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:
Aug. 27, 1991
Filed:
May. 18, 1989
Vishwani D Agrawal, New Providence, NJ (US);
Kwang-Ting Cheng, North Plainfield, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A method of partial scan design for chip testing and a circuit produced in accordance with the method in which the selection of scan memory elements eliminates cycles in the circuit while the circuit is in a test mode. Cycles are defined as feedback paths from an output of a memory element to an input of the memory element. Cycle length is the number of memory elements in a feedback path. Experimental data suggests that test complexity grows exponentially with the cycle length. By eliminating cycles of desired lengths, the set of scan memory elements may be only a small fraction of the total memory elements of a circuit.