Improved 64-bit Radix-16 Booth Multiplier Based on Partial Product Array Height Reduction

Abstract

In this paper, we describe an optimization for binary radix-16 (modified) Booth recoded multipliers to reduce the maximum height of the partial product columns to [n/4] for n = 64-bit unsigned operands. This is in contrast to the conventional maximum height of [(n + 1)/4]. Therefore, a reduction of one unit in the maximum height is achieved. This reduction may add flexibility during the design of the pipelined multiplier to meet the design goals; it may allow further optimizations of the partial product array reduction stage in terms of area/delay/power and/or may allow additional addends to be included in the partial product array without increasing the delay. The method can be extended to Booth recoded radix-8 multipliers, signed multipliers, combined signed /unsigned multipliers, and other values of n.