A single-supply sub-threshold level shifter with an internal supply feedback loop for multi-voltage applications

Abstract

A single-supply level shifter with an internal supply feedback loop, which can shift an input signal from the sub-threshold level to the above-threshold level, is presented in this paper. This level shifter has a wider voltage conversion, less transmission delay, higher energy efficiency, and more flexibility in the physical layout than those described in previous citations. The proposed level shifter can convert a 210-mV input signal into a 1.2-V output signal across process corners with a flexible physical layout when implemented in 65-nm LP technology. For a voltage of 0.2 V, the circuit has a propagation delay of 19.4 ns, a static power dissipation of 1.84 nW, and an energy consumption per transition of 82.2 fJ for a 1-MHz input signal. Due to these excellent characteristics, the proposed design is particularly suitable for applications in multi-voltage digital systems.