Issue No. 06 - June (1980 vol. 29)
V.K. Agarwal , Department of Electrical Engineering, McGill University
The increasing recognition of PLA's as efficient and viable modules for such purposes as microprogramming and design of sequential controllers has led to a growing interest in the development of optimum fault detection test sets for these modules. It is now well known that a fault type which is unique to PLA's is the class of contact faults. A single contact fault is the spurious presence or absence of a contact between a row and a column of a PLA. We consider in this paper the problem of determining the capability of complete single contact fault test sets to cover multiple contact faults of PLA's. Our approach consists of developing a model of PLA's which allows one to represent a contact fault in a PLA as a stuck-at fault in the model of the PLA. Using this model, it is shown that more than 98 percent of all multiple contact faults of size 8 and less are inherently covered by every complete single contact fault test set in a PLA. Applications of this model to stuck-at fault diagnosis are also discussed.
single fault coverage, Contact faults, masking, multiple fault detection, PLA fault detection, PLA modeling, programmable logic arrays
V. Agarwal, "Multiple Fault Detection in Programmable Logic Arrays," in IEEE Transactions on Computers, vol. 29, no. , pp. 518-522, 1980.