Patents Assigned to International Business Machine Company
  • Testing embedded arrays in large scale integrated circuits
    Patent number: 4404519
    Abstract: An integrated circuit chip having an embedded array which is not directly accessible from the primary input/output chip pins is manufactured with additional test circuitry directly on the chip, such that the performance of the array may be physically tested from the input/output pins by an external chip tester while the array remains embedded. Because of the added test circuitry, tests are not limited to the original chip architecture, and a variety of array tests may be made by an external tester without redesigning the chip architecture.
    Type: Grant
    Filed: December 10, 1980
    Date of Patent: September 13, 1983
    Assignee: International Business Machine Company
    Inventor: Douglas W. Westcott