Pixel driving circuit and organic light-emitting diode (oled) display
AssigneeShenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd.
InventorsBobiao CHANG, Xiaolong CHEN, Yi-chien WEN, Ming-jong JOU
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Abstract
The present disclosure relates to a pixel driving circuit and an organic light-emitting diode (OLED) display having the pixel driving circuit. The pixel driving circuit adopts a 6T2C (six transistors and two capacitors) structure to compensate a threshold voltage of the driving thin film transistor (TFT) in the pixel. As such, a current passing through the OLED may not be related to the threshold voltage of the driving TFT. So as to eliminate the improper image-displaying of the OLED display resulting from the drifting of the threshold voltage of the driving TFT.
Claims12
A pixel driving circuit, comprising:
- a first thin film transistor (TFT), a second TFT, a third TFT, a fourth TFT, a fifth TFT, a sixth TFT, a first capacitor, a second capacitor, and an organic light-emitting diode (OLED);
- a gate of the first TFT electrically connecting to a first node, a source of the first TFT electrically connecting to a second node, and a drain of the first TFT electrically connecting to a third node;
- a gate of the second TFT being configured to receive emission controlling signals;
- a source of the second TFT being configured to receive initializing signals or data signals, and a drain of the second TFT electrically connecting to the second node;
- a gate of the third TFT being configured to receive the emission controlling signals, a source of the third TFT being configured to receive a positive voltage of a power supply, and a drain of the third TFT electrically connecting to the second node;
- a gate of the fourth TFT being configured to receive first scanning signals, a source of the fourth TFT electrically connecting to the third node, and a drain of the fourth TFT electrically connecting to the first node;
- a gate of the fifth TFT being configured to receive second scanning signals, a source of the fifth TFT electrically connecting to the second node, and a drain of the fifth TFT electrically connecting to the first node;
- a gate of the sixth TFT being configured to receive the emission controlling signals, a source of the sixth TFT electrically connecting to the third node, and a drain of the sixth TFT being configured to receive a negative voltage of the power supply;
- one end of the first capacitor electrically connecting to the first node, and the other end of the first capacitor electrically connecting to the second node;
- one end of the second capacitor electrically connecting to the first node, and other end of the second capacitor being grounded.
A pixel driving circuit, comprising:
- a potential initialization module, a threshold voltage storing module, an emission displaying module, and an OLED;
- the potential initialization module being configured to conduct a potential initializing operation according to emission signals and the second scanning signals at a low potential, and first scanning signals and initializing signals at a high potential during a potential initializing phase;
- the threshold voltage storing module being configured to conduct a threshold voltage storing operation according to the emission signals and the first scanning signals at the low potential, and the second scanning signals and the data signals at the high potential during a threshold voltage storing phase;
- the emission displaying module being configured to drive the OLED to illuminate according to the emission signals, the first scanning signals, and the second scanning signals at the high potential during an emission displaying phase;
- wherein a current driving the OLED to illuminate is not related to a threshold voltage of the emission displaying module.
Dependencies are inferred from the claim text.