Efficient design of dual‐mode nano counter: An approach using quantum dot cellular automata. (8th March 2022) - Khan, Angshuman
Abstract: Quantum dot Cellular Automata (QCA) is a promising paradigm after CMOS technology due to low power consumption and small area requirements. As the counter is the most important and fundamental component of the QCA sequential logic family, therefore current effort has been made to design and analysis a dual‐mode counter. The reported dual‐mode nano counter can be operated as a Ring counter (R‐counter) as well as it can be operated as a Twisted‐ring counter (T‐counter). To achieve this, two inverters, four majority voters, and four D flip‐flops have been fully utilized. The main advantage of this design is that a single nano‐counter circuit can perform both tasks of R‐counter and T‐counter, which therefore eliminates the design constraint of double QCA layouts. In addition to that, the proposed 4‐bit QCA layout is easily expandable to n ‐bit as per needs. With compared to the best‐reported design, the proposed dual‐mode counter has 75% and 29% less delay and cell count respectively. The area‐delay cost, QCA‐specific cost, and energy‐delay cost of the proposed circuit are approximately 13 times, 228 times, and 61 times superior to the previously reported best design. The designs were verified using the popular QCA layout design software QCADesigner 2.0.3. Simultaneously, two energy estimate tools, QCAPro and QCADesigner‐E (QDE), were utilized to investigate the circuits' energy dissipation.