Table of Contents
VLSI Design
Volume 2018, Article ID 6153274, 13 pages
Research Article

First Steps in Creating Online Testable Reversible Sequential Circuits

1Department of Computer Science and Engineering, East West University, Aftabnagar, Dhaka 1212, Bangladesh
2Department of Mathematics and Computer Science, University of Lethbridge, Lethbridge, AB, Canada T1K 3M4

Correspondence should be addressed to Jacqueline E. Rice; ac.htelu@ecir.j

Received 2 May 2017; Accepted 6 December 2017; Published 14 January 2018

Academic Editor: Marcelo Lubaszewski

Copyright © 2018 Mozammel H. A. Khan and Jacqueline E. Rice. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Synthesis of reversible sequential circuits is a very new research area. It has been shown that such circuits can be implemented using quantum dot cellular automata. Other work has used traditional designs for sequential circuits and replaced the flip-flops and the gates with their reversible counterparts. Our earlier work uses a direct feedback method without any flip-flops, improving upon the replacement technique in both quantum cost and ancilla inputs. We present here a further improved version of the direct feedback method. Design examples show that the proposed method produces better results than our earlier method in terms of both quantum cost and ancilla inputs. We also propose the first technique for online testing of single line faults in sequential reversible circuits.