Pixel circuit of organic light-emitting display

摘要

A pixel of an OLED display is disclosed. A gate voltage of a driving transistor can be precisely adjusted using a second gate electrode that can supply DC power easily securing an operation range of an OLED. Further, by only adding one power line that can precisely adjust a gate voltage of a driving transistor to an OLED display, an operation range of the OLED can be easily secured and thus a drain current can be reduced without increasing a channel length of the driving transistor resulting in a narrower pixel area. According to various embodiments, the pixel can secure an operation range of the OLED by reducing a magnitude of a drain current by adjusting a gate voltage of a driving transistor.

主权项

1. An organic light-emitting diode (OLED) display, comprising:
a display unit comprising a plurality of pixels, wherein each of the pixels comprises at least one thin film transistor (TFT), at least one capacitor, and at least one OLED; a scan driver configured to transfer a plurality of scanning signals to the display unit; a light emission driver configured to transfer a plurality of light-emitting signals to the display unit; a data driver configured to transfer a plurality of data signals to the display unit; a DC power source unit configured to transfer direct current (DC) power to the display unit; and a controller configured to control the scan driver, the light emission driver, the data driver, and the DC power source unit, wherein the at least one TFT comprises a driving transistor configured to control a driving current flowing to the OLED, wherein the driving transistor comprises a first gate electrode formed over a first insulation layer and configured to receive a data voltage from the data driver and a second gate electrode configured to receive a DC voltage from the DC power source unit, wherein the OLED display further comprises a second insulation layer that is interposed between and in direct physical contact with the first and second gate electrodes, wherein a contact electrode is electrically connected to the first gate electrode, wherein the contact electrode is electrically insulated to the second gate electrode by a third insulation layer, wherein a first contact hole is formed in the second insulation layer, wherein a second contact hole is formed in the third insulation layer, and wherein a portion of the contact electrode is inserted into the first and second contact holes and is in direct physical contact with the first gate electrode.