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

Abstract

The invention provides a pixel unit drive circuit for driving a light-emitting device to emit light. A grid of a first thin film transistor is connected with a scanning line, a first pole is connected with a data line and a second pole is connected with a first node. One grid of a second thin film transistor is connected with a scanning line, the other grid is connected with a second control line, a first pole is connected with a storage capacitor, and a second pole is connected with a second node. One grid of the third thin film transistor is connected with the first node, the other grid is connected with the second control line, a first pole is connected with a power supply, and a second pole is connected with the second node. One end of the storage capacitor is connected with the first node. The other end of the storage capacitor is connected the first pole of the second thin film transistor. One end of the light-emitting device is connected with the second node. The other end of the light-emitting device is grounded. Correspondingly, a pixel unit drive method, a pixel unit and a display device are provided. By the pixel unit drive circuit, influence of variation of threshold voltage on drive voltage can be reduced even eliminated.

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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