Detection Test Set Research Articles

A Remark on the Nonminimality of Certain Multiple Fault Detection Algorithms

Poage has constructed a complex fault detection algorithm which generates a complete and minimal test set of all multiple stuck-at faults of a given combinational network. Several authors have derived from his method fast and simple multiple fault detection algorithms, which are claimed to generate complete test sets with a near-minimal or near-optimal number of tests. We show that the algorithms by Bossen and Hong and the algorithm by Yang and Yau may generate test sets with an exponential number of tests (relative to the number of inputs) where a linear number of tests is sufficient for a complete multiple fault detection test set.

Multiple Fault Detection in Programmable Logic Arrays

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.

Generic Fault Characterizations for Table Look-Up Coverage Bounding

Given any combinational, internal fan-out-free network and any complete single fault detection test set (SFDTS) for the network, we consider in this paper the problem of determining the minimal extent to which that SFDTS will cover multiple faults in the network. The basis of our approach is the development of a generic perspective to multiple faults which uses a representation of such faults called an L-expression. This perspective leads to a technique for obtaining the greatest lower bound on the multiple fault coverage capability of an SFDTS by means of a simple table look-up process. In addition to generalizing previously known results regarding multiple fault coverage, two particularly interesting results obtained from this approach are as follows: 1) On the average, every SFDTS for an internal fan-out-free network covers 92 percent of all multiple faults of sizes 8 and less. 2) On the average, every SFDTS for an internal fan-out-free network covers at least 46.1 percent of all multiple faults.

A realistic approach to detection test set generation for combinational logic circuits

A realistic approach to detection test set generation for combinational logic circuits

On the Design of Multiple Fault Diagnosable Networks

This paper considers the design of diagnosable combinational networks. The diagnosability criterion used here requires that the single fault detection test set for the network also detects all multiple faults. Several recent studies in the area of multiple fault diagnosis are reviewed and the results which are pertinent to this investigation are summarized. It is shown that, under certain conditions, internal fan-out may be present without adversely affecting the detection of multiple faults. These results suggest design techniques which lead to readily diagnosable networks.