Pixel circuit, pixel driving method, display substrate and display device

Abstract

The invention provides a pixel circuit. The pixel circuit comprises a compensation circuit, a data write-in circuit, a light-emitting control circuit and a driving transistor, the compensation circuitis used for obtaining the threshold voltage of the driving transistor and the threshold voltage of the light-emitting device in the compensation stage, acquiring a data voltage provided by the data writing circuit in a writing stage, and outputting a control voltage to the first node according to the threshold voltage of the driving transistor, the threshold voltage of the light-emitting device,the data voltage and the voltage at the second node in the light-emitting stage, so that the driving current output by the driving transistor is irrelevant to the threshold voltage of the driving transistor and is in positive correlation with the threshold voltage of the light-emitting device, the data write-in circuit is used for writing data voltage provided by a data line into the compensationcircuit in a write-in stage; the light-emitting control circuit is used for enabling the second node and the third node to be disconnected in the compensation phase and the write-in phase and enablingthe second node and the third node to be connected in the light-emitting phase.

Description

technical field [0001] The invention relates to the display field, in particular to a pixel circuit, a pixel driving method, a display substrate and a display device. Background technique [0002] An active matrix organic light emitting diode panel (Active Matrix Organic Light Emitting Diode, AMOLED for short) is more and more widely used. The pixel light-emitting device of AMOLED is Organic Light-Emitting Diode (OLED for short), OLED can emit light because the driving transistor in the pixel circuit generates a driving current in a saturated state, and the driving current drives the OLED to emit light. [0003] However, in practical applications, it is found that the existing pixel circuits generally have the following two problems: [0004] First, in the existing low-temperature polysilicon process, the threshold voltage uniformity between the driving transistors on the display substrate is poor, and drift will occur during use, resulting in different pixel circuits recei...

AI Technical Summary

Problems solved by technology

[0004] First, in the existing low-temperature polysilicon process, the threshold voltage uniformity between the driving transistors on the display substrate is poor, and drift will occur during use, resulting in different pixel circuits receiving the same data. The driving current generated by different voltages is different, which leads to poor uniformity of OLED brightness;

[0005] Second, with the accumulation of OLED usage time, the threshold voltage of OLED increases, and the brightness of OLED light decreases

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