A fast and area efficient complimentary pass-transistor logic carry-skip adder

A two-level carry-skip adder using complementary pass-transistor logic is presented in this paper. The proposed adder is fast, area efficient and highly modular. It is compared with a two-level carry-skip adder using CMOS logic, and with a carry-lookahead adder automatically generated with the ALLIANCE CAD tools. SPICE simulations of the circuit extracted from the layout are used to evaluate the adder delay, while switch-level simulations are used to evaluate average power dissipation.