Compressor trees for decimal partial product reduction

Abstract

Decimal multiplication has grown in interest due to the recent announcement of new IEEE 754R standards and the availability of high-speed decimal computation hardware. Prior research enabled partial products to be coded more efficiently for their use in radix 10 architectures. This paper clarifies previous techniques for partial product reduction using carry-save adders and presents a new 4:2 compressor structure. This new structure improves performance at the expense of more gates, however, regularity is introduced into the circuit to promote implementations in Very Large Scale Integration (VLSI) Designs. Results are presented and compared for several designs using a TSMC SCN6M $0.18 mu m feature size.