Patent ID: 6985003

Claim:
A testing circuit, integrated into a flat panel display comprising a plurality of pixels, a gate driving circuit, a data driving circuit, a plurality of scanning lines for selecting a desired pixel out of the pixels, and a plurality of data lines, for the interested pixel corresponding to the data line being tested by the testing circuit by setting the gate driving circuit to a first voltage level that biases the interested pixels to a positive voltage, and setting the gate driving circuit to a second voltage level in order to draw the desired pixels to ground, the testing circuit comprising: a comparator, having a first input terminal, a second input terminal, and an output terminal, for comparing a pixel voltage with a reference voltage so as to output a comparison signal via the output terminal, wherein the first input terminal receives the pixel voltage sent from the interested pixel as the gate driving circuit is set to the first voltage level, the second input terminal receives the reference voltage; and a registering circuit, being electrically coupled to the comparator, for receiving the comparison signal and generating a status signal according to the comparison signal so as to determine the performance of the interested pixel.