Nowadays, reversible logic is one of the most important issue which has emerged as a promising technology having its applications in low power CMOS, quantum computing, nanotechnology and optical computing. Reversible logic circuits give less power dissipation as well as distinct output that is assigned for each distinct input. The classical set of gates such as the NAND, AND, NOR, OR, XOR and XNOR are not reversible. Reversible circuits are like the conventional logic circuits except that they are built from reversible gates. In reversible gates, there is a unique, one-to-one mapping between the inputs and outputs, which differ from the conventional logic. One of the most important factors for the acceptance of reversible logic lies in the fact that it can give a logic design methodology to design ultra-low power application beyond KTln2 limit for those emerging nanotechnologies in which the energy dissipated due to information destruction will be a significant factor of the overall heat dissipation. In this paper represents the approaches to realize the Canonical Form of Boolean Expression (CFOBE) by using reversible COG gates . For this, two methods are proposed and a comparison is also made between these two methods in terms of the number of reversible gates, constant input, garbage output and total logical calculation.

Reversible Logic Reversible Gate Boolean algebra Canonical Boolean Expression Garbage Output Constant Inputs.