Magnetic QCA Majority Voter feasibility analysis

Among the “beyond CMOS” alternatives, Quantum dot Cellular Automata represents an innovative way to implement digital circuits. Particularly, the magnetic implementation (MQCA) favours the fabrication of circuits with a tiny power dissipation and with intrinsic memory capability. In this contribution we deeply analyse the key logic gate of MQCA circuits, the Majority Voter (MV), taking into account its physical feasibility and its consequent expected performance. Detailed simulations of the majority voter using a low level micromagnetic simulator, are reported. We have changed the distance among nanomagnets and their aspect ratio, to represent process variations. We have verified the range of operations of the gate and we have also performed a timing analysis. Results show how the delay of the gate changes if the distance between neighbour magnets is varied, demonstrating that the choice of the distance must be carefully done in order to balance the physical feasibility and the gate delay.