The Spoof: A New Technique for Analyzing the Effects of Faults on Logic Networks

摘要

In general, one cannot predict the effects of possible failures on the functional characteristics of a logic network without knowledge of the structure of that network. The SPOOF or structure-and-parity-observing output function described in this report provides a new and convenient means of characterizing both network structure and output function in a single algebraic expression. A straightforward method for the determination of a SPOOF for any logic network is demonstrated. Similarities between SPOOF's and other means of characterizing network structure are discussed. Examples are presented which illustrate the ease with which the effects of any 'stuck-at' fault--single or multiple-- on the functional characteristics of a logic network are determined using SPOOF's. It is also demonstrated how the SPOOF and other enumeration techniques which are developed may be used to establish upper bounds on, and in some cases exact counts of, the number of classes into which the faults which can occur in a network are partitioned by equivalence relations between these faults. (Author)