Designing High-Speed Adders in Power-Constrained Environments

Data-driven dynamic logic (D3L) is very efficient when low-power constraints are mandatory. Unfortunately, this advantage is typically obtained at the expense of speed performances. This paper presents a novel technique to realize D3L parallel prefix tree adders without significantly compromising speed performance. When applied to a 64-bit Kogge-Stone adder realized with 90-nm complementary metal-oxide-semiconductor (CMOS) technology, the proposed technique leads to an energy-delay product that is 29% and 21% lower than its standard domino logic and conventional D3L counterparts, respectively. It also shows a worst case delay that is 10% lower than that of the D3L approach and only 5% higher than that of the conventional domino logic.