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Self-Timed Carry-Lookahead Adders
July 2000 (vol. 49 no. 7)
pp. 659-672
ASCII Text
x 
 
Fu-Chiung Cheng, Stephen H. Unger, Michael Theobald, "Self-Timed Carry-Lookahead Adders," IEEE Transactions on Computers, vol. 49, no. 7, pp. 659-672, July, 2000.
 
 
BibTex
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@article{ 10.1109/12.863035,
author = {Fu-Chiung Cheng and Stephen H. Unger and Michael Theobald},
title = {Self-Timed Carry-Lookahead Adders},
journal ={IEEE Transactions on Computers},
volume = {49},
number = {7},
issn = {0018-9340},
year = {2000},
pages = {659-672},
doi = {http://doi.ieeecomputersociety.org/10.1109/12.863035},
publisher = {IEEE Computer Society},
address = {Los Alamitos, CA, USA},
}
 
 
RefWorks Procite/RefMan/Endnote
x 
 
TY - JOUR
JO - IEEE Transactions on Computers
TI - Self-Timed Carry-Lookahead Adders
IS - 7
SN - 0018-9340
SP659
EP672
EPD - 659-672
A1 - Fu-Chiung Cheng,
A1 - Stephen H. Unger,
A1 - Michael Theobald,
PY - 2000
KW - Self-timed circuits
KW - delay-insenstive circuits
KW - carry-lookahead adders
KW - tree iterative circuits
KW - CMOS.
VL - 49
JA - IEEE Transactions on Computers
ER -
 

Abstract—Integer addition is one of the most important operations in digital computer systems because the performance of processors is significantly influenced by the speed of their adders. This paper proposes a self-timed carry-lookahead adder in which the logic complexity is a linear function of $n$, the number of inputs, and the average computation time is proportional to the logarithm of the logarithm of $n$. To the best of our knowledge, our adder has the best area-time efficiency which is $\Theta(n\log\log n)$. An economic implementation of this adder in CMOS technology is also presented. SPICE simulation results show that, based on random inputs, our 32-bit self-timed carry-lookahead adder is 2.39 and 1.42 times faster than its synchronous counterpart and self-timed ripple-carry adder, respectively; and, based on statistical data gathered from a 32-bit ARM simulator, it is 1.99 and 1.83 times faster than its synchronous counterpart and self-timed ripple-carry adder, respectively.

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Index Terms:
Self-timed circuits, delay-insenstive circuits, carry-lookahead adders, tree iterative circuits, CMOS.
Citation:
Fu-Chiung Cheng, Stephen H. Unger, Michael Theobald, "Self-Timed Carry-Lookahead Adders," IEEE Transactions on Computers, vol. 49, no. 7, pp. 659-672, July 2000, doi:10.1109/12.863035
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