Patents by Inventor C. John Grebenkemper

C. John Grebenkemper 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: 6366972
    Abstract: A multi-user bus is divided into a number of bus portions, one for each user. Each bus portion is coupled, at one end, to one of the multiple users and through an impedance matching network to the other bus portions in a star configuration. The disclosed embodiment teaches various resistive impedance matching networks.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: April 2, 2002
    Assignee: Compaq Computer Corporation
    Inventors: C. John Grebenkemper, Dong Nguyen
  • Patent number: 5958034
    Abstract: A method for manufacturing a bus having enhanced signals qualities which includes the steps of determining the intrinsic inductance per unit length (L.sub.0) and intrinsic capacitance per unit length (C.sub.0) of the unloaded bus. The method also includes the step of determining the load capacitance per unit length (C.sub.d) of the bus that is attributable to the peripheral devices that will be attached to the bus. Based on these values, an adjustment inductance (L.sub.d) per unit length for the bus is calculated for the bus with L.sub.d being substantially equal to L.sub.0 * C.sub.d /C.sub.0. Finally, one inductor of value L.sub.d is added per unit length of the bus. The added adjustment inductance offsets the capacitance attributable to the peripheral devices attached to the bus. The result is that signals within the bus have rise and fall times acceptable for high speed operation.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: September 28, 1999
    Assignee: Compaq Computer Corporation
    Inventors: Jack An-Kou Shiao, C. John Grebenkemper, Frank Mikalauskas
  • 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