Non-destructive analysis to determine use history of processor

Abstract

A method and system are provided for chip testing. The method includes ascertaining a baseline for a functioning chip with no stress history by performing a non-destructive test procedure on the functioning chip. The method further includes repeating the test procedure on a chip under test using a threshold derived from the baseline as a reference point to determine a stress history of the chip under test. The test procedure includes ordering each of a plurality of functional patterns by a respective minimum operating period corresponding thereto, ranking each pattern based on at least one preceding available pattern to provide a plurality of pattern ranks, and calculating a sum by summing the pattern ranks. The sum calculated by the ascertaining step is designated as the baseline, and the sum calculated by the repeating step is compared to the threshold to determine the stress history of the chip under test.