Counters Designs with Minimum Number of Cells and Area in the Quantum-Dot Cellular Automata Technology

The quantum-dot cellular automata (QCA) were highly regarded due to its high operating frequency and significantly low power consumption. One of the most useful circuits in processors architecture is counter. This paper presents effective designs and arrangement of QCA based counter-circuits. In this study new counter circuits in QCA technology are designed and precise simulation are done using the QCADesigner. Three, four and five bits counters are proposed in this paper in QCA technology. A comparison is made between the past and recent designs to illustrate which method is better and more efficient in terms of area, complexity, number of cells, and delay. For example, the proposed three bit shift register has 174 quantum cells, 0.2μm² occupied area and three QCA clock cycles delay.