Patents by Inventor Duc N. Le

Duc N. Le 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: 5539328
    Abstract: To minimize skew and jitter imposed upon signals communicated along a printed circuit signal path a termination circuit is formed proximate the sink or receiving element of the signals. The termination circuit can be resistive, coupling the signal path to a supply power and to a ground potential.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: July 23, 1996
    Assignee: Tandem Computers Incorporated
    Inventors: Russell N. Mirov, Duc N. Le, Frank Mikalauskas, C. John Grebenkemper, Kinying Kwan
  • Patent number: 5491442
    Abstract: A clock generator produces a plurality of clock signals from a master clock and a delayed clock version of the master clock by applying a division of the delayed version of the master clock to the data input of a flip-flop and clocking the flip-flop with the master clock. A number of plurality of clock signals are produced by applying the output of the flip-flop to the data input of an array of second flip-flops--one flip-flop of the array for each of the number of clock signals--that are clocked by the delayed version of the master clock.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: February 13, 1996
    Assignee: Tandem Computers Incorporated
    Inventors: Russell N. Mirov, Duc N. Le, Frank Mikalauskas, C. John Grebenkemper, Kinying Kwan
  • Patent number: 5461332
    Abstract: A clock generator system for producing a number of multiple frequency digital clock signals for distribution to a number of synchronous, clocked devices, include two separate, substantially identically structured clock generator units that operate in lock-step unison. The digital clock signal outputs of one of the generator units are distributed to the synchronous, clocked devices and to an error detection circuit, that also receives the digital clock signals from other clock generator unit for comparison with one another. In the event an error is detected, the error detection circuit will produce an error signal to halt operation of the system with which the clock generator system is used, and reset the clock generator.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: October 24, 1995
    Assignee: Tandem Computers Incorporated
    Inventors: Russell N. Mirov, Duc N. Le, Frank Mikalauskas, C. John Grebenkemper, Kinying Kwan
  • Patent number: 5371417
    Abstract: A clock generator system for producing a number of multiple frequency digital clock signals for distribution to a number of synchronous, clocked devices, include two separate, substantially identically structured clock generator units that operate in lock-step unison. The digital clock signal outputs of one of the generator units are distributed to the synchronous, clocked devices and to an error detection circuit, that also receives the digital clock signals from other clock generator unit for comparison with one another. In the event an error is detected, the error detection circuit will produce an error signal to halt operation of the system with which the clock generator system is used, and reset the clock generator.
    Type: Grant
    Filed: July 2, 1993
    Date of Patent: December 6, 1994
    Assignee: Tandem Computers Incorporated
    Inventors: Russell N. Mirov, Duc N. Le, Frank Mikalauskas, C. John Grebenkemper, Kinying Kwan
  • Patent number: 5036528
    Abstract: The present invention is directed to a self-calibrating clock synchronization system that receives a periodic, digital clock signal as a reference and generates therefrom a system clock signal that dynamically tracks and is synchronized to the reference clock. The invention utilizes state machine controlled selection circuitry that comprises a plurality of predetermined delays tapped to produce a number of phase-related clock signals, and multiplexing circuitry, for selecting one of the plurality of clock signals as the system clock. A comparator compares the selected clock signal and the reference clock to determine which leads or lags the other. In response to the comparison, selection, from the plurality of clock signals, of a system clock that most clearly matches the reference signal is made.
    Type: Grant
    Filed: January 29, 1990
    Date of Patent: July 30, 1991
    Assignee: Tandem Computers Incorporated
    Inventors: Duc N. Le, Lordson L. Yue, Cirillo L. Costantino, David P. Chengson, Duc N. Le, Lordson L. Yue, Aurangzeb K. Khan