Approaching the Design of Energy Recovery Logic Circuits Using TFETs

Reducing supply voltage is an effective way to reduce power consumption, however, it greatly reduces CMOS circuits speed. This translates in limitations on how low the supply voltage can be reduced in many applications due to frequency constraints. In particular, in the context of low voltage adiabatic circuits, another well-known technique to save power, it is not possible to obtain satisfactory power-speed trade-offs. Tunnel field-effect transistors (TFETs) have been shown to outperforms CMOS at low supply voltage in static logic implementations, operation due to their steep subthreshold slope (SS), and have potential for combining low voltage and adiabatic. To the best of our knowledge, the adiabatic circuit topologies reported with TFETs do not take into account the problems associated with their inverse current due to their intrinsic p-i-n diode. In this article, we propose a solution to this problem, demonstrating that the proposed modification allows to significantly improving the performance in terms of power/energy savings compared to the original ones, especially at medium and low frequencies. In addition, we have evaluated the relative advantages of the proposed TFET adiabatic circuits with respect to their static implementations, demonstrating that these are greater than for FinFET transistor designs.