An Energy-Efficient, Yet Highly-Accurate, Approximate Non-Iterative Divider

Abstract

In1 this paper, we present a highly accurate and energy efficient non-iterative divider, which uses multiplication as its main building block. In this structure, the division operation is performed by first reforming both dividend and divisor inputs, and then multiplying the rounded value of the scaled dividend by the reciprocal of the rounded value of the scaled divisor. Precisely, the interval representing the fractional value of the scaled divisor is partitioned into non-overlapping sub-intervals, and the reciprocal of the scaled divisor is then approximated with a linear function in each of these sub-intervals. The efficacy of the proposed divider structure is assessed by comparing its design parameters and accuracy with state-of-the-art, non-iterative approximate dividers as well as exact dividers in 45nm digital CMOS technology. Circuit simulation results show that the mean absolute relative error of the proposed structure for doing 1 32-bit division is less than 0.2%, while the proposed structure has significantly lower energy consumption than the exact divider. Finally, the effectiveness of the proposed divider in one image processing application is reported and discussed.