Reduction of the energy consumption in adiabatic gates by optimal transistor sizing

Positive Feedback Adiabatic Logic (PFAL) with minimal dimensioned transistors can save energy compared to static CMOS up to an operating frequency f = 200MHz. In this work the impact of transistor sizing is discussed, and design rules are analytically derived and confirmed by simulations. The increase of the p-channel transistor width can significantly reduce the resistance of the charging path decreasing the energy dissipation of the PFAL inverter by a factor of 2. In more complex gates a further design rule for the sizing of the n-channel transistors is proposed. Simulations of a PFAL 1-bit full adder show that the energy consumption can be reduced by additional 10% and energy savings can be achieved beyond f = 1GHz in a 0.13μm CMOS technology. The results are validated through the use of the design centering tool 'WiCkeD' [1].