Patents by Inventor Greg T. Sullivan

Greg T. Sullivan 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: 5731725
    Abstract: A precision delay circuit in an integrated circuit chip includes a transistor switching circuit in combination with a control circuit and a compensation circuit. The transistor switching circuit receives an input signal; and in response, the transistors switch on and off at an unpredictable speed to generate an output signal with a delay that has a large tolerance. The control circuit estimates the unpredictable speed at which the transistors switch and it generates control signals that identify the estimated speed. The compensation circuit includes a plurality of compensation components for the transistor switching circuit. This compensation circuit receives the control signals from the control circuit; and in response, it selectively couples the compensation components to the transistor switching circuit such that the combination of the transistors and the selectively coupled components generates the output signal with a precise delay that has an insignificant tolerance.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: March 24, 1998
    Assignee: Unisys Corporation
    Inventors: Roland D. Rothenberger, Greg T. Sullivan, Kenny Yifeng Tung
  • Patent number: 5594690
    Abstract: A memory in an integrated circuit chip includes an array of memory cells and a read/write circuit which performs precharge and sense operations on the array for a time interval that is set by the width of a pulse signal. This pulse signal is generated by a pulse generator circuit which contains transistors that switch on and off at an unpredictable speed; and consequently, the width of the pulse signal has a large tolerance. To decrease this large tolerance in the pulse signal, a compensation circuit is provided which includes a plurality of compensation components for the pulse generator. This compensation circuit selectively couples the compensation components to the pulse generator such that the selectively coupled components in combination with the pulse generator's transistors produce the pulse signal with a precise width that has an insignificant tolerance.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: January 14, 1997
    Assignee: Unisys Corporation
    Inventors: Roland D. Rothenberger, Greg T. Sullivan, Kenny Y. Tung