SIMPLE REALIZATION OF MULTI-BIT RIPPLE CARRY ADDERS IN QCA TECHNOLOGY

Abstract

An addition in digital signal processing is animportant constructional unit for making all arithmetic operations. A fulladder is a simple circuit that adds binary numbers. Ripple carry adder (RCA) isa cascade of the full adders that is used to add 8, 16, 32, etc. bit numbers.In this paper, multi-bit RCA is designed based on promising nanotechnologyQuantum-dot Cellular Automata (QCA). In fact, QCA is getting investigated as analternative to currently silicon-transistor based technology. The proposed RCAadder is designed as multilayer structure and is found as low complexity designin comparison with other RCA designs.