Liquid crystal display panel, driving circuit and manufacturing method of the same

Patent metadata

Field	Value
Publication number	US-10203574-B2
Application number	US-201514897624-A
Country	US
Kind code	B2
Filing date	Sep 24, 2015
Priority date	Sep 8, 2015
Publication date	Feb 12, 2019
Grant date	Feb 12, 2019

Abstract

A liquid crystal display panel and its driving circuit, manufacturing method are disclosed. The driving circuit has a first switching element. The first terminal of the first switching element is connected to one data line of the liquid crystal display panel. At the array manufacturing process stage, the control terminal of the first switching element is input a first reference voltage. The second terminal of the first switching element is connected to a first discharge circuit. During the stage to drive the liquid crystal display panel to display or to test the liquid crystal display panel, the control terminal of the first switching element is input a first control signal. The second terminal of the first switching element is input a data signal. By the aforementioned ways, it can simultaneously achieve an ESD protection and to save the panel space to be favorable for narrow frame design.

First claim

What is claimed is:

1. A driving circuit of an LCD panel, the LCD panel being a low temperature poly-silicon LCD panel, wherein the driving circuit comprises multiple first switching circuits;
each first switching circuit has a first switching element and a second switching element; the first switching element and the second switching element respectively have a control terminal, a first terminal and a second terminal; the first terminals of the first switching element and the second switching element are connected to the same data line of the LCD panel;
wherein at the array manufacturing process stage of the LCD panel, the control terminals of the first switching element and the second switching element are used respectively to be input by the first reference voltage and the second reference voltage; the second terminals of the first switching element and the second switching element are respectively connected to a first discharge circuit and a second discharge circuit; when the voltage of the data line is lower than the first reference voltage, the first switching element is turned on to discharge the voltage of the data line through the first discharge circuit; when the voltage of the data line is higher than the second reference voltage, the second switching element is turned on to discharge the voltage of the data line through the second discharge circuit; during the stage to drive the LCD panel to display or to test the LCD panel, the control terminal of at least one of the first switching element and the second switching element is input by a first control signal, and the second terminal of at least one of the first switching element and the second switching element is input by a data signal; thus, when the first control signal controls at least one of the first switching element and the second switching element to be turned on, the data signal passes through said switching element to be transmitted to the data line so that the LCD panel is achieved to display or to be tested.

2. The driving circuit according to claim 1 further comprising multiple second switching circuits, wherein
each second switching circuit has a third switching element and a fourth switching element; each second switching circuit corresponds to at least two of the first switching circuits; the second terminals of the first switching element of the at least two of the first switching circuits are connected to the first discharge circuit or to receive the data signal through the third switching element; the second terminals of the second switching element of the at least two of the first switching circuits are connected to the second discharge circuit or to receive the data signal through the fourth switching element; the third switching element and fourth switching element respectively have a control terminal, a first terminal and a second terminal; the first terminal of the third switching element is connected to the second terminals of the first switching elements of the corresponding at least two of the first switching circuits; the first terminal of the fourth switching element is connected to the second terminals of the second switching elements of the corresponding at least two of the first switching circuits;
at the array manufacturing process stage of the LCD panel, the control terminals of the third switching element and the fourth switching element are used respectively to be input by the first reference voltage and the second reference voltage; the first terminals of the third switching element and the fourth switching element are respectively connected to the first discharge circuit and the second discharge circuit; when the voltage of the data line connected by one of the corresponding first switching circuits is lower than the first reference voltage, the third switching element is turned on to discharge the voltage of the data line connected by the one of the corresponding first switching circuits through the first discharge circuit; when the voltage of the data line connected by one of the corresponding first switching circuits is higher than the second reference voltage, the fourth switching element is turned on to discharge the voltage of the data line connected by one of the corresponding first switching circuits through the second discharge circuit;
during the stage to drive the LCD panel to display or to test the LCD panel, the control terminal of at least one of the third switching element and the fourth switching element is input by a second control signal, and the second terminal of at least one of the third switching element and the fourth switching element is input by the data signal; the data signal is input to the second terminal of at least one of the first switching element and the second switching element of the at least two of the first switching circuits.

3. The driving circuit according to claim 2 , wherein the first reference voltage and the second voltage are ground voltage; the first discharge circuit and the second discharge circuit are short-circuit lines connected to the ground;
wherein at the array manufacturing process stage, the control terminals of the first switching elements, the second switching elements, the third switching elements and the fourth switching elements are all connected to the short-circuit lines; the first terminals of the third switching element and the fourth switching element of each second switching circuit are connected to the second terminals of the first switching elements and the second switching elements of the corresponding at least two of the first switching circuits; during the stage to drive the LCD panel to display or to test the LCD panel, the short-circuit lines are cut; then the first control signal is input to the control terminal of at least one of the first switching element and the second switching element of each first switching circuit; the second control signal is input to the control terminal of at least one of the third switching element and the fourth switching element of each second switching circuit; the data signal is input to the second terminal of at least one of the third switching element and the fourth switching element of each second switching circuit.

4. The driving circuit according to claim 3 , wherein the first switching elements and the third switching elements are N-type thin-film transistors; the second switching elements and the fourth switching elements are P-type thin-film transistors; the gate, source and drain are respectively regarded as the control terminal, the first terminal and the second terminal of each switching element.

5. An LCD panel comprising a driving circuit, wherein the driving circuit comprises multiple first switching circuits; each first switching circuit has a first switching element; the first switching element has a control terminal, a first terminal and a second terminal; the first terminal of the first switching element is connected to one data line of the LCD panel;
wherein at the array manufacturing process stage, the control terminal of the first switching element is used respectively to be input by the first reference voltage; the second terminal of the first switching element is connected to a first discharge circuit; when the voltage of the data line is higher than or lower than the first reference voltage, the first switching element is turned on to discharge the voltage of the data line through the first discharge circuit; during the stage to drive the LCD panel to display or to test the LCD panel, the control terminal of the first switching element is input by a first control signal, and the second terminal of the first switching element is input by a data signal; when the first control signal controls the first switching element to be turned on, the data signal passes through said first switching element to be transm

Assignees

• Shenzhen China Star Optoelect
• Wuhan China Star Optoelectronics Technology Co Ltd

Inventors

• Wang Cong
• Du Peng

Classifications

• G09G3/006

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title

• G09G2310/0297

  Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns · CPC title

• G09G3/3648 Primary

  using an active matrix (G09G3/367 - G09G3/3696 take precedence) · CPC title

• G02F1/136204 Primary

  Arrangements to prevent high voltage or static electricity failures · CPC title

• G02F1/1303

  Apparatus specially adapted to the manufacture of LCDs · CPC title