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Delay Optimization of Carry-Skip Adders and Block Carry-Lookahead Adders Using Multidimensional Dynamic Programming
August 1992 (vol. 41 no. 8)
pp. 920-930

The worst-case carry propagation delays in carry-skip adders and block carry-lookahead adders depend on how the full adders are grouped structurally together into blocks as well as the number of levels. The authors report on a multidimensional dynamic programming paradigm for configuring these two adders to attain minimum latency. Previous methods are applicable only to very limited delay models that do not guarantee a minimum latency configuration. Under the delay model, critical path delay is calculated not only taking into account the intrinsic gate delays, but also the fanin and fanout contributions.

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Index Terms:
delay optimisation; carry-skip adders; block carry-lookahead adders; multidimensional dynamic programming; worst-case carry propagation delays; minimum latency; critical path delay; gate delays; fanin; fanout; adders; carry logic; digital arithmetic; dynamic programming.
Citation:
P.K. Chan, M.D.F. Schlag, C.D. Thomborson, V.G. Oklobdzija, "Delay Optimization of Carry-Skip Adders and Block Carry-Lookahead Adders Using Multidimensional Dynamic Programming," IEEE Transactions on Computers, vol. 41, no. 8, pp. 920-930, Aug. 1992, doi:10.1109/12.156534
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