Patents by Inventor Yakov M. Lifchits

Yakov M. Lifchits 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: 8498076
    Abstract: In an embodiment of the present invention, a disk drive comprises a head actuated over a disk including 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 spiral track crossings. A plurality of timing recovery measurements are generated corresponding to the detected sync marks, and the timing recovery measurements are biased based on a radial location of the head. A servo write clock is generated in response to the biased timing recovery measurements, and the servo write clock is used to write product servo sectors to the disk.
    Type: Grant
    Filed: April 22, 2010
    Date of Patent: July 30, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Edgar D. Sheh, Yakov M. Lifchits, Charles A. Park
  • Patent number: 8432629
    Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of spiral tracks. A first sync frame is first opened in response to a first frame offset during a first revolution of the disk, wherein the first sync frame corresponds to the head approaching a first sync mark in a first spiral track crossing. A first sync frame position error signal (PES) is generated representing a difference between a target framing of the first sync frame around the first sync mark and a detected framing of the first sync frame around the first sync mark. The first frame offset is adjusted in response to the first sync frame PES, and during a second revolution of the disk the first sync frame is second opened in response to the adjusted first frame offset.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: April 30, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventors: Brian P. Rigney, Steven C. Smith, Yakov M. Lifchits, Boworn Panyavoravaj
  • Patent number: 7688539
    Abstract: A disk drive is disclosed comprising a disk, and a head actuated over the disk. The head is positioned at a radial location over the disk, and a servo burst is written at the current radial location. The servo burst is read to generate a read signal, and the read signal is processed to generate a position error signal (PES). The head is moved radially in response to the PES, and the process is repeated multiple times to form a spiral track spanning at least one revolution of the disk.
    Type: Grant
    Filed: May 14, 2008
    Date of Patent: March 30, 2010
    Assignee: Western Digital Technologies, inc.
    Inventors: Lawrence M. Bryant, Yakov M. Lifchits, Siri S. Weerasooriya
  • Patent number: 7602575
    Abstract: A disk drive is disclosed comprising control circuitry for self servo writing a disk. An estimated reader/writer offset is initialized, servo bursts in a first servo track are read, the head is moved radially using the estimated reader/writer offset, and propagated servo bursts are written to a target servo track. The propagated servo bursts are read from the target servo track to generate a read signal, the read signal is processed to generate a burst crossing signal (BCS), and the estimated reader/writer offset is adjusted in response to the BCS.
    Type: Grant
    Filed: May 14, 2008
    Date of Patent: October 13, 2009
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yakov M. Lifchits, Lawrence M. Bryant, Siri S. Weerasooriya, Wing Ying
  • 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