International Conference on Computing, Communication and Automation

Reversible adder design for ripple carry and carry look ahead (4, 8, 16, 32-bit)

Somani Neelam, Chaudhary Chitrita, S. Ramani Yadav

Published Apr 1, 2016• 12 citations

Abstract

Reversible logic has represented itself as a prominent technology which plays an important role in Quantum Computing. Theoretically Quantum Computers operates at high speed and consumes less power. Furthermore, Reversible logic can break the conventional speed of power trade-off. To prove this we are implementing Ripple Carry Adder and Carry Look Ahead Adder using reversible logic gates. The paper presents efficient adder circuits using Peres gate, New fault Tolerant gate and Double Feyman gate. The complexity, simulated outputs and the speed parameters for the adder circuit have been indicated using the Quartus II 9.1 edition and Modelsim tool. Moreover, the quantum algorithms can potentially solve NP-complete problems. Furthermore, doing high performance functions beyond the limit of deterministic computer systems is possible by only reversible logic. Quantum operations are unitary in nature which is reversible and hence the arithmetic operations like adders can be implemented using the reversible logic. Likewise, optimized block size, minimum ancillary bits, and one to one mappings of inputs and outputs are obtained in the reversible adder circuit, giving fan out as 1. Hence, the Ripple Carry Adder and Carry look Ahead Adder is providing complexity reduction and high speed, proving to be an efficient and important part in the development of arithmetic blocks of Quantum Computers.

DOI: 10.1109/ccaa.2016.7813935

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