Level shifter embedded in drive circuits with amorphous silicon TFTs

A drive circuit embedded with a level shifter was fabricated with conventional a-Si:H thin-film transistor (TFT) process. Two cascaded bootstrapped inverters were fabricated for the level shifter. The proposed level shifter shifts an input signal to a high voltage, for example, from 5 to 30 V. The level shifter embedded driver with a-Si:H TFT operates well for the input 5-V start pulse and clocks, and the 4th output of the driver shows 30.3-V output. The level shifter is stable under operation even though there is a threshold voltage shift of a-Si:H TFT. The stability of the driver was also investigated.