Design of Novel Coplanar Counter Circuit in Quantum Dot Cellular Automata Technology

One of the emerging technology that can be used for replacing CMOS technology is Quantum-dot Cellular Automata (QCA) technology. Counter circuits are widely used circuits in the design of digital circuits. This paper presents and evaluates circuits for 2-, 3-, 4-, and 5-bit coplanar counter in the QCA technology. The designed QCA coplanar counter circuits are based on the modified D-Flip-Flop (D-FF) circuit that is designed in this paper. The designed QCA circuits are implemented and verified by using QCADesigner tool version 2.0.3. The results show that the designed circuits for 2-, 3-, 4-, and 5-bit coplanar counter contain 44 (0.03 μm²), 93 (0.07 μm²), 160 (0.13 μm²), and 245 (0.2 μm²) quantum cells (area). The comparison results indicate that the designed circuits have advantages compared to other QCA circuits in terms of cost, area, and cell count.