PROJECT TITLE :

Accurate QBF-Based Test Pattern Generation in Presence of Unknown Values

ABSTRACT:

Unknown (X) values emerge during the look process and throughout system operation and take a look at application. X-sources are for example black boxes in style models, clock-domain boundaries, analog-to-digital converters, or uncontrolled or uninitialized sequential parts. To compute a check pattern for a given fault, well-outlined logic values are required each for fault activation and propagation to observing outputs. In presence of X-values, standard test generation algorithms, primarily based on structural algorithms, Boolean satisfiability (SAT), or binary call diagram-based mostly reasoning might fail to come up with test patterns or to prove faults untestable. This paper proposes the primary efficient stuck-at and transition-delay fault check generation algorithm able to prove testability or untestability of faults in presence of X-values. It overcomes the principal pessimism of conventional algorithms when X-values are thought-about by mapping the test generation drawback to the SAT of quantified Boolean formulas. Experiments on ISCAS benchmarks and larger industrial circuits investigate the increase in fault coverage for standard deterministic and potential detection requirements for both randomized and clustered X-sources.