Synthesis of Sequential Reversible Circuits through Finite State Machine

TL;DR

This paper proposes a novel method for synthesizing sequential reversible circuits from FSM descriptions, introducing low-cost reversible gates and optimized counter designs, advancing the development of reversible computing.

Contribution

It introduces a new reversible gate suitable for sequential circuits and a procedure to generate reversible circuits from FSM behavioral descriptions, improving optimization parameters.

Findings

Reversible counters with better gate counts and fewer garbage outputs.

A novel FSM-to-reversible circuit conversion procedure.

Enhanced optimization in reversible sequential circuit design.

Abstract

Reversible computing has attracted the attention of researchers due to its low power consumption and less heat dissipation compared to conventional computing. A number of reversible gates have been proposed by different researchers and various combinational circuits based on reversible gates have been developed. However the realization of sequential circuit in reversible logic is still at premature stage. Sequential circuits were not available because of feedback was not allowed in reversible circuit. However allowing feedback in space (not in time), some sequential reversible gates and circuits have been reported in the literature. In this dissertation, we have addressed the problem from two sides. One side is to propose a low cost reversible gate suitable for sequential building block i.e. T flip-flop and hence designing low cost synchronous and asynchronous counters. Another side is to generate the circuit from its behavioral description described in FSM form. Our propose designs of reversible counters are significantly better in optimization parameters such as gate counts, garbage outputs and constant inputs available in literature. We have also proposed a procedure for obtaining reversible circuit from behavioral description through FSM. A very few attempts have been reported in the literature for the conversion FSM to reversible FSM.Because of non-availability of generated sequential reversible circuit in literature, our results cannot be compared with any other circuits. We expect that the sequential reversible circuits will help in debugging the reversible circuits, handling the ambiguous state of an FSM and generating the original input in reverse direction by reversing the original output.