A novel approach to delay-fault diagnosis

The authors discuss possibilities of delay fault diagnosis based on fault simulation. They detail the proposed approach based on critical path tracing. A path tracing process is presented with information provided by a logic simulation. Due to the limitations induced by such a simulation, a reliable approach is described based on a six-valued logic simulation. It requires no delay size based fault models and considers only the fault-free circuit. This method is an alternative to fault simulation based approaches and provides perfectly reliable results. It does not require timing evaluations and can be very accurate