Fast Adder Design using Redundant Binary Numbers with Reduced Chip Complexity

Abstract—Redundant Binary Signed Digit Adder and Multiplier circuits are logic circuits which are designed to perform high-speed arithmetic operations. Fast RBSD adder cell, proposed by Kal and Rajshekhar in 1990 was modified by Neelam Sharma in 2006 using universal logic. The proposed adder is re-modified for reducing the number of gates and thus the circuit complexity and cost. Further due to the reduced gate count, circuit area, number of levels and hence implementation time is reduced up to 1% as proved by VHDL synthesis report. Since multiplication is repetitive addition, the implementation time of the multiplier circuit will be reduced to a great extent. Thus the proposed RBSD adder cell using NOR and NAND gates will be a boost in the speed of sophisticated ALU Design of high speed machines.