Patent ID: 7138987
Filing Date: 2006-11-21
Classification: G02F,G09G,H01L

Abstract:
1. An input-output (I/O) protective circuit for use in a liquid crystal display having a I/O primary stage thin film transistor comprising: an I/O protective thin film transistor operatively coupled to the I/O primary stage thin film transistor and having a p-type substrate potential fixing terminal and an n-type substrate potential fixing terminal, both of which are operatively coupled to a channel layer of the I/O protective thin film transistor, wherein both p-type and n-type substrate potential fixing terminals are connected to a ground terminal, and wherein a breakdown voltage and a hold voltage of the I/O protective thin film transistor are made, respectively, lower than those of the I/O primary stage thin film transistor or those of a thin film transistor used as a switching element for driving a pixel of the liquid crystal display device.