An RT-level fault model with high gate level correlation

With the advent of new RT-level design and test flows, new tools are needed to migrate at the RT-level the activities of fault simulation testability analysis, and test pattern generation. This paper focuses on fault simulation at the RT-level, and aims at exploiting the capabilities of VHDL simulators to compute faulty responses. The simulator was implemented as a phototypical tool, and experimental results show that simulation of a faulty circuit is no more costly than simulation of the original circuit. The reliability of the fault coverage figures computed at the RT-level is increased thanks to an analysis of inherent VHDL redundancies, and by foreseeing classical synthesis optimizations. A set of "rules" is used to compute a fault list that exhibits good correlation with stuck-at faults.