Design and Optimization of Reversible BCD Adder/Subtractor Circuit for Quantum and Nanotechnology Based Systems

Abstract

Abstract: Reversible logic circuits have found emerging attention in nanotechnology, quantum computing and low power CMOS designs. In this paper we present a modular synthesis method to realize a reversible Binary Coded Decimal (BCD) adder/subtractor circuit. We use genetic algorithms and don’t care concept to design and optimize all parts of a BCD adder circuit in terms of number of garbage inputs/outputs and the quantum cost. We have also developed and used genetic algorithm-based synthesis software to design and optimize proper circuits for a reversible BCD adder/subtractor such as full adder, reversible 9’s complement generator and reversible multiplexer. The results show improvement in the quantum cost, the number of garbage inputs and outputs. Key words: Reversible logic circuits • Genetic algorithm • Synthesis of reversible circuits • Optimization • Don’t care • Reversible BCD adder, nanotechnology