GOA circuit and liquid crystal display device
AssigneeShenzhen China Star Optoelectronics Technology Co., Ltd.
InventorWenying Li
Life of this patent
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Abstract
Disclosed are a GOA circuit and a liquid crystal display device. The GOA circuit includes multiple stages of GOA sub-circuits connected in cascade. In a pull-down unit of a GOA sub-circuit, a first thin film transistor and a second thin film transistor are connected in series. Leakage current at Q point in the GOA circuit can be reduced, stability of the GOA circuit can be improved in harsh environments, and reliability of a liquid crystal panel can be enhanced.
Claims16
A GOA circuit, comprising multiple stages of GOA sub-circuits connected in cascade, wherein each of the GOA sub-circuits comprises a pull-up control unit, a pull-up unit, a transfer unit, a pull-down unit, a pull-down holding unit, and a bootstrap unit,
- wherein the pull-up control unit is connected to a first signal input terminal, a second signal input terminal and a first node, and is configured to output a voltage signal of the second signal input terminal to the first node under control of the first signal input terminal;
- wherein the pull-up unit is connected to a high-frequency clock signal input terminal, a first signal output terminal and the first node, and is configured to input a clock signal of the high-frequency clock signal input terminal to the first signal output terminal,
- wherein the transfer unit is connected to the high-frequency clock signal input terminal, the first node and a second signal output terminal, and is configured to provide a voltage signal to a second signal input terminal of a GOA sub-circuit in another stage;
- wherein the pull-down holding unit is connected to the first node, a DC low-voltage input terminal, a first low-frequency clock signal input terminal, a second low-frequency clock signal input terminal and the first signal output terminal, and is configured to hold an output signal of the first signal output terminal at a low level;
- wherein the bootstrap unit is connected to the first node and the first signal output terminal, and is configured to raise a voltage at the first node;
- and
- wherein the pull-down unit comprises a first thin film transistor, a second thin film transistor, and a third thin film transistor,
- wherein a first pole, a second pole, and a gate of the first thin film transistor are connected to the first node, a first pole of the second thin film transistor, and a third signal input terminal respectively;
- wherein a second pole and a gate of the second thin film transistor are connected to the DC low-voltage input terminal and the third signal input terminal respectively;
- and
- wherein a first pole, a second pole, and a gate of the third thin film transistor are connected to the first signal output terminal, the DC low-voltage input terminal, and the third signal input terminal respectively;
- wherein the pull-down holding unit comprises a first pull-down holding circuit and a second pull-down holding circuit,
- wherein the first pull-down holding circuit is connected to the first node, the DC low-voltage input terminal, the first low-frequency clock signal input terminal and the first signal output terminal, and is configured to hold an output signal of the first signal output terminal at a low level;
- wherein the second pull-down holding circuit is connected to the first node, the DC low-voltage input terminal, the second low-frequency clock signal input terminal and the first signal output terminal, and is configured to hold the output signal of the first signal output terminal at a low level;
- wherein the first pull-down holding circuit comprises a sixth thin film transistor, a seventh thin film transistor, an eighth thin film transistor, a ninth thin film transistor, a tenth thin film transistor, an eleventh thin film transistor, and a twelfth thin film transistor,
- wherein a first pole, a second pole, and a gate of the sixth thin film transistor are connected to the first node, a first pole of the seventh thin film transistor, and a first pole of the eleventh thin film transistor respectively;
- wherein a second pole and a gate of the seventh thin film transistor are connected to the DC low-voltage input terminal and the first pole of the eleventh thin film transistor respectively;
- wherein a first pole, a second pole, and a gate of the eighth thin film transistor are connected to the first signal output terminal, the DC low-voltage input terminal, and the first pole of the eleventh thin film transistor respectively;
- wherein a first pole and a gate of the ninth thin film transistor both are connected to the first low-frequency clock signal input terminal, and a second pole thereof is connected to a first pole of the twelfth thin film transistor;
- wherein a first pole, a second pole, and a gate of the tenth thin film transistor are connected to the first low-frequency clock signal input terminal, the first pole of the eleventh thin film transistor, and the first pole of the twelfth thin film transistor respectively;
- wherein a second pole and a gate of the eleventh thin film transistor are connected to the DC low-voltage input terminal and the first node respectively;
- and
- wherein a second pole and a gate of the twelfth thin film transistor are connected to the DC low-voltage input terminal and the first node respectively.
A liquid crystal display device, comprising a GOA circuit, wherein the GOA circuit comprises multiple stages of GOA sub-circuits connected in cascade, and each of the GOA sub-circuits comprises a pull-up control unit, a pull-up unit, a transfer unit, a pull-down unit, a pull-down holding unit, and a bootstrap unit,
- wherein the pull-up control unit is connected to a first signal input terminal, a second signal input terminal and a first node, and is figured to output a voltage signal of the second signal input terminal to the first node under control of the first signal input terminal;
- wherein the pull-up unit is connected to a high-frequency clock signal input terminal, a first signal output terminal and the first node, and is configured to input a clock signal of the high-frequency clock signal input terminal to the first signal output terminal;
- wherein the transfer unit is connected to the high-frequency clock signal input terminal, the first node and a second signal output terminal, and is configured to provide a voltage signal to a second signal input terminal of a GOA sub-circuit in another stage;
- wherein the pull-down holding unit is connected to the first node, a DC low-voltage input terminal, a first low-frequency clock signal input terminal, a second low-frequency clock signal input terminal and the first signal output terminal, and is configured to hold an output signal of the first signal output terminal at a low level;
- wherein the bootstrap unit is connected to the first node and the first signal output terminal, and is configured to raise a voltage at the first node;
- and
- wherein the pull-down unit comprises a first thin film transistor, a second thin film transistor, and a third thin film transistor,
- wherein a first pole, a second pole, and a gate of the first thin film transistor are connected to the first node, a first pole of the second thin film transistor, and a third signal input terminal respectively;
- wherein a second pole and a gate of the second thin film transistor are connected to the DC low-voltage input terminal and the third signal input terminal respectively;
- and
- wherein a first pole, a second pole, and a gate of the third thin film transistor are connected to the first signal output terminal, the DC low-voltage input terminal, and the third signal input terminal respectively;
- wherein the pull-down holding unit comprises a first pull-down holding circuit and a second pull-down holding circuit,
- wherein the first pull-down holding circuit is connected to the first node, the DC low-voltage input terminal, the first low-frequency clock signal input terminal and the first signal output terminal, and is configured to maintain the output signal of the first signal output terminal at a low level;
- wherein the second pull-down holding circuit is connected to the first node, the DC low-voltage input terminal, the second low-frequency clock signal input terminal and the first signal output terminal, and is configured to hold the output signal of the first signal output terminal at a low level;
- wherein the first pull-down holding circuit comprises a sixth thin film transistor, a seventh thin film transistor, an eighth thin film transistor, a ninth thin film transistor, a tenth thin film transistor, an eleventh thin film transistor, and a twelfth thin film transistor,
- wherein a first pole, a second pole, and a gate of the sixth thin film transistor are connected to the first node, a first pole of the seventh thin film transistor, and a first pole of the eleventh thin film transistor respectively;
- wherein a second pole and a gate of the seventh thin film transistor are connected to the DC low-voltage input terminal and the first pole of the eleventh thin film transistor respectively;
- wherein a first pole, a second pole, and a gate of the eighth thin film transistor are connected to the first signal output terminal, the DC low-voltage input terminal, and the first pole of the eleventh thin film transistor respectively;
- wherein, a first pole and a gate of the ninth thin film transistor both are connected to the first low-frequency clock signal input terminal, and a second pole thereof is connected to a first pole of the twelfth thin film transistor;
- wherein a first pole, a second pole, and a gate of the tenth thin film transistor are connected to the first low-frequency clock signal input terminal, the first pole of the eleventh thin film transistor, and the first pole of the twelfth thin film transistor respectively;
- wherein a second pole and a gate of the eleventh thin film transistor are connected to the DC low-voltage input terminal and the first node respectively;
- and
- wherein a second pole and a gate of the twelfth thin film transistor are connected to the DC low-voltage input terminal and the first node respectively.
Dependencies are inferred from the claim text.