AMOLED pixel driving circuit and driving method, and display panel

Abstract

The invention provides an AMOLED pixel driving circuit and driving method, and a display panel. The AMOLED pixel driving circuit adopts a 7T1C structure, and has a reset phase, a data signal writing and threshold voltage compensation phase, and a light emission phase, which can compensate for threshold voltage drift of a first thin film transistor, that is, a driving thin film transistor; and in the light emitting phase, a connection path between a fourth thin film transistor in which the leakage occurs and a gate of the first thin film transistor, that is, the driving thin film transistor, isblocked by a second thin film transistor, which can reduce the gate potential drift of the driving thin film transistor due to leakage during the light emitting phase, and improve the AMOLED image quality.

Description

technical field [0001] The invention relates to the technical field of OLED display, in particular to an AMOLED pixel driving circuit, a driving method and a display panel. Background technique [0002] Organic Light Emitting Display (OLED) display panel has self-illumination, low driving voltage, high luminous efficiency, short response time, high definition and contrast, nearly 180° viewing angle, wide temperature range, and can realize flexible display With many advantages such as large-area full-color display, it is recognized by the industry as a display device with the most development potential. [0003] OLED can be divided into passive matrix OLED (Passive Matrix, PM) and active matrix OLED (Active Matrix, AM) according to the driving method, namely direct addressing and thin film transistor (Thin Film Transistor, TFT) matrix addressing. kind. [0004] The AMOLED display panel has a plurality of pixels arranged in an array, and each pixel is driven by an OLED pixel...

AI Technical Summary

Problems solved by technology

[0010] However, there is still an obvious deficiency in the existing AMOLED pixel driving circuit capable of compensating the threshold voltage of the driving thin film transistor: the source and drain of the thin film transistor used to reset the gate potential of the driving thin film transistor are directly electrically connected in the reset phase The gate of the driving thin film transistor is connected to a lower potential. In order to prevent the gate potential of the driving thin film transistor from drifting during the light emitting phase, the leakage current of the thin film transistor used to reset the gate potential of the driving thin film transistor in the reset phase must be very low. Small, but due to its large source-drain voltage, the thin-film transistor used to reset the gate potential of the driving thin-film transistor in the reset phase is more prone to leakage during the light-emitting phase, causing the gate potential of the driving thin-film transistor to drift, affecting the AMOLED image quality

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