Patents by Inventor Ralph Charles Mitchell

Ralph Charles Mitchell 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: 4084152
    Abstract: This specification describes arrays for performing logic functions. In these arrays input variables are placed on a series of parallel input lines that intersect a number of parallel output lines in a grid of intersections. Field effect devices at these intersections have their gate terminals connected to one of the input lines and their source terminal connected to one of the output lines and through a load device to a source of potential. The drain terminals of these devices are either unconnected, connected directly to ground or connected to ground through one of two switching devices. The devices with unconnected drains are inoperative. The devices with their drains connected directly to ground are operative at all times. While the devices connected to ground through one of the switches are operative only when the switch is closed. The array can be time shared by two different logic functions by having one or the other of the switches off at any given time.
    Type: Grant
    Filed: April 4, 1977
    Date of Patent: April 11, 1978
    Assignee: International Business Machines Corporation
    Inventors: Gerald Bernard Long, Ralph Charles Mitchell, Shing Chou Pi