Power Efficient and High-Accuracy Approximate Multiplier with Error Correction

Abstract

Approximate arithmetic circuits have been considered as an innovative circuit paradigm with improved performance for error-resilient applications which could tolerant certain loss of accuracy. In this paper, a novel approximate multiplier with a different scheme of partial product reduction is proposed. An analysis of accuracy (measured by error distance, pass rate and accuracy of amplitude) as well as circuit-based design metrics (power, delay and area, etc.) is utilized to assess the performance of the proposed approximate multiplier. Extensive simulation results show that the proposed design achieves a higher accuracy than the other approximate multipliers from the previous works. Moreover, the proposed design has a better performance under comprehensive comparisons taking both accuracy and circuit-related metrics into considerations. In addition, an error detection and correction (EDC) circuit is used to correct the approximate results to accurate results. Compared with the exact Wallace tree multiplier, the proposed approximate multiplier design with the error detection and correction circuit still has up to 15% and 10% saving for power and delay, respectively.