Patent ID: 7076707
Filing Date: 2006-07-11
Classification: G01R

Abstract:
1. A method of locating at least one a fault of a scan chain having a plurality of flip-flops in a logic integrated circuit of a configuration, comprising: an initial value collecting step of randomly selecting a plurality of logic integrated circuits with the same configuration, retrieving a plurality of initial value vectors of the flip-flops of every scan chain within said logic integrated circuits, and grouping together said initial value vectors into a plurality of corresponding scan chain sets, wherein said scan chain set contains scan chains with the same configuration: a golden pattern determining step of comparing each of the initial value vectors in the same corresponding scan chain set with each other to identify elements of the initial value vectors with fixed values and selecting the elements with the fixed values as a golden pattern for the corresponding scan chain set when the number of said elements reaches a predetermined percentage; and a fault locating step of comparing a plurality of initial values of a scan chain in question of a logic integrated circuit with the golden pattern found for the corresponding scan chain set that contains scan chains of the same configuration as the scan chain in question to determine whether the scan chain in question has at least one faulty flip-flop.