Addition of redundant Binary Signed Digits using RBSD adder

Adders are the basic and very important element of any arithmetic unit, especially fast parallel adder. Redundant Binary Signed Digit (RBSD) adders are designed to perform high-speed arithmetic operations. The RBSD Number System is gives the idea of carry free addition which reduces the addition time of two binary numbers. In computational environment manual computations is not convenient but useful in designing high-speed arithmetic machines. The main focus of this number system is that it eliminates the carry / borrows propagation chains which reduces the computational time and enhances the speed of the machine. In this paper description of different adders like Carry Save Addition, Wallace Tree Addition, Carry Select Adder are given and the circuit of fast RBSD adder cell is compared with Carry Look Ahead Adder.