Patent ID: 8031155
Filing Date: 2011-10-04
Classification: G09G

Abstract:
1. A liquid crystal display device, comprising: a display unit having matrix type pixels defined by gate and data lines crossing with each other; a data driver to supply a data voltage to be supplied to the data lines via output lines, the output lines being less in number than the data lines; a plurality of signal input lines supplying a plurality of control signals that are sequentially shifted to a high state in one horizontal sync period during normal operations and a cutoff signal during testing operations; a plurality of demultiplexers supplying the data voltages of the output lines to one side of the data lines according to the plurality of control signals during the normal operations and cutting off the data lines from the output lines according to the cutoff signal during the testing operations; a data line check unit activated to directly supply a plurality of test data voltages to the other side of the data lines when the data driver is inactive; a single input terminal supplied with the cutoff signal to be inputted to the signal input lines to cut off the data lines from the output lines; and a switching unit commonly connecting the plurality of signal input lines to the single input terminal during the testing operations and commonly disconnecting the plurality of signal input lines from the single input terminal during the normal operations, according to an external control signal, wherein the single input terminal is further configured to send the cutoff signal to the switching unit along the same plurality of signal input lines while the plurality of control signals are at a low state, and wherein the plurality of demultiplexers are further configured to receive the cutoff signal to cut off the data voltage from the output lines.