A hybrid Ling carry-select adder

Hybrid adders, combining a sparse carry-lookahead tree and a carry-select output stage are a well-known implementation form of high-speed adders. In this paper, a hybrid Ling carry-select adder is presented. It is shown how a carry-select output stage can be used to eliminate the entire conversion of all pseudo-carries. The adder is implemented in enhanced multiple output domino logic (EMODL). A technique is presented to avoid false discharge paths, which present impairment to EMODL, in the sum selection multiplexer.