Patent ID: 7180356
Filing Date: 2007-02-20
Classification: G09G,H03K

Abstract:
1. A level shift circuit formed with a thin-film transistor having a semiconductor layer composed of amorphous silicon having single channel polarity as a switching element, which transforms and outputs a first signal having a first voltage amplitude to a second signal having a second voltage amplitude larger than the first voltage amplitude comprising: an input stage inverter circuit for generating and outputting an inverted signal of the first signal and which has a first input terminal into which the first signal is inputted and a second input terminal into which a reversed phase signal of the first signal is inputted; an output stage inverter circuit which has a first input terminal into which a signal based on the first signal is inputted, a second input terminal into which the inverted signal is inputted, and an output terminal which generates and outputs the second signal; and a bootstrap circuit section comprising: (i) boosting means for boosting a voltage value of a signal voltage inputted into the first input terminal of the output stage inverter circuit which is set between the first input terminal and the output terminal of the output stage inverter circuit and which holds an electronic charge corresponding to a potential difference of the first signal and the second signal, and (ii) a switching element which prevents transport of the electric charge held in the boosting means while connecting a first end of a current path to the first input terminal of the input stage inverter circuit, inputting the first signal into a second end of the current path and impressing the first signal to the first input terminal of the output stage inverter circuit via the current path.