HyHOPE: fast fault simulator with efficient simulation of hypertrophic faults

In sequential circuit fault simulation, hypertrophic faults, which result from lengthened initialisation sequence in faulty circuits, usually produce a large number of fault events during simulation and require excessive gate evaluations. These faults degrade the performance of fault simulators attempting to simulate them exactly. In the paper, an exact simulation algorithm is developed to identify hypertrophic faults and to minimise their effects during fault simulation. The simulator HyHOPE, based on this algorithm, shows that the average speed-up ratio over HOPE for test vectors generated by STG3 is 1.65. Furthermore, the results indicate that the performance of HyHOPE is close to the approximate simulator, in which hypertrophic faults are simply dropped when they become potentially detected