Pixel compensating circuit

Abstract

The invention provides a pixel compensating circuit which comprises a first switch, a second switch, a third switch, a fourth switch, a fifth switch and an organic light-emitting diode, wherein a first end of the first switch is connected to a data signal; a control end of the first switch is connected to a scanning signal; a first end of the second switch is connected to reference voltage; a control end of the second switch is connected to a switching signal; a first end of the third switch is connected to first voltage; a control end of the third switch is connected to a first control signal; a first end of the fourth switch is connected to a second end of the third switch; a first end of the fifth switch is connected to a second end of the fourth switch; a control end of the fifth switch is connected to a second control signal; an anode of the organic light-emitting diode is connected to a second end of the fifth switch; and a cathode of the organic light-emitting diode is connected to second voltage. The pixel compensating circuit adopts the independent switching signal to complete write-in of the reference voltage and realizes data write-in by the complete scanning signal during a low level period, so that data pulses have adequate pulse widths to realize driving at a high frame speed, and the problem that the panel display is nonuniform is solved.

Description

technical field [0001] The invention relates to an active matrix organic light emitting diode panel, in particular to a pixel compensation circuit of the AMOLED panel. Background technique [0002] Organic light emitting diodes (Organic Light Emitting Diode, OLED) can be divided into passive matrix driving (Passive Matrix OLED, PMOLED) and active matrix driving (Active Matrix OLED, AMOLED) according to the driving method. Among them, the PMOLED does not emit light when data is not written, but only emits light during data writing. This driving method is simple in structure, low in cost, and easy to design, and is mainly suitable for small and medium-sized displays. [0003] The biggest difference between AMOLED and PMOLED is that each pixel has a capacitor to store data, so that each pixel can maintain a light-emitting state. Since the power consumption of AMOLED is significantly lower than that of PMOLED, and its driving method is suitable for the development of large-siz...

AI Technical Summary

Problems solved by technology

Considering that the OVDD metal line itself has impedance, there will be a voltage drop, resulting in a difference in the OVDD of each pixel, resulting in a current difference between different pixels

In this way, different currents flowing through the OLED will produce different brightness, and thus the AMOLED panel will be uneven.

In addition, due to the influence of the manufacturing process, the threshold voltages of the thin film transistors in each pixel are not the same. Even if the voltage Vdata of the same value is provided, the current generated by them will still be different, which will also cause uneven panels.

In addition, if a pixel compensation circuit is used to compensate the above voltage, most of the compensation circuits will be limited by the scan time being too short to affect the compensation effect.

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