Cascaded carry-select adder (C/sup 2/SA): a new structure for low-power CSA design

In this paper we propose a novel low-power carry-select adder (CSA) design called cascaded CSA (C/sup 2/SA). Based on the prediction of the critical path delay of current operation, C/sup 2/SA can automatically work with one or two clock-cycle latency and a scaled supply voltage to achieve power improvement. Post-layout simulations of a 64-bit C/sup 2/SA in 180nm technology show that C/sup 2/SA can operate at a lower supply voltage, attaining 40.7% energy saving, while maintaining a similar (average) latency per operation (LPO) compared to standard CSA.