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A Recursive Carry-Lookahead/Carry-Select Hybrid Adder
December 1993 (vol. 42 no. 12)
pp. 1495-1499

The author presents a very fast adder for double-precision mantissas, which is an improvement on T. Lynch and E. E. Swartzlandes, Jr.'s spanning tree carry lookahead adder or redundant cell adder which was implemented using the Am29050 microprocessor. The adder presented is faster than theirs mainly because Manchester carry chains of various lengths are used instead of chains all of the same length.

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Index Terms:
adders; delays; recursive carry-lookahead/carry-select hybrid adder; double-precision mantissas; spanning tree carry lookahead adder; redundant cell adder; Am29050 microprocessor; Manchester carry chains.
Citation:
V. Kantabutra, "A Recursive Carry-Lookahead/Carry-Select Hybrid Adder," IEEE Transactions on Computers, vol. 42, no. 12, pp. 1495-1499, Dec. 1993, doi:10.1109/12.260639
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