Pixel unit drive circuit, pixel unit drive method, pixel unit and display device

Abstract

There are provided a pixel unit driving circuit and driving method, pixel unit and display apparatus. The pixel unit driving circuit is used for driving a light-emitting device to emit light, and comprises a first thin film transistor (T1), a second thin film transistor (T2), a third thin film transistor (T3) and a storage capacitor (Cs). A gate of the first thin film transistor (T1) is connected with a control line (Gate), a first electrode thereof is connected with a data line (Data), and a second electrode thereof is connected with a first node (A). One gate of the second thin film transistor (T2) is connected with the control line (Gate) and the other gate is connected with a second scan line (Scan2), a first electrode thereof is connected with the storage capacitor (Cs), and a second electrode thereof is connected with a second node (B). One gate of the third thin film transistor (T3) is connected with the first node (A) and the other gate is connected with the second scan line (Scan2), a first electrode thereof is connected with a power supply (Vdd), and a second electrode thereof is connected with the second node (B). One terminal of the storage capacitor is connected with the first node (A), and the other terminal is connected with the first electrode of the second thin film transistor (T2). One terminal of the light-emitting device is connected with the second node (B), and the other terminal thereof is grounded. The pixel unit driving circuit can reduce an influence on a driving voltage caused by variations in threshold voltage.

Description

technical field [0001] The present invention relates to the technical field of display driving, in particular to a pixel unit driving circuit, a pixel unit driving method, a pixel unit and a display device. Background technique [0002] OLED (Organic Light-Emitting Diode, organic light-emitting diode) display, also known as organic electroluminescence display, is an emerging flat-panel display device, due to its simple preparation process, low cost, low power consumption, high luminous brightness, Wide range of working temperature, light and thin size, fast response speed, easy to realize color display and large-screen display, easy to realize matching with integrated circuit driver, easy to realize flexible display, etc., so it has broad application prospects. [0003] OLED pixel units in organic electroluminescent displays are generally arranged in a matrix, and can be divided into passive matrix (Passive Matrix-Organic Light Emission Display, PM-OLED for short) driving me...

AI Technical Summary

Problems solved by technology

[0009] From the expression for the current through the OLED (i.e., Equation (1)), it can be seen that this current is not only affected by the data voltage V data controlled by the drive transistor T 2 Threshold voltage V th The impact, that is, the existing 2T1C structure cannot control the threshold voltage V th drift or threshold voltage V th Compensate for inconsistencies

Due to the driving transistor T in each pixel unit driving circuit 2 It is impossible to have completely consistent performance parameters, and there is no adjustment for the drive transistor T in the drive circuit of each pixel unit. 2 The threshold voltage of V th Compensation will inevitably cause inconsistent currents flowing through the OLEDs in each pixel unit, resulting in uneven luminance of each pixel unit, resulting in uneven brightness of the entire display screen and affecting the display effect; moreover, due to the current flowing through the OLEDs in each pixel unit current and data voltage V data It is a nonlinear relationship, so it is not conducive to the adjustment of the gray level of the entire display screen

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