Design of Low Power Combinational Circuits Using Reversible Logic and Realization in Quantum Cellular Automata

In modern VLSI systems, power dissipation is very high due to rapid switching of internal signals. Landauer showed that the circuits designed using irreversible elements dissipate heat due to the loss of information bits. Information is lost when the input vectors cannot be recovered from circuit’s output vectors. To overcome the above drawback reversible logic is introduced where the number of output vectors are equal to the number of input vectors. In this paper the basic reversible gates are realized using the tanner tool. The Half adder using CMOS logic is compared with the reversible logic and the corresponding power are measured using T-Spice. Keywords— Reversible Logic, Basic Reversible Gates, Power measurement The paper is organized as follows: the section one gives the overall introduction about the reversible logic. Section two gives information about the basic reversible logic gates. In the section three simulation of the half adder using CMOS logic and by using reversible logic is done using S-Edit. At last the power measured using CMOS logic is compared with the reversible logic and the corresponding results are elaborated.