Resolution of Diagnosis Based on Transition Faults

Abstract

The conventional detection conditions for transition faults do not predict fault effects that may be created when transition faults are activated and/or propagated by pulses (or hazards). For this, detection conditions that take hazards into consideration need to be used. However, since the occurrence of pulses cannot be predicted accurately based on a gatelevel circuit description, the transition fault model becomes more susceptible to pattern-dependent effects, where errors on observed outputs that are predicted by the fault model may not appear in a circuit-under-diagnosis. This paper considers the implications of these pattern-dependent effects on the resolution of fault diagnosis based on transition faults.

Static test compaction for transition faults under the hazard-based detection conditions

“…Similar conditions were also used for increasing the accuracy of defect diagnosis based on transition faults in [4]. The effects of using the hazardbased detection conditions on the resolution of fault diagnosis based on transition faults were discussed in [5].…”

“…As in [2]- [5], the proposed procedure does not rely on timing analysis to predict the occurrence of pulses since such analysis is complex and requires accurate circuit parameters that are not always available. Instead, it prefers to detect a fault under the conventional detection conditions whenever possible.…”