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

Abstract

The invention provides a pixel unit driving circuit and method, a pixel unit and a display device. The pixel unit driving circuit includes a driving thin film transistor, a matching thin film transistor, a signal clearing thin film transistor, a charging control unit, a driving control unit and a storage capacitor, the driving thin film transistor, the gate is connected to the first end of the storage capacitor and is connected to the driver through the charging control unit. Power connection, the source is connected to the driving power supply, the drain is connected to the OLED; the matching thin film transistor is connected to the data line through the charging control unit, the source is connected to the second end of the storage capacitor; the signal clearing thin film transistor is connected to the second end of the storage capacitor connection; the source of the signal clearing thin film transistor is connected with the gate and drain of the matching thin film transistor, and connected with the data line through the charging control unit. The invention can improve the brightness uniformity of the OLED panel.

Description

technical field [0001] The invention relates to the field of liquid crystal display, in particular to a pixel unit driving circuit and method, a pixel unit and a display device. Background technique [0002] The ability of AMOLED (Active Matrix Organic Light Emitting Diode) to emit light is driven by the current generated by the driving TFT in a saturated state, because when the same gray-scale voltage is input, different threshold voltages will produce different The drive current, resulting in current inconsistency. The uniformity of Vth (transistor threshold voltage) on the LTPS (low temperature polysilicon) process is very poor, and Vth also drifts, so the brightness uniformity of the traditional 2T1C pixel unit drive circuit has always been poor. [0003] The traditional 2T1C pixel unit driving circuit such as figure 1 As shown, the circuit only contains two TFTs, T1 is used as a switch, and DTFT is used for pixel driving. The operation of the traditional 2T1C pixel u...

AI Technical Summary

Problems solved by technology

The driving current formula of the 2T1C circuit includes Vth. As mentioned above, due to the immaturity of the LTPS process, even with the same process parameters, the Vth of the TFTs at different positions on the manufactured panel is quite different, resulting in the same gray area. The driving current of OLED is different under the step voltage, so the brightness of different positions of the panel under this driving scheme will be different, and the brightness uniformity is poor.

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