Patents by Inventor John D. Drummond

John D. Drummond 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: 5907510
    Abstract: This invention is useful in column multiplexed memories, particularly static random access memories (SRAM) used in application specific integrated circuits (ASIC) . These column multiplexed memories include memory cells disposed in rows and columns. For writes all the bitlines are connected to a bias generator. The bias generator uses first P-channel field effect transistor and a first N-channel field effect transistor connected in series with their junction connected to the bitline. The bias generator is driven by a bias enable pulse that is active for a short time before the write time. Normally these field effect transistors are biased OFF by a second P-channel field effect transistor and a second N-channel field effect transistor. Another pair of N-channel field effect transistors connect the bases of the first P-channel field effect transistor and the first N-channel field effect transistor together to the bitline when the bias enable pulse is active.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: May 25, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Bryan D. Sheffield, John D. Drummond
  • Patent number: 4471161
    Abstract: A conductor strand 12 for an electric cable 10 is disclosed. The conductor strand includes a solid first wire 16 having a longitudinal axis A.sub.1, an inner layer of six solid wires 20 twisted helically about the first wire and an outer layer 24 formed of two different diameter wires. The outer layer includes six third wires 26 spaced circumferentially one from the other leaving a gap G therebetween. Disposed in each gap is a fourth wire 28 having a diameter which lies in a range of sixty-eight percent to seventy-eight percent of the diameter of the third wire. A method for making the cable is disclosed which includes the steps of helically twisting the inner layer about the first wire with a lay greater than the lay of the finished conductor, twisting the outer layer of wires about the inner layer of wire with that greater lay, and twisting the outer and inner wires about the first wire to reduce the lay to the lay of the finished conductor strand.
    Type: Grant
    Filed: February 16, 1983
    Date of Patent: September 11, 1984
    Assignee: Essex Group, Inc.
    Inventor: John D. Drummond