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arXiv · 1901.09315

Asynchronous Early Output Block Carry Lookahead Adder with Improved Quality of Results

P Balasubramanian·D L Maskell·N E Mastorakis
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Abstract

A new asynchronous early output block carry lookahead adder (BCLA) incorporating redundant carries is proposed. Compared to the best of existing semi-custom asynchronous carry lookahead adders (CLAs) employing delay-insensitive data encoding and following a 4-phase handshaking, the proposed BCLA with redundant carries achieves 13% reduction in forward latency and 14.8% reduction in cycle time compared to the best of the existing CLAs featuring redundant carries with no area or power penalty. A hybrid variant involving a ripple carry adder (RCA) in the least significant stages i.e. BCLA-RCA is also considered that achieves a further 4% reduction in the forward latency and a 2.4% reduction in the cycle time compared to the proposed BCLA featuring redundant carries without area or power penalties.

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P Balasubramanian, D L Maskell, N E Mastorakis. 2019-01-27. Asynchronous Early Output Block Carry Lookahead Adder with Improved Quality of Results. https://arxiv.org/abs/1901.09315

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