This paper proposes a novel design paradigm for circuits designed in quantum dot cellular automata (QCA) technology. Previously reported QCA circuits in the literature have generally been designed in a single layer ...This paper proposes a novel design paradigm for circuits designed in quantum dot cellular automata (QCA) technology. Previously reported QCA circuits in the literature have generally been designed in a single layer which is the main logical block in which the inverter and majority gate are on the base layer, except for the parts where multilayer wire crossing was used. In this paper the concept of multilayer wire crossing has been extended to design logic gates in multilayers. Using a 5-input majority gate in a multilayer, a 1-bit and 2-bit adder have been designed in the proposed multilayer gate design paradigm. A comparison has been made with some adders reported previously in the literature and it has been shown that circuits designed in the proposed design paradigm are much more efficient in terms of area, the requirement of QCA cells in the design and the input-output delay of the circuit. Over all, the availability of one additional spatial dimension makes the design process much more flexible and there is scope for the customizability of logic gate designs to make the circuit compact.展开更多
Quantum-dot cellular automata(QCA) is increasingly valued by researchers because of its nanoscale size and very low power consumption. However, in the manufacture of nanoscale devices prone to various forms of defects...Quantum-dot cellular automata(QCA) is increasingly valued by researchers because of its nanoscale size and very low power consumption. However, in the manufacture of nanoscale devices prone to various forms of defects, which will affect the subsequent circuits design. Therefore, fault-tolerant QCA architectures have become a new research direction. The purpose of this paper is to build a novel fault-tolerant three-input majority gate based on normal cells. Compared with the previous structures, the majority gate shows high fault tolerance under single-cell and double-cell omission defects. In order to examine the functionality of the proposed structure, some physical proofs under single cell missing defects are provided. Besides, two new fault-tolerant decoders are constructed based on the proposed majority gate. In order to fully demonstrate the performance of the proposed decoder, the previous decoders were thoroughly compared in terms of fault tolerance, area and delay. The result shows that the proposed design has a good fault tolerance characteristic, while the performance in other aspects is also quite good.展开更多
文摘Majority(MAJ)运算和反相(INV)运算组成完备集,数字逻辑电路可以用基于"MAJ/INV"的MI(Majority-Inverter)逻辑来实现。三输入MAJ门是MI逻辑电路的一种基本门电路单元。本文设计了一种基于碳纳米管场效应晶体管(Carbon Nanotube Field Effect Transistor,CNFET)的三输入MAJ门电路,并用所设计的MAJ门实现三个多输入组合逻辑电路。实验结果表明,在采用相同的器件和工艺的条件下,与现有的设计相比,所设计的MAJ门在功耗和功耗延时积上的改进最高分别达到32.5%和45.3%。
文摘This paper proposes a novel design paradigm for circuits designed in quantum dot cellular automata (QCA) technology. Previously reported QCA circuits in the literature have generally been designed in a single layer which is the main logical block in which the inverter and majority gate are on the base layer, except for the parts where multilayer wire crossing was used. In this paper the concept of multilayer wire crossing has been extended to design logic gates in multilayers. Using a 5-input majority gate in a multilayer, a 1-bit and 2-bit adder have been designed in the proposed multilayer gate design paradigm. A comparison has been made with some adders reported previously in the literature and it has been shown that circuits designed in the proposed design paradigm are much more efficient in terms of area, the requirement of QCA cells in the design and the input-output delay of the circuit. Over all, the availability of one additional spatial dimension makes the design process much more flexible and there is scope for the customizability of logic gate designs to make the circuit compact.
基金supported by the National Natural Science Foundation of China(No.61271122)
文摘Quantum-dot cellular automata(QCA) is increasingly valued by researchers because of its nanoscale size and very low power consumption. However, in the manufacture of nanoscale devices prone to various forms of defects, which will affect the subsequent circuits design. Therefore, fault-tolerant QCA architectures have become a new research direction. The purpose of this paper is to build a novel fault-tolerant three-input majority gate based on normal cells. Compared with the previous structures, the majority gate shows high fault tolerance under single-cell and double-cell omission defects. In order to examine the functionality of the proposed structure, some physical proofs under single cell missing defects are provided. Besides, two new fault-tolerant decoders are constructed based on the proposed majority gate. In order to fully demonstrate the performance of the proposed decoder, the previous decoders were thoroughly compared in terms of fault tolerance, area and delay. The result shows that the proposed design has a good fault tolerance characteristic, while the performance in other aspects is also quite good.