An AMOLED Panel Test System Using Universal Data Driver ICs for Various Pixel Structures

Abstract

In this paper, we propose a test system for active-matrix organic light emitting diode (AMOLED) panels with various pixel structures with the external compensation method. The proposed AMOLED panel test system employs universal data drive ICs to measure the current of a driving thin-film transistor (TFT) and the anode voltage of the OLED in various pixels by only programming the field-programmable gate array in the proposed test system. The universal data driver IC are fabricated and implemented in the proposed AMOLED panel test system whose test board is assembled with a 55-in full-high-definition AMOLED panel. A fabricated universal data driver IC includes 640 data channels with a 12-b linear gamma digital-to-analog converter and 12-bit variable current sources. To evaluate the repeatability error of the proposed panel test system, the current of the driving TFT is repeatedly measured and the measured maximum repeatability error is 9.8 nA. In addition, to evaluate the measurement accuracy of the proposed panel test system, the variation in the currents of the driving TFTs is measured and compensated for, and its maximum value after compensation is 26 nA.