High Speed Multiplier using High Accuracy Floating Point Logarithmic Number System

Authors

1 Department of Electronics and Communication Engineering, National Institute of Technology Meghalaya, Shillong, Meghalaya-793003, India

2 Department of Electronics and Communication Engineering, JIS College of Engineering. Kalyani, West Bengal-741235, India

3 Department of Electronics and Telecommunication Engineering, Bengal Engineering and Science University, Shibpur, Howrah-711103, India

Abstract

The ASIC implementation of the high speed multiplier using high accuracy floating point logarithmic number system is reported in this paper. Most popularly used techniques to compute logarithmic calculations for digital signal processors are lookup table based implementation, polynomial approximation, and Taylor series expansion. But, all of these techniques suffer from low accuracy due to choice of only lower order terms of the expanded series. In the present work, logarithmic conversion is implemented by floating point (IEEE-754 single precision) converting methodology thereby eliminate series expansion which eventually resulted in high accuracy. The improvement in speed, by avoidance of carry propagation, was achieved through canonical signed digit code (CSDC) implementation, while the high accuracy was achieved through an error minimization circuitry specially designed for this purpose. The functionality of these circuits was checked and performance parameters like propagation delay and dynamic power consumption were calculated by spice spectre using 90nm CMOS technology. The propagation delay & power consumption of the resulting (128×128) bit multiplier (divider) was only ~93ns & ~80mW respectively for a layout area of ~25mm2. The implementation offered significant improvement in terms of accuracy, delay and power from earlier reported ones.

Keywords


Volume 21, Issue 3
Transactions on Computer Science & Engineering and Electrical Engineering (D)
June 2014
Pages 826-841
  • Receive Date: 15 October 2013
  • Revise Date: 22 December 2024
  • Accept Date: 27 July 2017