Analysis, Modeling and Optimization of Equal Segment Based Approximate Adders

Abstract

Over the past decade, several approximate adders have been proposed in the literature based on the design concept of Equal Segment Adder (ESA). In this approach, an N-bit adder is segmented into several smaller and independent equally sized accurate sub-adders. An N-bit ESA has two primary design parameters: (i) Segment size (k), which represents the maximum length of carry propagation; and (ii) Overlapping bits (l), which represents the minimum number of bits used in carry prediction, where 1 ≤ k < N and 0 ≤ l