Zero aliasing compression based on groups of weakly independent outputs in circuits with high complexity for two fault models

Abstract

The goal of the presentation is the development of a suboptimal procedure for the solution of a high complexity problem, namely the minimal selection of the groups of weakly independent outputs for large combinational circuits. The knowledge about the groups of weakly independent outputs is usable to reduce both the necessary number of output check bits for the built-in self-test in the average more than 80% with respect to the zero aliasing and the gate area of a self-testing error detecting circuit. It is demonstrated the deductive relationship between the weak independence and the partially self-checking property of the accompanying subcircuit and the relationship between the partially selfchecking property and the groupability property. For the test of this structurally realized functional property in a circuit graph, reduction operations and distance operators for a given circuit graph were used. The results for stuck-at and stuck-open faults are discussed by means of the combinational ISCAS 85 benchmarks.