Patents by Inventor Robert C. Letteney

Robert C. Letteney 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: 4228520
    Abstract: A high speed multiply apparatus minimizes latch requirements and I/O pin requirement between chips by a new configuration which iteratively adds four multiples of a multiplicand in a stage of 4-2 carry save adders which then feed four-bit parallel adders each having four sum outputs and a carry output from the highest order bit position. Only the sum outputs are latched and then fed to a carry propagate adder on each iteration for addition to the previous partial products. Only the single carry output from each of the 4-bit parallel adders needs to be latched and then fed to another 4-bit parallel adder.
    Type: Grant
    Filed: May 4, 1979
    Date of Patent: October 14, 1980
    Assignee: International Business Machines Corporation
    Inventors: Robert C. Letteney, Samuel R. Levine, David T. Shen, Arnold Weinberger