Design and Analysis of Single layer QCA based 1- bit Comparators

Abstract

Quantum dot-cellular automata (QCA) technology is emerging as a potential candidate for the design of nanometer-scale computational circuits. In digital logic circuits, the comparator is the basic building block for comparing two binary values. This paper presents the design and implementation of two 1-bit QCA based comparators. The proposed QCA implementations are compact, require only a single layer and are therefore less complex compared to recent reported designs. The QCADesigner tool has been used to confirm the functional validity of the proposed QCA structures. The simulation results of the proposed comparators have shown considerable improvement compared to current comparators in terms of cell count, area, cost and efficient complexity. In addition, the proposed 1-bit comparator structures achieved a 25.8 % and 54.5% reduction in the number of cell requirements when compared to the best comparator designs. Moreover, both of the proposed structures achieve low cost and efficient complexity values relative to the recently reported structures. Moreover, all of the proposed structures are dissipating extremely low energy. Thus, proposed QCA based comparators can be viable option for low power digital applications.