Pixel circuit of organic light-emitting display device and driving method thereof

Abstract

The invention provides a pixel circuit of an organic light-emitting display device. The pixel circuit comprises a first transistor, a second transistor, a feedback capacitor and an organic light-emitting element, wherein the first transistor is used for transmitting a high level to a first pole of the feedback capacitor in a first reset stage, and the second transistor is used for transmitting aninitial signal to a second pole of the feedback capacitor in the first reset stage; the first transistor is also used for transmitting a low level to the first pole of the feedback capacitor in the second reset stage; the second transistor is also used for closing the second pole of the feedback capacitor in the second reset stage to suspend the second pole of the feedback capacitor; wherein the second reset stage is after the first reset stage; and in the second reset stage, the potential variation of the first pole of the feedback capacitor is the difference between the high level and the low level, and the potential of the second pole of the feedback capacitor is obtained by subtracting the potential variation from the initial signal.

Description

technical field [0001] The present invention relates to an organic light-emitting display device, and more specifically, to a pixel circuit of a high-brightness and high-resolution organic light-emitting display and a driving method thereof. Background technique [0002] An Organic Light-Emitting Display (OLED) device is a display in which each organic light-emitting unit is driven to display an image by exciting an organic component with an electric current. figure 1 It is a schematic diagram of a pixel circuit of an organic light-emitting display device in the prior art, figure 2 for figure 1 Driving schematic diagram of the pixel circuit shown. Before the next frame signal is written into the pixel circuit, the anode signal of the organic light-emitting element must be reset to eliminate the signal voltage of the previous frame, so as to ensure that there is no deviation in loading the predetermined voltage. As shown in the figure, during the reset period of the reset...

AI Technical Summary

Problems solved by technology

When the cathode low potential -p1 is less than -2V or lower, the voltage difference between the gate and drain of the drive transistor M4 in the pixel circuit, the voltage difference between the gate and drain of the reset transistor M2, the gate of the reset transistor M2 The voltage difference between the source and the source will cause the transistor to break down due to the excessive instantaneous voltage, and the pixel circuit will fail

If the driving transistor M4 is set as an independent NMOS or an independent n-well (n well) PMOS, the risk of MV device breakdown will be reduced to a certain extent, but the independent n-well or NMOS will cause the size of the pixel circuit increases, resulting in a decrease in pixel resolution

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