An improved estimation methodology for hybrid BIST cost calculation

Abstract

This paper presents an improved estimation methodology for hybrid BIST cost calculation. In a hybrid BIST approach the test set is assembled from pseudorandom and deterministic test patterns. The efficiency of the hybrid BIST approach is largely determined by the ratio of those test patterns in the final test set. Unfortunately exact algorithms for finding the test sets are computationally very expensive. Therefore in this paper we propose an improved estimation methodology for fast calculation of the hybrid test set. The methodology is based on real fault simulation results and experimental results have shown that the method is more accurate than the statistical method proposed earlier.