Novel D Latches and D Flip-Flops with Set and Reset Ability in QCA Nanotechnology Using Minimum Cells and Area

Abstract

Emerging nanotechnology of Quantum-dot Cellular Automata (QCA) is one of the alternative technologies for CMOS technology. One of the essential parts of the structure of each arithmetic and logic units on the processors is the circuits that are affiliated with the Flip-Flops. Therefore, considering the importance of D Flip-Flops among different types of Flip-Flops and their more efficient performance, this paper presents new structures for D Latch and D Flip-Flops in QCA nanotechnology. First, the proposed D latch in QCA technology which has only 19 cells and a delay of 0.75 cycles is reported and will be compared with previous works. The comparison shows that the proposed D latch has the fewer number of cells, smaller area, and less delay. Then there are some methods for converting proposed latch into Flip-Flops, and with the help of these, new proposed falling edge, rising edge and dual edge triggered D Flip-Flops are suggested. The proposed structures have been designed in one layer. In terms of occupied area, delay and number of cells, the proposed D Flip-Flops are superior to previous structures. At last, set and reset pins will be added to proposed designs, and this is another advantage of proposed circuits, which is rarely seen in previous structures.