Patent ID: 7379127
Filing Date: 2008-05-27
Classification: G02F

Abstract:
1. An electrostatic discharge (ESD) protection circuit for a liquid crystal display having a signal line and a common electrode, comprising: a first thin film transistor (TFT) having a first source/drain electrode and a first drain/source electrode, wherein the first drain/source electrode and the first source/drain electrode are coupled to the signal line and the common electrode, respectively; a first diode having a first positive end and a first negative end, wherein the first negative end is coupled to the gate electrode of the first TFT, and the first positive end is coupled to the signal line; a second TFT, having a second source/drain electrode and a second drain/source electrode, wherein the second drain/source electrode and the second source/drain electrode are coupled to the signal line and the common electrode, respectively; and a second diode, having a second positive end and a second negative end, wherein the second negative end is coupled to the gate electrode of the second TFT, and the second positive end is coupled to the common electrode; wherein when a first electrostatic charge is generated on the signal line, the corresponding voltage of the first electrostatic charge enables the first diode to conduct, so that the first electrostatic charge is discharged to the common electrode through the first TFT, and when a second electrostatic charge is generated on the common electrode, the corresponding voltage of the second electrostatic charge enables the second diode to conduct, so that the second electrostatic charge is discharged to the signal line through the second TFT.