Patent Number: 8,577,952

Title: Combined binary/decimal fixed-point multiplier and method

Abstract: A combined binary/decimal fixed-point multiplier that uses BCD-4221 recoding for the decimal digits. This allows the use of binary carry-save hardware to perform decimal addition with a small correction. The described designs provide an improved reduction tree organization to reduce the area and delay of the multiplier and improved reduction tree components that leverage the redundant decimal encodings to help reduce delay. A split reduction tree architecture is also introduced that reduces the delay of the binary product with only a small increase in total area. Area and delay estimates are presented that show that the proposed designs have significant area improvements over separate binary and decimal multipliers while still maintaining similar latencies for both decimal and binary operations.

Inventors: Erle; Mark Alan (Macungie, PA), Hickmann; Brian John (Hillsboro, OR)

Assignee: International Business Machines Corporation

International Classification: G06F 7/492 (20060101)

Expiration Date: 1/05/12017