Two Novel D-Flip Flops with Level Triggered Reset in Quantum Dot Cellular Automata Technology


1 Department of Electrical and Computer Engineering, University College of Rouzbahan, Sari, Iran.

2 Department of Engineering and Technology, University of Mazandaran, Babolsar, Iran


Quantum dot cellular automata (QCA) introduces a pioneer technology in nano scale computer architectures. Employing this technology is one of the solutions to decrease the size of circuits and reducing power dissipation. In this paper, two new optimized FlipFlops with reset input are proposed in quantum dot cellular automata technology. In addition, comparison with related works is performed.The reset pin in the proposed circuits is level triggered. Simulation results demonstrate that the both proposed desgins have efficient structures in terms of area, delay and complexity. The proposed structures are simulated using the QCADesigner and the validity of them has been proved. Simulations of the first proposed level triggered reset D-Flip Flop show that this circuit has 82 quantum cells and needs only two clock cycle for valid operation. In addition the second proposed architecture for level triggered reset D-Flip Flop has only 85 quantum cells and it needs only one clock cycle for proper operation.


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