LAUSR

Quantum-dot cellular automata (QCA) technology for the next generation computers is capable of overcoming certain technical limitations of existing CMOS technology. We have first designed the Set–Reset (S–R) flipflop. But as S–R flipflop does not have a toggle output, it falls short of being adequate for designing three-bit and higher order Gray code counters. So we designed the J–K flipflop. These flipflops act as the basic building blocks of the Gray code counters. The designs of two-bit, three-bit and higher order Gray code counters are extensively studied and discussed. By computing the potential energies we have substantiated and analyzed the proposed design in terms of the energy and power related parameters. We have also compared our work with the existing two-bit counterpart using 4-dot 2-electron QCA cells and found that the proposed designs are superior to the existing ones in terms of space utilization, energy and power dissipation.