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:
Jul. 22, 2008
Filed:
Mar. 29, 2006
Sandeep Jain, Rewari, IN;
Jais Abraham, Malapurram, IN;
Sandeep Jain, Rewari, IN;
Jais Abraham, Malapurram, IN;
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
Scan tests tolerant to indeterminate states generated in an integrated circuit (IC) when employing signature analysis to analyze test outputs. Bits with indeterminate-state are masked when scanning out the bits from the scan chains to force such indeterminate bits to a known logic level. This prevents a signature generator receiving the outputs of a scan test from generating an invalid signature. In an embodiment, masking information is stored in encoded form in a memory. A decoding circuit decodes the masking information and provides mask data under control from a mask controller. Mask data is sent to a masking circuit which also receives corresponding bits from scan-out vectors, with each scan-out vector being generated by a corresponding one of multiple scan chains. The output of the masking circuit may be provided in a compressed form to the signature generator circuit.