A Novel Design of Self-Start Counter using Reversible Gates

When Moore’s law comes to the end, reversible logic is considered as the most promising technology to solve the problem of high power dissipation. Among the applications of reversible logic, quantum computing is one of the most significant issues in that the nature of quantum mechanics is reversible. Now many researchers concentrate their efforts on designing reversible circuits. One of the basic elements in the reversible sequential circuit is counter. In this paper, we proposed a novel design of a reversible counter whose chief characteristic is self-starting. Unlike other regular reversible counter designs, we fully consider the circumstance when reversible counter enters the invalid states, and we will make sure that the counter can still count even enters the invalid states. In addition, we also deal well with the irreversible problem brought by self-starting, and it should be noted that the design method of the self-start counter is different from the regular reversible counters which are just simply replaced with reversible gates directly. We presented a detailed analysis of a MOD-7 counter with self-starting character in this paper.