Efficient testing of optimal time adders

Considers the design of two well-known optimal time adders: the carry look-ahead adder and the conditional sum adder. It is shown that 6 log/sub 2/(n)-4 and 6 log/sub 2/(n)+2 test patterns suffice to completely test the n-bit carry look-ahead adder and the n-bit conditional sum adder with respect to the single stuck-at fault model (for a given set of basic cells). The results are considered pertinent to establishing the correct behavior of a given VLSI chip.<
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