Au Optronics Corporation

Man-Wen Shih

Chien-Chung Huang

Chien-Ya Lee

Hua-Gang Chang

Wei-Chu Hsu

Ya-Ling Chen

Ching-Kai Lo

A shift register includes a plurality of shift register circuits. Each of the shift register circuits includes a first switch, an input circuit, a pull-down circuit and a ripple reduction circuit. The first switch is used to output a scanning signal of the shift register circuit according to voltage levels of a node and a clock signal. The input circuit is used to pull up the voltage level of the node according to a scanning signal of a previous shift register circuit. The pull-down circuit is used to pull down the voltage levels of the node and the scanning signal of the shift register circuit according to a scanning signal of a following shift register circuit. The ripple reduction circuit is used to suppress ripples on the voltage levels of the node and the scanning signal caused by the coupling effect of the clock signal.

Shift register

A pixel circuit includes four transistors, two capacitors and a light emitting element. A gate of first transistor receives a scan signal and a source/drain thereof receives a display data. A terminal of first capacitor couples to another source/drain of first transistor. A gate and a source/drain of second transistor couple to another terminal of first capacitor; and another source/drain thereof receives a switch signal. A terminal of second capacitor receives a reset signal; and another terminal thereof couples to another terminal of first capacitor. A gate of third transistor couples to a terminal of first capacitor. A gate of fourth transistor receives an enable signal; a source/drain thereof couples to a first power supply voltage; and another source/drain thereof couples to one source/drain of third transistor. The anode and cathode of the light emitting element couple to one source/drain of third transistor and a second power supply voltage, respectively.

Pixel circuit and display device using the same

Growing community of inventors

Hsin-Chu, Taiwan

Man-Wen Shih