Solid-State Electronics, Vol.64, No.1, 10-13, 2011
A novel 3-TFT voltage driving method of compensating V-TH shift for a-Si:H TFT and OLED degradation for AMOLED
This work demonstrates the feasibility of a novel pixel circuit by using three a-Si:H TFTs. The proposed circuit can stabilize the OLED current and provide an additional driving current to ameliorate the brightness degradation of the AMOLED. Measurement results indicate that the current degradation of the proposed circuit, caused by V-TH variations, is less than 5% over more than 50,000 s at 60 degrees C, whereas that of a conventional 2T1C pixel circuit is larger than 34%. Furthermore, to ameliorate the decrease in luminance owing to the OLED degradation, the OLED current can be increased by 10% by analyzing the current degradation and modulating the detected voltage appropriately. (C) 2011 Elsevier Ltd. All rights reserved.