Design of ternary reversible sequential circuits

A good number of efforts have been made on design of ternary reversible combinational circuits, but no significant attempt has yet been made to design arbitrary ternary reversible sequential circuits. In this paper, we have proposed a novel design method of ternary reversible sequential circuit using direct feedback of the present state output. We have also shown the way of making the circuit falling-edge triggered and pre-settable using Fredkin gate. For this purpose, for the first time, we have shown realization of Fredkin gate on the top of M-S gates. We have shown design examples of an arbitrary two-trit sequential circuit, three-trit up/down counter, and three-trit universal register.