Patents by Inventor David R. Huffman

David R. Huffman 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: 4719600
    Abstract: An improved sense circuit for determining the data state of a memory cell in a multilevel storage system is disclosed. The sense circuit includes at least two differential voltage level sensing circuits. A first differential voltage level sensing circuit compares the relative magnitudes of a data input signal voltage level corresponding to a particular memory cell charge level and a first reference voltage level, thereby providing at least one first binary data output signal. The first binary data output signal is then used to generate a second reference voltage level having a magnitude different from that of the first reference voltage level. A second differential voltage sensing level circuit compares the relative magnitudes of an adjusted data input signal voltage level and a second reference voltage level, thereby providing at least one second binary data output signal. The adjusted data input signal corresponds to a function of the first data input signal.
    Type: Grant
    Filed: February 18, 1986
    Date of Patent: January 12, 1988
    Assignee: International Business Machines Corporation
    Inventors: David R. Huffman, Scott C. Lewis, James E. Rock