Patents Represented by Law Firm Stanger Stempler & Dreyfus
  • Patent number: 5140570
    Abstract: A track search circuit includes a command decoder which decodes command data sent by a microcomputer and stored in a command register and outputs signals commanding a track jump and commanding count of a counter which counts a tracking error signal. Time difference between a present A-time and a target A-time is calculated such that an optical pick-up can be moved toward a target position by utilizing the track jump of 4.sup.n. When a counted value of the counter reaches a predetermined value, the A-time is renewed such that the time difference can be reduced by addition or subtraction suitable time data to or from the A-time. If the renewed A-time becomes within 1 minute with respect to the target A-time in repeating such a track jump in accordance with the renewed A-time, the optical pick-up is stopped to move, and the A-time is read to jump the optical pick-up again to catch the target position.
    Type: Grant
    Filed: March 17, 1989
    Date of Patent: August 18, 1992
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Naobumi Nagasawa, Hiroyuki Arai