Area Efficient Speculative Han-Carlson Adder

Authors(1) :-A. Dhanunjaya Reddy

Parallel prefix adders are used to compute the result with fixed delay and high speed. Better results can be produced by using speculation in these adders. Speculation is nothing but an approximation which can increase microprocessor clock frequency by modifying complete logic function with simplified one that speculates and observe the estimated outputs. This paper introduces a new variable delay speculative han-carlson adder which is combination of Brent-kung and Kogge-stone topologies that gives better performances compared to variable delay kogge-stone adder. Speculative han-carlson introduces error detection network which reduces the error occurences when speculation fails compared to former approaches. Both kogge-stone and han-carlson speculative adders are synthesized in the Xilinx tool which tells that speculative han-carlson adders have less area and more speed compared to speculative kogge-stone and kogge-stone respectively. And non-speculative adders give the best outputs when delay constraint is relaxed.

Authors and Affiliations

A. Dhanunjaya Reddy
PG scholar, JNTUA College of Engineering, Anantapuramu, Andhra Pradesh, India

Addition, parallel prefix adders, error detection network speculative adders, variable delay adders, digital arithmetic.

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Publication Details

Published in : Volume 3 | Issue 7 | September-October 2017
Date of Publication : 2017-10-31
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 119-127
Manuscript Number : IJSRST173740
Publisher : Technoscience Academy

Print ISSN : 2395-6011, Online ISSN : 2395-602X

Cite This Article :

A. Dhanunjaya Reddy, " Area Efficient Speculative Han-Carlson Adder", International Journal of Scientific Research in Science and Technology(IJSRST), Print ISSN : 2395-6011, Online ISSN : 2395-602X, Volume 3, Issue 7, pp.119-127, September-October-2017.
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