Design and Synthesis of a Carry-Free Signed-Digit Decimal Adder

The decimal arithmetic has been receiving an increased attention because of the growth of financial and scientific applications requiring high precision and increased computing power. This paper presents an efficient architecture for multi-digit decimal addition based on carry-free signed-digit numbers. In this study, the decimal adder architecture has been designed and synthesized using the TSMC 0.18mu technology. The synthesis results were compared to the existing decimal adders with respect to design area, delay and power consumption. These results show that proposed adder architecture improves the area-delay factor by 3 for a 32 digit adder.