Abstract: A fault simulator includes a circuit identifying section that selects, as fault generation points, circuit components subjected to a simulation from timing simulation results obtained by a static timing simulation of an LSI circuit; a fault value computing section that generates delay faults corresponding to the fault generation points using information about delay time and timing of signal transmission in the timing simulation result; and a fault simulating section that performs, by using a test pattern of the simulation, a logic simulation of a normal circuit of the LSI circuit and that of a faulty circuit where the delay faults are inserted into the fault generation points, and verifies detectability of the delay faults by the test pattern from the compared results of both the logic simulations. The fault simulator can reduce the time of the fault simulation.

Abstract: A fault simulator includes a circuit identifying section that selects, as fault generation points, circuit components subjected to a simulation from timing simulation results obtained by a static timing simulation of an LSI circuit; a fault value computing section that generates delay faults corresponding to the fault generation points using information about delay time and timing of signal transmission in the timing simulation result; and a fault simulating section that performs, by using a test pattern of the simulation, a logic simulation of a normal circuit of the LSI circuit and that of a faulty circuit where the delay faults are inserted into the fault generation points, and verifies detectability of the delay faults by the test pattern from the compared results of both the logic simulations. The fault simulator can reduce the time of the fault simulation.

Abstract: A fault verification apparatus performs a logic simulation of a circuit having a normal delay and a logic simulation of a circuit in which delay is intentionally changed for a node and compares the simulation results at a specific time and checks whether or not a test pattern can detect a fault due to a delay abnormality. The apparatus performs the logic simulation by applying the test pattern to the normal circuit and a variety of fault types and compares the expected values obtained from the results of the respective logic simulations and verifies whether or not the test pattern can detect the delay fault by whether or not the expected values are different from each other at a specific comparison point.