Fault covers in reconfigurable PLAs

Abstract

Three kinds of faults are considered: stuck-at faults, bridging faults, and crosspoint faults. A new way of repairing bridging faults is introduced. It is shown that the problem of finding a minimum cover is NP-complete but that a special case of this problem can be formulated as a 2-SAT problem, which can be solved in polynomial time. The problem of finding a feasible cover for RPLAs (reconfigurable programmable logic arrays) with bridging faults alone is shown to be NP-complete. A necessary and sufficient condition on the number of spares for the existence of a feasible cover and an algorithm for finding a minimum feasible cover are presented.<>