The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 17, 1988
Filed:
May. 11, 1987
Edward B Eichelberger, Hyde Park, NY (US);
Roger N Langmaid, New Fairfield, CT (US);
Eric Lindbloom, Poughkeepsie, NY (US);
Franco Motika, Hopewell Junction, NY (US);
John L Sinchak, Wappingers Falls, NY (US);
John A Waicukauski, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus for testing very large scale integrated circuit devices, most particularly Level Sensitive Scan Design (LSSD) devices, by applying differently configured sequences of pseudo-random patterns in parallel to each of the input terminals of the device under test, collecting the output responses from each of the output terminals in parallel, combining these outputs to obtain a signature which is a predetermined function of all of the sequences of parallel outputs and comparing the test signature with a known good signature obtained by computer simulation. The input test stimuli are further altered in a predetermined fashion as a function of the structure of the device to be tested, to individually weight the inputs in favor of more or less binary ones or zeros.