Automatic fault isolation techniques for digital systems

An automatic fault isolation technique to minimize fault isolation cost in digital systems is presented. Since the technique is implemented by additional hardware design instead of traditional software diagnostic procedures, the computation time and memory space required for fault isolation are eliminated. Two algorithms are developed, which specify the implementation of the design of the automatic fault isolation in terms of online or offline error detection, respectively. Based on the automatic fault isolation technique, highly available digital systems can be obtained since faults are isolated right after they are detected avoiding usual waiting time for fault isolation. Therefore, the recovery process can be executed as soon as possible. This technique has the ability to isolate intermittent faults while an online testing scheme is adopted in digital systems. The hardware overhead of the automatic fault isolation design is about 2% depending on digital system structures