 2008
    Inventor: Ronald Mark Katsuranis
  • Patent number: 7457071
    Abstract: An embodiment of the present invention comprises a method of writing product servo sectors to a disk of a disk drive. The disk comprises a plurality of spiral tracks each having a high frequency signal interrupted at a predetermined interval by a sync mark. The head internal to the disk drive is used to read the spiral tracks to generate a read signal which is processed to detect the sync marks. An aberration is detected in the detected sync marks in order to locate an initial radial location of the head with respect to the disk. The read signal representing the high frequency signal in the spiral tracks is processed to generate a position error signal (PES) used to maintain the head along a substantially circular target path while using the head internal to the disk drive to write the product servo sectors along the circular target path.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: November 25, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Edgar D. Sheh
  • Patent number: 7453661
    Abstract: A method of servo writing a disk of a disk drive is disclosed, wherein the disk drive comprising the disk and a head actuated over the disk. Servo sectors are written to define servo tracks from a first diameter of the disk to substantially a middle diameter of the disk, wherein the first diameter is selected from one of the outer and inner diameter of the disk. Servo sectors are then written to define servo tracks from a second diameter of the disk toward the middle diameter of the disk by positioning the head over a current servo track, reading the current servo track to generate a read signal, processing the read signal to detect a previously written servo sector, and if a previously written servo sector is not detected, then writing servo sectors to the current servo track and positioning the head over a next servo track.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: November 18, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Jinsheng Bill Jang, Shih Min Liu
  • Patent number: 7451344
    Abstract: A method is disclosed for ordering error recovery steps of an error recovery procedure executed by a disk drive, wherein each error recovery step having an execution time. The disk drive comprises a disk having a plurality of tracks, wherein each track comprises a plurality of data sectors. A plurality of step success counters are initialized, wherein each counter corresponds to one of the error recovery steps. A plurality of the error recovery steps are executed, wherein if an error recovery step successfully recovers one of the data sectors the corresponding step success counter is incremented. A step priority value is computed for each error recovery step in response to the step success counter and execution time for each step. The error recovery steps are then ordered in response to the step priority values.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: November 11, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Michael S. Rothberg
  • Patent number: 7450334
    Abstract: A disk drive is disclosed including a disk having a plurality of tracks, wherein each track comprises a plurality of data sectors. The disk drive further comprises a head coupled to a distal end of an actuator arm, and a voice coil motor (VCM) comprising a voice coil for rotating the actuator arm about a pivot. A read command is selected from a command queue, wherein the read command comprises a requested data sector. A maximum number of additional data sectors is determined that may be cached together with the requested data sector. An actual number of additional data sectors to cache is selected in response to the maximum number and a temperature of the voice coil.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: November 11, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Zhi Wang, Kenny T. Coker
  • Patent number: 7440225
    Abstract: A disk drive is disclosed including a disk having a plurality of servo tracks, wherein each servo track comprises a plurality of servo sectors forming N servo wedges, and a wedge time period (WTP) occurs between each servo wedge. A VCM control signal is generated by generating an estimated WTP by detecting the servo sectors, estimating a pivot velocity in response to the estimated WTP, the pivot velocity representing a velocity of an actuator arm about a pivot, generating a pivot friction compensation in response to the estimated pivot velocity, and generating the VCM control signal in response to the pivot friction compensation.
    Type: Grant
    Filed: August 21, 2006
    Date of Patent: October 21, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Min Chen, Zhi Wang
  • Patent number: 7440210
    Abstract: A method of writing spiral tracks on a disk of a disk drive is disclosed. The disk drive comprises control circuitry and a head disk assembly (HDA) comprising the disk, an actuator arm, a head coupled to a distal end of the actuator arm, and a voice coil motor for rotating the actuator arm about a pivot to position the head radially over the disk. A write clock is synchronized to the rotation of the disk, and a plurality of spiral tracks are written on the disk at a predetermined circular location determined from the write clock. Each spiral track comprises a high frequency signal interrupted at a predetermined interval by a multi-bit sync mark, and each multi-bit sync mark comprises a plurality of bits.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: October 21, 2008
  • Patent number: 7436610
    Abstract: A disk drive is disclosed comprising a plurality of disk surfaces, including first and second disk surfaces. A first physical zone on a first disk surface has a physical zone boundary at a first predetermined radial location, wherein the first predetermined radial location is different from any of the radial locations of the physical zone boundaries on a second disk surface. A plurality of logical zones are identified having logical zone boundaries defined relative to the physical zone boundaries of at least the first and second disk surfaces, wherein the number of logical zones is greater than the number of physical zones for at least one of the disk surfaces. The logical zones are used to find one of the data sectors corresponding to a block address received from a host.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: October 14, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Gregory B. Thelin
  • Patent number: 7437502
    Abstract: A disk drive is disclosed comprising a disk, a head actuated over the disk, and a history array for storing a plurality of history records, wherein each history record having a history range identifying a range of sector addresses proximate the sector address of a host command. As new host commands are received, the sector address of each host command is compared to the history records in the history array. A counter is adjusted in response to each comparison, and an operating mode of the disk drive is configured into a new operating mode if the counter exceeds a threshold, wherein the configuring includes adjusting at least one of the history range and the threshold relative to the new operating mode.
    Type: Grant
    Filed: April 20, 2005
    Date of Patent: October 14, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Kenny T. Coker
  • Patent number: 7433143
    Abstract: A method and apparatus is disclosed for adjusting the track density by changing the slope of spiral tracks used to servo write a disk drive. A target track density is established for a disk surface, and a plurality of spiral tracks are written to the disk surface in response to the target track density. Each spiral track comprises a high frequency signal interrupted at a predetermined interval by a sync mark, and a slope of the spiral tracks is selected in response to the target track density. The head internal to the disk drive is used to read the spiral tracks in order to write product servo sectors to the disk to define a plurality of data tracks, wherein the slope of the spiral tracks determines the density of the data tracks.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: October 7, 2008
  • Patent number: 7406545
    Abstract: An information storage device is disclosed (such as a disk drive) comprising an interface for connecting to a host through a cable, and control circuitry for communicating with the host over the cable by executing a communication process. The communication processes comprises the steps of transmitting a communication request to the host over the cable and waiting to receive a response from the host over the cable. A cable loss event is logged if the host fails to respond after executing the communication process at least twice. Performing the communication process multiple times before logging a cable loss event helps ensure a communication failure is actually due to a faulty cable connection.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: July 29, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Michael S. Rothberg, Donald L. McKeefery, Anthony C. Geria, Jan G. Abrahamsson, Andrew Hill
  • Patent number: 7391584
    Abstract: A method of servo writing a disk of a disk drive is disclosed. The disk comprises a plurality of spiral tracks, wherein each spiral track comprises a high frequency signal interrupted periodically by a sync mark. A timing recovery measurement is generated in response to the sync marks, wherein the timing recovery measurement comprises a sinusoidal component. A timing compensation value is generated in response to the sync marks which estimates the sinusoidal component in the timing recovery measurement. A frequency control signal is generated in response to the timing recovery measurement and the timing compensation value, a servo write clock is generated in response to the frequency control signal, and the servo write clock and the head internal to the disk drive are used to write the product servo sectors to the disk.
    Type: Grant
    Filed: November 7, 2006
    Date of Patent: June 24, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Edgar D. Sheh, Yilin Cai
  • Patent number: 7391583
    Abstract: A method of writing product servo sectors to a disk of a disk drive is disclosed. The disk comprises a plurality of spiral tracks, wherein each spiral track comprises a high frequency signal interrupted at a predetermined interval by a sync mark. The read signal from the head is processed to detect a plurality of the sync marks in a spiral track crossing. A timing recovery measurement is generated in response to a selected one of the sync marks based on reliability metrics, wherein a servo write clock is synchronized in response to the timing recovery measurement. The read signal representing the high frequency signal in the spiral track crossing is processed to generate a position error signal (PES) used to maintain the head along a substantially circular target path while using the servo write clock to write product servo sectors along the circular target path.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: June 24, 2008
  • Patent number: 7380147
    Abstract: A computer device is disclosed comprising at least one component operable to process commands at command intervals, and control circuitry operable to set an idle mode timeout interval. The control circuitry stores a plurality of the command intervals, and then evaluates the command intervals to set the timeout interval by finding a qualifying number of the command intervals that fall within a sliding window. The component is configured into an idle mode if a most recent command interval exceeds the timeout interval. In this manner, after entering the idle mode the probability that the next command will be processed within the sliding window is reduced, thereby helping to optimize power consumption.
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: May 27, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: Ye Sun
  • Patent number: 7369340
    Abstract: A disk drive is disclosed comprising a disk having top and bottom surfaces, and top and bottom heads actuated over the top and bottom surfaces, respectively. Control circuitry detects a warping of the disk by writing a first test pattern to the top surface, reading the first test pattern to generate a first read signal, monitoring a first read signal value proportional to an amplitude of the first read signal, writing a second test pattern to the bottom surface, reading the second test pattern to generate a second read signal, monitoring a second read signal value proportional to an amplitude of the second read signal, and processing the first and second read signal values to detect a negative correlation between the amplitudes of the first and second read signals.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: May 6, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Dean V. Dang, Philip Bernard Saram, Chakrit Choosang, Jonas A. Goode
  • Patent number: 7369343
    Abstract: A disk drive is disclosed comprising a head actuated over a disk having a plurality of servo tracks, wherein each servo track comprises a plurality of servo sectors and each servo sector comprises a track address. A read signal from the head representing a first track address in one of the servo sectors is processed in order to generate a detected track address which is compared to a first target track address to obtain a first track address error. A correction metric is generated representing a likelihood that the first track address error was caused by a detection error, and if the correction metric exceeds a threshold, the detected track address is corrected in response to the first track address error, and the write operation is continued. If the correction metric does not exceed the threshold, the write operation is aborted.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: May 6, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Teik E E Yeo, Weiping Chen Jiang
  • Patent number: 7333280
    Abstract: A method of writing product servo sectors on a disk of a disk drive is disclosed. The disk comprises a reference pattern having a plurality of sync marks written around the disk. The sync marks are detected to generate a sync mark detect signal, and a timing recovery measurement is generated in response to the sync mark detect signal. A frequency control signal is generated in response to the timing recovery measurement, and a servo write clock is generated in response to the frequency control signal. A feed-forward compensation value is generated in response to the timing recovery measurement and the frequency control signal, and the timing recovery measurement is adjusted in response to the feed-forward compensation value to compensate for a repeatable phase error in the timing recovery measurement. The servo write clock and the head internal to the disk drive are used to write the product servo sectors to the disk.
    Type: Grant
    Filed: August 3, 2004
    Date of Patent: February 19, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yakov M. Lifchits, Wing Ying, Yilin Cai, Siri S. Weerasooriya
  • Patent number: 7330019
    Abstract: A discontinuous switching voltage regulator is disclosed including a charging element operable to generate an output voltage, switching circuitry coupled to the charging element, and switch control circuitry to configure the charging element during a cycle, including to charge the charging element for an on-time, discharge the charging element for a discharge time, and tristate the charging element for a tristate time. In operation, the on-time is initialized to a first on-time, and a first switch time is measured comprising the first on-time and a first discharge time of a first cycle. A first tristate time of the first cycle is measured, and a first ratio of the first tristate time to the first switch time is determined. The first ratio is compared to a first ratio threshold, and the on-time is adjusted to a second on-time if the first ratio exceeds the first ratio threshold.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: February 12, 2008
    Assignee: Western Digital Technologies, Inc.
    Inventor: George J. Bennett