First Steps in Creating Online Testable Reversible Sequential Circuits

Table 6

Comparison of reversible realization of the four-bit falling-edge triggered universal register with that of the replacement design in [40] and the direct design in [26].

	Quantum cost	Ancilla input
Replacement design [40]	220	18
Direct design [26]	112	12
Present design	74	14
% improvement over replacement design [40]	66.36	22.22
% improvement over direct design [26]	33.93