Designing and Implementing a Fast and Robust Full-Adder in Quantum-Dot Cellular Automata (QCA) Technology

Moving towards nanometer scales, Quantum-dot Cellular Automata (QCA) technology emerged as a novel solution, which can be a suitable replacement for complementary metal-oxide-semiconductor (CMOS) technology. The 3-input majority function and inverter gate are fundamental gates in the QCA technology, which all logical functions are produced based on them. Like CMOS technology, making the basic computational element such as an adder with QCA technology, is considered as one of the most important issues that extensive research have been done about it. In this paper, a new QCA full-adder based on coupled majority-minority and 5-input majority gates is introduced which its novel structure, appropriate design technique selection and its arrangement make it very suitable. The experimental results showed that the proposed QCA full-adder makes only 48 cells and the first output is obtained in the 0.05clock. Therefore, the presented QCA full-adder improves the number of cells and gains a speedup rate of 33% in comparison with the best previous robust QCA full-adders. In addition, temperature analysis of the QCA full-adders shows that our design is more robust compared with other suggested QCA full-adders.