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In this paper, a hybrid 1-bit full adder design employing both complementary metal-oxide-semiconductor (CMOS) logic and transmission gate logic is reported. The design was first implemented for 1 bit and then extended for 32 bit also. The circuit was implemented using Cadence Virtuoso tools in 180-and 90-nm technology. Performance parameters such as power, delay, and layout area were compared with the existing designs such as complementary pass-transistor logic, transmission gate adder, transmission function adder, hybrid pass-logic with static CMOS output drive full adder, and so on. For 1.8-V supply at 180-nm technology, the average power consumption (4.1563 µW) was found to be extremely low with moderately low delay (224 ps) resulting from the deliberate incorporation of very weak CMOS inverters coupled with strong transmission gates. Corresponding values of the same were 1.17664 µW and 91.3 ps at 90-nm technology operating at 1.2-V supply voltage. The design was further extended for implementing 32-bit full adder also, and was found to be working efficiently with only 5.578-ns (2.45-ns) delay and 112.79-µW (53.36-µW) power at 180-nm (90-nm) technology for 1.8-V (1.2-V) supply voltage. In comparison with the existing full adder designs, the present implementation was found to offer significant improvement in terms of power and speed.Index Terms-Carry propagation adder, high speed, hybrid design, low power.

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We derive and solve the Boltzmann equation for viscosity and diffusive thermal conductivity at low temperatures in the B phase of superfluid 'He. The viscosity g is shown to tend towards a constant value as the temperature tends to zero, with the constant being inversely proportional to an angular average of the collision probability. A general expression for the collision probability valid at any temperature is given in terms of the singlet and triplet components of the normal-state scattering amplitude. If one takes for the normal-state amplitude the sand p-wave approximation, the constant viscosity is found to equal about one third of its value at the transition temperature. The diffusive thermal conductivity v~is found to vary as T ', as in the normal state, and with roughly the same coefficient of proportionality. We calculate as a function of pressure the viscosity and diffusive thermal conductivity in the normal state and in the superfluid at T = 0, and the normal-state quasiparticle relaxation time at the Fermi energy. The results are compared with experimental data, and the adequacy of the sand p-wave approximation for the normal-state scattering amplitude is discussed. Finite temperature corrections to g and~DT are obtained for a particularly simple normal-state scattering amplitude, showing that q initially decreases with increasing temperature while~~T increases.

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