Fredkin gate based energy efficient reversible D flip flop design in quantum dot cellular automata

Abstract

The latest developments in the electronics industry demands for ultra-low power dissipation circuit designing. Reversible logic, an emerging technology for designing digital circuits, is being investigated along with Quantum dot Cellular Automata (QCA) technology for designing high density and ultra-low power circuits in the sub-nano regime. Considering this, in this paper, a new and efficient design of 3x3 reversible Fredkin gate in QCA is proposed which utilizes only 48 cells. It is then used to design a new reversible logic based D Flip Flop. The proposed QCA circuit of reversible D Flip Flop is designed using only 59 cells. From the performance evaluation, it is seen that the proposed reversible logic based D Flip Flop achieves performance improvement of 41% percent in terms of cell count and cell area and 44% in terms of total area from the existing best design in the literature. In addition to this, proposed designs are more energy efficient hence making them more feasible and suitable for implementation in various ultra-low power applications.