Design and analysis of multiplier using approximate 4-2 compressor

Approximate computing has received significant attention as an attractive paradigm for error-tolerant applications to reduce the power consumption, delay and area with some trade-off in accuracy. This paper proposes the design of a novel approximate 4-2 compressor. A modified architecture of Dadda Multiplier is presented for the effective utilization of the proposed compressor and to reduce the error at the output. Through extensive experimental evaluation, the efficiency of the proposed compressor and multiplier are evaluated in a 45 nm standard CMOS technology and their parameters are compared with those of the state-of-the-art approximate multipliers. The results show that the proposed compressor accomplish a significant reduction in error rate compared to other approximate compressors available in the literature. In addition, the proposed multiplier shows 35%, 36% and 17% reduction in power consumption, delay and area respectively compared to those of exact multiplier. The effectiveness of multiplier is assessed by some of the image processing applications. On an average, the proposed multiplier processes images with 85% structural similarity compared to the exact output image. (C) 2019 Elsevier GmbH. All rights reserved.