Peking University

Chuanli Leng

Shengdong Zhang

Congwei Liao

Zhijin Hu

Cuicui Wang

Longyan Wang

Xingwu Lin

Xue Meng

Provided is a pixel circuit. The pixel circuit comprises a driving transistor and a light-emitting element both coupled in series between a first level end and a second level end, and comprises a second transistor, a third transistor, a fourth transistor, a first capacitor and a second capacitor. The second capacitor is coupled between a control electrode of the driving transistor and a second end of the light-emitting element. A threshold voltage is stored by the first capacitor, so that threshold voltage compensation for the driving transistor and the light-emitting element is implemented, and therefore the non-uniformity of the display of the pixel circuit is compensated. Also provided is a display device, wherein a first control line and a light-emitting control line are both global lines. Also disclosed is a pixel circuit driving method.

Pixel circuit with compensation for drift of threshold voltage of OLED, driving method thereof, and display device

The present application discloses a low-voltage digital to analog conversion circuit, a data driving circuit and a display system. At least one voltage dividing unit comprises a number of resistors connected in series between a lower limit of voltage and an upper limit of voltage, and voltage dividing output terminals drawn from the resistors' connection nodes and an upper limit of voltage connection end. Introducing the voltage dividing unit renders the low-voltage digital signal to analog signal conversion circuit, the data driving circuit, and the display system low-voltage devices with low power consumption and small chip area.

Low-voltage digital to analog signal conversion circuit, data driving circuit and display system

The present application provides a gate driver circuit comprising at least one cascaded gate driver circuit unit. The low-level-holding enabling terminal of the gate driver circuit unit is connected to an adaptive voltage generating module. The adaptive voltage generating module generates a self-compensating voltage according to its constant current source and transmits to the low-level-holding enabling terminal, so as to provide an effective voltage level to the low-level-holding enabling terminal. Because the threshold voltage shift caused by pulling-down transistors in the low-level-holding module is embodied at the low-level-holding enabling terminal, the adaptive voltage generating module generates a self-compensating voltage with its constant current source according to the threshold voltage to compensate the increase of the threshold voltage. As such, the overdrive voltage of the pulling-down the transistors keep constant which provides good pulling-down performance, and consequently the lifetime of the gate driver circuit is prolonged.

Gate driving circuit, unit thereof, and display device

A pixel circuit, a drive method based on the pixel circuit, and a display device. The pixel circuit comprises: a first capacitor (C), a second capacitor (C), a second transistor (T), a third transistor (T) and a light-emitting branch for being coupled between a first common electrode (VDD) and a second common electrode (VSS); wherein the light-emitting branch comprises a first transistor (T), a fourth transistor (T) and a light-emitting element (OLED) which are connected in series; a first electrode of the first transistor (T) is coupled to a second electrode of the fourth transistor (T), and a coupling node is a third node (C); and a control electrode of the fourth transistor (T) is used for inputting a second scanning control signal (V), and the fourth transistor (T) switches the ON/OFF state of the light-emitting branch in response to the second scanning control signal (V). At the programming stage, a threshold voltage of the first transistor (T) is input to a first node (A) through the third transistor (T) and is stored; and at the light-emitting stage, a light-emitting current for driving the light-emitting element (OLED) is generated according to information about a voltage difference across two ends of the first capacitor (C). The pixel circuit is used for compensating for the threshold voltage shift of the first transistor (T) and the light-emitting element (OLED).

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Guangdong, China

Chuanli Leng