International Business Machines Corporation
Dynamic weight selection process for logic built-in self test

Abstract:

A series of pseudo-random test patterns provide inputs to a logic circuit for performing logic built-in self test (LBIST). A weight configuration module applies one or more weight sets to the pseudo-random test patterns, to generate a series of weighted pseudo-random test patterns. A logic analyzer determines a probability expression for each given net of the logic circuit, based on associated weight sets and a logic function performed by the net. A probability module computes an output probability for each net based on associated probability expressions and associated input probabilities. The weight configuration module optimizes the weight sets, based on the computed net probabilities, and further based on a target probability range bounded by lower and upper cutoff probabilities.