Pixel circuit, organic electro-luminescent display apparatus using the pixel circuit and method of driving the apparatus

摘要

An organic electroluminescent display apparatus including a pixel circuit and a method of driving the organic electroluminescent display apparatus are provided. Embodiments of the present invention may solve problems where the luminance of light is changed due to a change of a voltage of an anode of an organic electro-light emitting device such that an image quality is deteriorated when N-type transistors are used to form the organic electroluminescent display apparatus.

主权项

1. A pixel circuit for driving a light emitting device comprising an anode electrode and a cathode electrode, the pixel circuit comprising:
a driving transistor comprising a first electrode and a second electrode for outputting a driving current according to a voltage applied to a gate electrode of the driving transistor; a second transistor for delivering a data signal to the gate electrode of the driving transistor in response to a scan control signal applied to a gate electrode of the second transistor; a third transistor for diode-connecting the driving transistor in response to the scan control signal applied to a gate electrode of the third transistor; a fourth transistor for applying an initialization voltage to the gate electrode of the driving transistor in response to an initialization control signal; a fifth transistor for applying a first power voltage to the second electrode of the driving transistor in response to an emission control signal; a sixth transistor directly electrically connected in series between the first electrode of the driving transistor and the anode electrode of the light emitting device for outputting the driving current output from the driving transistor to the anode electrode of the light emitting device in response to the emission control signal applied to a gate electrode of the sixth transistor; a seventh transistor for applying a reference voltage to the anode electrode of the light emitting device in response to the scan control signal applied to a gate electrode of the seventh transistor; and a capacitor comprising a first electrode and a second electrode, wherein the first electrode is directly electrically connected to the gate electrode of the driving transistor and the fourth transistor and wherein the second electrode is directly electrically connected to the anode electrode of the light emitting device and the seventh transistor, wherein the pixel circuit is configured such that the data signal is delivered to the gate electrode of the driving transistor through the second transistor, the driving transistor, and the third transistor, and wherein the driving transistor and the second, third, fourth, fifth, sixth, and seventh transistors are N-type transistors.