5V input level shifter circuit for IGZO thin-film transistors

Abstract

A 5V input level shifter circuit based on depletion-mode In-Ga-Zn-O thin-film transistors (TFT) worked up to 100 kHz. By employing metal-insulator-semiconductor (MIS) active capacitor, we enhanced the bootstrapping effect and reduced the rise time of the output signal. SPICE simulation results showed that the proposed level shifter worked for wide threshold voltage range from ! 2V to D1V and the fabricated circuit exhibited the propagation delay t(plh) and t(phl) of 0.6 mu sec and 0.3 mu sec respectively.