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Quantum-dot Cellular Automata (QCA) circuits are very promising in term of technology and suitable replacement for CMOS circuits. The main building blocks for this technology are majority gate and inverter. Content Addressable Memory (CAM) is commonly used in applications that require high speed memory. In this paper, a novel five input majority gate is introduced, this gate is simulated with QCADesigner tool, and compared with previous same structures. Then, the proposed gate used to design CAM cell in a single layer after derive the minority gate from proposed majority gate. The proposed CAM design has a simple and robust structure and does not require wire crossover, also it reduces the complexity of the circuit compared to the existing structures

Quantum-dot Cellular Automata (QCA) is one of the most important computing technologies for the future and will be the alternative candidate for current CMOS technology. QCA is attracting a lot of researchers due to many features such as high speed, small size, and low power consumption. QCA has two main building blocks (majority gate and inverter) used for design any Boolean function. QCA also has an inherent capability that used to design many important gates such as XOR and Multiplexer in optimal form without following any Boolean function. This paper presents a novel design 2:1 QCA-Multiplexer in two forms. The proposed design is very simple, highly efficient and can be used to produce many logical functions. The proposed design output comes from the inherent capabilities of quantum technology. New 4:1 QCA-Multiplexer has been built using the proposed structure. The output waveforms showed the wonderful performance of the proposed design in terms of the number of cells, area, and latency

Quantum-dot Cellular Automata (QCA) is a new emerging technology for designing electronic circuits in nanoscale. QCA technology comes to overcome the CMOS limitation and to be a good alternative as it can work in ultra-high-speed. QCA brought researchers attention due to many features such as low power consumption, small feature size in addition to high frequency. Designing circuits in QCA technology with minimum costs such as cells count and the area is very important. This paper presents novel structures of D-latch and D-Flip Flop with the lower area and cell count. The proposed Flip-Flop has SET and RESET ability. The proposed latch and Flip-Flop have lower complexity compared with counterparts in terms of cell counts by 32% and 26% respectively. The proposed circuits are designed and simulated in QCADesigner software

Quantum-dot Cellular Automata (QCA) is a new technology for designing digital circuits in Nanoscale. This technology utilizes quantum dots rather than diodes and transistors. QCA supplies a new computation platform, where binary data can be represented by polarized cells, which can define by the electron’s configurations inside the cell. This paper explains QCA based combinational circuit design; such as half-adder and full-adder, by only one uniform layer of cells. The proposed design is accomplished using a novel XOR gate. The proposed XOR gate has a 50% speed improvement and 35% reduction in the number of cells needed over the best reported XOR. The results of QCADesigner software show that the proposed designs have less complexity and less power consumption than previous designs.

Transistor based CMOS technology has many drawbacks such as power consumption and cannot continue in following the scaling of Moore's law and system-on-a-chip in near future. These drawbacks lead the researchers to think about an alternative technology. Quantum-dot Cellular Automata (QCA) is a new nanoscale technology can implement the logical functionality by controlling the position of the electron. The basic building blocks for QCA circuit are majority gate and inverter, where AND and OR gate can be implemented using Majority gate by setting one of the inputs to "0" and "1" respectively. A lot of papers was introduced to propose a new gates construction such as XOR and 5- input majority gate in last few years. The complexity of the gate leads to the complexity of the whole circuit so whenever the proposed gate has a lower number of cells, that's mean it’s a better. In this paper, we introduce a new construction of a novel 5- input majority gate. QCADesigner tool will be used to show the simulation result of the proposed gate. Then we will compare the proposed gate with the most important previous counterpart gates

Quantum-dot Cellular Automata (QCA) is one of the most important discoveries that will be the successful alternative for CMOS technology in the near future. An important feature of this technique, which has attracted the attention of many researchers, is that it is characterized by its low energy consumption, high speed and small size compared with CMOS.  Inverter and majority gate are the basic building blocks for QCA circuits where it can design the most logical circuit using these gates with help of QCA wire. Due to the lack of availability of review papers, this paper will be a destination for many people who are interested in the QCA field and to know how it works and why it had taken lots of attention recently

The limitations of the Complementary Metal–Oxide–Semiconductor (CMOS) technology such as the dissipated power, hard lithography, and short channel efects, led the researchers to look for an alternative technology. The unique properties of the QCA technology such as low dissipated power, speed, and the small feature size were the reason for considering it as a CMOS alternative in this work. In this paper, a new layout for fve input single layer majority gate is proposed. The proposed majority gate is used in order to carry out new low power RAM cell with the ability to set the output or to reset it. Designing a cost efcient memory cell is an important issue because it is a brick unit for the whole RAM that considers the most essential component in the digital system. The proposed RAM cell shows improvement around 7% in terms of cost function and a noticeable reduction in switching energy. The QCADesigner tool is used in this work for circuit design and verifcation while the QCAPro tool is used for power analysis.

The quantum-dot cellular automata (QCA) nano-technique has attracted computer scientists due to its noticeable features such as low power consumption and small size. Many papers have been published in the literature about the utilization of this technology for de-signing many QCA circuits and for presenting logic gates in an optimal structure. The T flip-flop, which is an essential part of digital designs, can be used to design synchronous and asynchronous counters. This paper presents a novel T flip-flop structure in an optimal form. The presented novel gate was used to design an N-bit binary synchronous counter. The QCADesigner software was used to verify the designed circuits and to present the simulation results, while the QCAPro tool was used for the power analysis. The proposed design required minimal power and showed good improvements over previous designs.

Background/Objectives: Quantum-dot Cellular Automata (QCA) is a new nanoscale technology that is expected to be a persuasive replacement of CMOS technology. QCA technology competing for features concerning low power consumption, small physical size, and ultra-high speed. These features are beneficial for memory design. This study presents a new structure of the CAM cell in QCA technology. The presented cell is carried out in an optimal form by using a proposed unique block. Method: In this study, the QCADesigner tool was used for circuit design and the QCAPro tool was used for power analysis. Both of these tools were used in default parameters. Findings: It was found that the proposed CAM cell is less complexity and efficient in power consumption with improvements by 6%, 29% and 15% in terms of leakage, switching and total energy consumption. Improvement: The CAM cell is the main building block for the whole memory. So, the reduction in complexity and power consumption in the CAM cells is important to reach an optimal memory circuit.

Purpose Quantum-dot cellular automata (QCA) has attracted computer scientists as new emerging nanotechnology for replacement the current CMOS technology because it has unique characteristics such as high frequency, extremely small feature size and low power consumption. The main building blocks in QCA are the majority gate and inverter so any Boolean function can be represented using these gates. Many important circuits were the target for implemented in this technology in an optimal form, such as random-access memory (RAM) cell. QCA-RAM cells were introduced in literature with different forms but most of them are not optimized enough. This paper aims to demonstrate QCA inherent capabilities that can facilitate the design of many important gates such as the XOR gate and multiplexer (MUX) without following any Boolean function to get an optimum design in terms of complexity and delay.Design/methodology/approach In this paper, a novel structure of QCA-MUX in an optimal form will be used to design two unique structures of a RAM cell. The proposed RAM cells are the lowest cost required compared with different counterparts. The presented RAM cells used a new approach that follows the new suggested block diagram. The presented circuits are simulated and tested with QCADesigner and QCAPro tools.Findings The comparison of the proposed circuits with the previously reported in the literature show noticeable improvements in speed, area, and the number of cells. The cost function analysis results for the proposed RAM cells show significant improvement compared to older circuits.Originality/value A novel structure of QCA-MUX in an optimal form will be used to design two unique structures of a RAM cell.