Improved synthesis of reversible sequential circuits

Synthesis of reversible sequential circuits is a very new research area. It has been shown that such circuits can be implemented using emerging technologies such as quantum dot cellular automata. Earlier work uses traditional designs for sequential circuits and replaces the flip-flops and the gates with their reversible counterparts. Our earlier work used a direct feedback method without any flip-flops, which proved to be better than the replacement technique in terms of both quantum cost and ancilla inputs. This work is an improved version of our direct feedback method, which uses a different approach to the reversible mapping of sequential circuits. Design examples show that the proposed method produces better results than our earlier method in terms of both quantum cost and ancilla inputs.