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Minimum fault coverage in memory arrays: a fast algorithm and probabilistic analysis

Dept. of Inf. Syst. & Comput. Sci., Nat. Univ. of Singapore
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems (Impact Factor: 1.2). 07/1996; DOI: 10.1109/43.503937
Source: IEEE Xplore

ABSTRACT The problem of reconfiguring memory arrays using spare rows and
spare columns is known to be NP-complete and has received a great deal
of attention in recent years. For reason of cost effectiveness, it is
desirable in practice to find minimum reconfiguration solutions. While
numerous algorithms have been proposed to find minimum reconfiguration
solutions, they all run in worst case exponential time complexities. On
the other hand, existing heuristic algorithms with fast polynomial
running time cannot guarantee minimum solutions. This paper presents a
provably good heuristic algorithm for finding minimum reconfiguration
solution. Using random bipartite graphs, we prove that the
reconfiguration problem is almost always optimally solvable with our new
algorithm in polynomial time for all practical purposes. We also show
that our algorithm can be used to estimate the number of spare rows and
columns that are required to achieve a given percentage of yield for
RRAM's with known defect probabilities

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