A Three-Transistor Pixel Circuit to Compensate for Threshold Voltage Variations of LTPS TFTs for AMOLED Displays

Author

Chih-Lung Lin ; Po-Syun Chen ; Mao-Hsun Cheng ; Yen-Ting Liu ; Fu-Hsing Chen

Author_Institution

Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan

Volume

11

Issue

2

fYear

2015

fDate

Feb. 2015

Firstpage

146

Lastpage

148

Abstract

This work presents a new pixel circuit adopting low-temperature polycrystalline-silicon thin-film transistors (LTPS TFTs) for active-matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit can compensate for the threshold voltage variations of the LTPS TFTs with a simple structure. Simulated results demonstrate that the OLED currents over the entire data voltage range are uniform for ±0.5 V variations in the threshold voltage of the driving TFT, unlike in a conventional circuit. Furthermore, the relative current error rates for parasitic loads in the 1280 ×720 resolution AMOLED display are less than 6%.

Keywords

LED displays; compensation; elemental semiconductors; organic light emitting diodes; silicon; thin film transistors; AMOLED displays; LTPS TFT; Si; active-matrix organic light-emitting diode displays; low-temperature polycrystalline-silicon thin-film transistors; parasitic loads; pixel circuit; relative current error rates; three-transistor pixel circuit; threshold voltage variations; Active matrix organic light emitting diodes; Capacitors; Error analysis; Thin film transistors; Threshold voltage; Active-matrix organic light-emitting diode (AMOLED); low-temperature polycrystalline-silicon (LTPS); thin-film transistor (TFT);

fLanguage

English

Journal_Title

Display Technology, Journal of

Publisher

ieee

ISSN

1551-319X

Type

jour

DOI

10.1109/JDT.2014.2383434

Filename

6990482