Dynamic Fault Diagnosis of Combinational and Sequential Circuits on Reconfigurable Hardware

This article describes an emulation-based method for locating stuck-at faults in combinational and synchronous sequential circuits. The method is based on automatically designing a circuit which implements a closest-match fault location algorithm specialized for the circuit under diagnosis (CUD). This method allows designers to perform dynamic fault location of stuck-at faults in large circuits, and eliminates the need for large storage required by a software-based fault dictionary. In fact, the approach is a pure hardware solution to fault diagnosis. We demonstrate the feasibility of the method in terms of hardware resources and diagnosis time by experimenting with ISCAS85 and ISCAS89 circuits. The emulation-based diagnosis method speeds up the diagnosis process by an order of magnitude compared to the software-based fault diagnosis. This speedup is important, especially, when the on-line diagnosis of safety–critical systems is of concern.