On optimality of adiabatic switching in MOS energy-recovery circuit

Abstract

The principle of adiabatic switching in conventional energy-recovery adiabatic circuit is generally explained with the help of a rudimentary RC circuit being driven by a constant current source. However, it is not strictly accurate to approximate a MOS adiabatic circuit by such an elementary model owing to its failure to incorporate the nonlinearity of very deep sub-micron transistors. This paper employs the theory of variational calculus in order to extend the principle of optimality used in this RC model to general MOS adiabatic circuits. Our experimental results include energy dissipation comparison in various adiabatic schemes using optimal power clocking versus other waveforms.