Implementation of Code Converters in QCAD

Quantum-dot Cellular Automata (QCA) is an leading technology for development of digital logic circuits in the field of nanotechnology, and is an potential alternative for designing high performance computers over existing transistor-based technology. The basic logic in QCA represents the binary state by polarization of electrons in quantum cells unlike the CMOS devices that represent logic levels using voltages. Clocking is used in QCA circuit to synchronize and control the information flow and to provide the power to run the circuit. One of the main differences between circuit design in QCA and in conventional CMOS technologies and devices is that QCA based circuit has no control over the clocks that is information is transmitted through each cell and not retained. Each cell erases its own state every cycle of the clock. Quantum cell is basic building block of QCA. These cells are used to design majority gate, using which all classical logic gates can be implemented. QCA Designer (QCAD) is software used for design and simulation of QCA-based circuits. In this paper, 3-bit binary-to-gray and 3-bit gray-to-binary code converters have been implemented using QCAD software.