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:
Apr. 21, 2009
Filed:
Sep. 15, 2004
Applicant:
Brion Keller, Binghamton, NY (US);
Inventor:
Brion Keller, Binghamton, NY (US);
Assignee:
Cadence Design Systems, Inc., San Jose, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 31/28 (2006.01);
U.S. Cl.
CPC ...
Abstract
During testing of an integrated circuit (IC), a channel masking capability is used for masking out unknown or unpredictable (X) values from being compressed into a signature register. The approach provides flexibility to allow for masking of unknown values, while avoiding many of the problems caused by over-masking of known values. The circuitry added to the design to allow for masking is reasonably small, and provides an effective way of masking unknown values during the testing process.