Gate driving circuit, repairing method thereof and display device

Abstract

The application discloses a gate driving circuit, a repairing method thereof and a display device. The gate driving circuit comprises a plurality of gate driving units in cascade. The nth gate driving unit further comprises a repairing circuit. The repairing circuit comprises a first repairing unit and a second repairing unit. The first repairing unit is used for connecting a pull-down output end of a stage transmission unit of the nth gate driving unit with a pull-down output end of a stage transmission unit of an (n+1)th gate driving unit in a repairing process. The second repairing unit is used for connecting a pull-up output end of the stage transmission unit of the nth gate driving unit with a pull-up output end of the stage transmission unit of the (n+1)th gate driving unit in the repairing process, or connecting the pull-up output end of the stage transmission unit of the nth gate driving unit with a pull-up output end of a stage transmission unit of an (n-1)th gate driving unit. The gate driving circuit is repaired by the repairing circuit when a stage transmission signal fails.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a gate driving circuit, a repairing method thereof and a display device. BACKGROUND

[0002] Liquid crystal display is a technology using liquid crystal layer to control the propagation and blocking of light. The liquid crystal layer is located between two parallel glass substrates, and the arrangement of liquid crystal molecules is controlled by applying electric field, so as to realize the propagation or blocking of light. Liquid crystal display has low power consumption, high brightness and long service life. The GOA (Gate on Array) circuit is a very simplified gate driving circuit, which integrates the gate driving circuit on the array substrate of the display panel, thereby reducing the circuit required for binding. The GOA circuit adopts a time-division multiplexing-like manner to transmit the driving signal by row or by area, thereby realizing the driving and control of the entire panel.

[0003] Since the GOA circuit adopts the level transmission manner to transmit the driving signal by row or by area, it has the advantage of reducing the complexity of the circuit. However, when a level transmission signal fails, it may cause the entire GOA circuit to fail to operate normally. Therefore, the skilled in the art urgently needs a technical solution to solve the above problems. SUMMARY

[0004] The purpose of the present application is to provide a gate driving circuit, a repairing method thereof and a display device. By setting a repairing circuit, the gate driving circuit is repaired when a level transmission signal fails.

[0005] The application discloses a gate drive circuit, comprising a plurality of cascaded gate drive units for sequentially turning on scan lines; each gate drive unit comprises a pull-up unit, a stage transmission unit, a pull-down unit and an output unit, the pull-up unit of the nth gate drive unit is used for receiving a pull-up signal output by the stage transmission unit of the nth-k gate drive unit; the pull-down unit of the nth gate drive unit is used for receiving a pull-down signal output by the stage transmission unit of the nth+k gate drive unit; the pull-down output end of the stage transmission unit of the nth gate drive unit outputs a pull-down signal to the pull-down unit of the nth-k gate drive unit, and the pull-up output end of the stage transmission unit of the nth gate drive unit outputs a pull-up signal to the pull-up unit of the nth+k gate drive unit; the output unit of the nth gate drive unit outputs a scan signal to the nth scan line; wherein the nth gate drive unit further comprises a repair circuit, the repair circuit comprises a first repair unit and a second repair unit, the first repair unit is used for connecting the pull-down output end of the stage transmission unit of the nth gate drive unit and the pull-down output end of the stage transmission unit of the nth+1 gate drive unit in a repair process; the second repair unit is used for connecting the pull-up output end of the stage transmission unit of the nth gate drive unit and the pull-up output end of the stage transmission unit of the nth+1 gate drive unit in a repair process; or connecting the pull-up output end of the stage transmission unit of the nth gate drive unit and the pull-up output end of the stage transmission unit of the nth-1 gate drive unit; wherein n, n-k, n+k, n+1 and n-1 are integers greater than 0.

[0006] Optionally, the repair circuit further comprises a third repair unit, the second repair unit is used for connecting the pull-up output end of the stage transmission unit of the nth gate drive unit and the pull-up output end of the stage transmission unit of the nth-1 gate drive unit in a repair process; the third repair unit is used for connecting the pull-up output end of the stage transmission unit of the nth gate drive unit and the pull-up output end of the stage transmission unit of the nth+1 gate drive unit in a repair process; wherein when the stage transmission unit of the nth gate drive unit fails, the second repair unit and the third repair unit work respectively, so that the pull-up output end of the nth-1 gate drive unit and the pull-up output end of the nth+1 gate drive unit are connected to the pull-up output end of the nth gate drive unit, and the pull-up unit of the nth+k gate drive unit is provided with a pull-up signal.

[0007] Optionally, the first repair unit comprises a first repair line; the second repair unit comprises a second repair line, and the third repair unit comprises a third repair line; the first repair line is used to connect the pull-down output end of the stage transmission unit of the n-th gate drive unit with the pull-down output end of the stage transmission unit of the n+1-th gate drive unit in the repair process; the second repair line is used to connect the pull-up output end of the stage transmission unit of the n-th gate drive unit with the pull-up output end of the stage transmission unit of the n-1-th gate drive unit in the repair process; and the third repair line is used to connect the pull-up output end of the stage transmission unit of the n-th gate drive unit with the pull-up output end of the stage transmission unit of the n+1-th gate drive unit in the repair process.

[0008] Optionally, the first repair unit comprises a first active switch; the second repair unit comprises a second active switch, and the third repair unit comprises a third active switch; after the repair process of the stage transmission unit of the n-th gate drive unit, the input end and the control end of the first active switch are connected with the pull-down output end of the stage transmission unit of the n+1-th gate drive unit; the output end of the first active switch is connected with the pull-down output end of the stage transmission unit of the n-th gate drive unit; the input end and the control end of the second active switch are connected with the pull-up output end of the stage transmission unit of the n-1-th gate drive unit; the output end of the second active switch is connected with the pull-up output end of the stage transmission unit of the n-th gate drive unit; the input end and the control end of the third active switch are connected with the pull-up output end of the stage transmission unit of the n+1-th gate drive unit; and the output end of the third active switch is connected with the pull-up output end of the stage transmission unit of the n-th gate drive unit.

[0009] Optionally, the pull-up output end of the stage transmission unit of the nth stage of the gate drive unit is connected to the pull-up unit of the stage transmission unit of the nth+k stage of the gate drive unit through a pull-up wire, and the pull-down output end of the stage transmission unit of the nth stage of the gate drive unit is connected to the pull-down unit of the stage transmission unit of the nth-k stage of the gate drive unit through a pull-down wire; wherein the first cutting line is arranged on the side close to the gate drive unit of the pull-up wire, and the second cutting line is arranged on the side close to the gate drive unit of the pull-down wire; when the stage transmission unit of the nth stage of the gate drive unit fails, the first cutting line and the second cutting line at both ends of the stage transmission unit of the nth stage of the gate drive unit are cut; after the repair process of the stage transmission unit of the nth stage of the gate drive unit is performed, the input end and the control end of the first active switch are connected to the pull-down wire of the stage transmission unit of the nth+1 stage of the gate drive unit; the output end of the first active switch is connected to the pull-down wire of the stage transmission unit of the nth stage of the gate drive unit; the input end and the control end of the second active switch are connected to the pull-up wire of the stage transmission unit of the nth-1 stage of the gate drive unit; the output end of the second active switch is connected to the pull-up wire of the stage transmission unit of the nth stage of the gate drive unit; the input end and the control end of the third active switch are connected to the pull-up wire of the stage transmission unit of the nth+1 stage of the gate drive unit; and the output end of the third active switch is connected to the pull-up wire of the stage transmission unit of the nth stage of the gate drive unit.

[0010] Optionally, the gate drive circuit is arranged on the glass substrate, and the first repair unit, the second repair unit and the third repair unit are arranged in the same film layer; and the pull-up wire and the pull-down wire are arranged in the same film layer.

[0011] The application further discloses a repair method of a gate drive circuit, wherein the gate drive circuit is the above-mentioned gate drive circuit, and the repair method comprises the following steps: when flicker occurs in the row pixels of a display panel, determining the stage number of the gate drive units in the gate drive circuit according to the number of pixel rows; and when the nth stage of the gate drive units fails, repairing the nth stage of the gate drive units by using a repair process; wherein the repair process comprises the following steps: connecting the pull-down output end of the stage transmission unit of the nth stage of the gate drive units to the pull-down output end of the stage transmission unit of the nth+1 stage of the gate drive units by using the first repair unit; connecting the pull-up output end of the stage transmission unit of the nth stage of the gate drive units to the pull-up output end of the stage transmission unit of the nth+1 stage of the gate drive units by using the second repair unit; or connecting the pull-up output end of the stage transmission unit of the nth stage of the gate drive units to the pull-up output end of the stage transmission unit of the nth-1 stage of the gate drive units.

[0012] Optionally, the repair circuit further comprises a third repair unit, the first repair unit comprises a first active switch, the second repair unit comprises a second active switch, and the third repair unit comprises a third active switch; the repair process further comprises: connecting the input end and the control end of the first active switch to the pull-down output end of the stage transmission unit of the gate drive unit of the n+1th stage; connecting the output end of the first active switch to the pull-down output end of the stage transmission unit of the gate drive unit of the n th stage; connecting the input end and the control end of the second active switch to the pull-up output end of the stage transmission unit of the gate drive unit of the n-1th stage; connecting the output end of the second active switch to the pull-up output end of the stage transmission unit of the gate drive unit of the n th stage; connecting the input end and the control end of the third active switch to the pull-up output end of the stage transmission unit of the gate drive unit of the n+1th stage; and connecting the output end of the third active switch to the pull-up output end of the stage transmission unit of the gate drive unit of the n th stage.

[0013] Optionally, the pull-up output end of the stage transmission unit of the gate drive unit of the n th stage is connected to the pull-up unit of the stage transmission unit of the gate drive unit of the n+k th stage through a pull-up wire, and the pull-down output end of the stage transmission unit of the gate drive unit of the n th stage is connected to the pull-down unit of the stage transmission unit of the gate drive unit of the n-k th stage; wherein the first cutting line is arranged on the side close to the gate drive unit of the pull-up wire, and the second cutting line is arranged on the side close to the gate drive unit of the pull-down wire; the repair process further comprises: cutting the pull-up wire connected to the pull-up output end of the stage transmission unit of the gate drive unit of the n th stage along the first cutting line, so as to disconnect the pull-up wire from the pull-up output end of the stage transmission unit of the gate drive unit of the n th stage; and cutting the pull-down wire connected to the pull-down output end of the stage transmission unit of the gate drive unit of the n th stage along the second cutting line, so as to disconnect the pull-down wire from the pull-down output end of the stage transmission unit of the gate drive unit of the n th stage.

[0014] The application further discloses a display device comprising the display panel driven by the gate drive circuit and a shell for accommodating the display panel.

[0015] The application sets a repair circuit in each gate drive unit, uses the repair circuit to repair the output of the stage transmission unit, so that in the case that the stage transmission unit of the current gate drive unit is damaged, the normal operation of the entire gate drive circuit can be realized by means of the pull-up signal or the pull-down signal output by the stage transmission unit in the adjacent gate drive unit, avoiding that the damage of the stage transmission unit of one gate drive unit leads to the failure of the row-by-row scanning of this gate drive circuit, and leads to the scrapping of the display panel. The application only needs to set corresponding first and second repair units in each gate drive unit, when the panel detects that the failure of the gate drive circuit is caused by the failure of the stage transmission unit, the first and second repair units are used to make the pull-up output end and the pull-down output end of the stage transmission unit of the failed gate drive unit connected to the adjacent gate drive unit, and the row-by-row scanning is completed by means of the stage transmission unit of the adjacent gate drive unit, which is relatively low in repair cost, and basically does not affect the display effect after repair. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and constitute a part of the specification, illustrate the embodiments of the application and together with the text of the specification serve to explain the principles of the application. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings. In the drawings:

[0017] Figure 1 is a schematic diagram of the gate drive circuit of the application;

[0018] Figure 2 is a schematic diagram of the gate drive unit of the application;

[0019] Figure 3 is an output waveform diagram of the pull-up signal, the pull-down signal and the first node of the application;

[0020] Figure 4 is a step diagram of the repair method of the gate drive circuit of the application;

[0021] Figure 5 is a repair diagram of the failure of the stage transmission unit of the nth gate drive unit of the application;

[0022] Figure 6 is a repair diagram of the failure of the stage transmission unit of the third gate drive unit of the application;

[0023] Figure 7 is a schematic diagram of the display device of the application.

[0024] Wherein, 100, gate drive circuit; 110, gate drive unit; 111, pull-up unit; 112, stage transmission unit; 113, pull-down unit; 114, output unit; 121, first repair unit; 122, second repair unit; 123, third repair unit; T1, first thin film transistor; T2, second thin film transistor; T3, third thin film transistor; T4, fourth thin film transistor; 130, pull-up wire; 131, pull-down wire; 132, first cutting line; 133, second cutting line; 200, display device; 210, display panel; 220, shell. DETAILED DESCRIPTION

[0025] It should be understood that the terms used herein, the specific structure and functional details disclosed, are only for the purpose of describing specific embodiments, and are representative, but the application can be embodied in many alternative forms, and should not be interpreted as being limited to the embodiments described herein.

[0026] In the description of the present application, the terms "first", "second" are only for the purpose of description, and should not be understood as indicating relative importance, or implying the number of indicated technical features. Therefore, unless otherwise specified, the features defined with "first", "second" can explicitly or implicitly include one or more of the features; "multiple" means two or more. In addition, the terms indicating the orientation or positional relationship such as "up", "down", "left", "right", "vertical", "horizontal", etc. are described based on the orientation or relative positional relationship shown in the drawings, and are only for the purpose of facilitating the simplified description of the present application, and should not be understood as indicating that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present application. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0027] The present application will be described in detail below with reference to the accompanying drawings and optional embodiments.

[0028] Figure 1 is a schematic diagram of the gate drive circuit 100 of the present application, see Figure 1As shown, the application discloses a gate drive circuit 100, which comprises a plurality of cascaded gate drive units 110 (G1-Gn) for sequentially turning on scan lines; each gate drive unit 110 comprises a pull-up unit 111, a stage transmission unit 112, a pull-down unit 113 and an output unit 114 (Gout1-Goutn), the pull-up unit 111 of the nth stage gate drive unit Gn is used for receiving a pull-up signal Cn-k output by the stage transmission unit 112 of the nth-k stage gate drive unit Gn-k; the pull-down unit 113 of the nth stage gate drive unit Gn is used for receiving a pull-down signal Rn+k output by the stage transmission unit 112 of the nth+k stage gate drive unit Gn+k; the pull-down output end of the stage transmission unit 112 of the nth stage gate drive unit Gn outputs a pull-down signal Rn to the pull-down unit 113 of the nth-k stage gate drive unit Gn-k, and the pull-up output end of the stage transmission unit 112 of the nth stage gate drive unit Gn outputs a pull-up signal Cn to the pull-up unit 111 of the nth+k stage gate drive unit Gn+k; the output unit 114 of the nth stage gate drive unit Gn outputs a scan signal to the nth scan line. Wherein the stage transmission unit of the nth stage gate drive unit outputs a pull-up signal Cn and a pull-down signal Rn.

[0029] Wherein the nth stage gate drive unit Gn further comprises a repair circuit, the repair circuit comprises a first repair unit 121 and a second repair unit 122, the first repair unit 121 is used for connecting the pull-down output end of the stage transmission unit 112 of the nth stage gate drive unit Gn and the pull-down output end of the stage transmission unit 112 of the nth+1 stage gate drive unit Gn+1 in a repair process; the second repair unit 122 is used for connecting the pull-up output end of the stage transmission unit 112 of the nth stage gate drive unit Gn and the pull-up output end of the stage transmission unit 112 of the nth+1 stage gate drive unit Gn+1 in a repair process; or connecting the pull-up output end of the stage transmission unit 112 of the nth stage gate drive unit Gn and the pull-up output end of the stage transmission unit 112 of the nth-1 stage gate drive unit Gn-1; wherein n, n-k, n+k, n+1 and n-1 are integers greater than 0.

[0030] The application sets the repairing circuit in each gate drive unit 110, uses the repairing circuit to repair the output of the stage transmission unit 112, so that in the case that the stage transmission unit 112 of the current gate drive unit 110 is damaged, the normal operation of the whole gate drive circuit 100 can be realized by means of the pull-up signal or the pull-down signal output by the stage transmission unit 112 in the adjacent gate drive unit 110, avoiding that the stage transmission unit 112 of one gate drive unit 110 is damaged, resulting in that the gate drive circuit 100 cannot realize line-by-line scanning, resulting in that the display panel is scrapped. The application only needs to set the corresponding first repairing unit 121 and the second repairing unit 122 in each gate drive unit 110, when the panel detects that the failure of the gate drive circuit 100 is caused by the failure of the stage transmission unit 112, the pull-up output end and the pull-down output end of the stage transmission unit of the failed gate drive unit 110 can be connected to the adjacent gate drive unit 110 by positioning the failed stage transmission unit 112 and using the first repairing unit 121 and the second repairing unit 122, so as to complete line-by-line scanning by means of the stage transmission unit 112 of the adjacent gate drive unit 110. Relatively speaking, the repair cost is low, and the display effect is basically not affected after repair.

[0031] It can be understood that the gate drive circuit 100 generally adopts a line-by-line scanning mode. When the current line is turned on, the gate drive unit 110 outputs a high-level signal to the corresponding scanning line through the output unit 114, so that the pixel thin film transistor on the current scanning line is in a conductive state and can charge the pixel, thereby realizing display. At this time, the current gate drive unit 110 is in a scanning state, and after the pixel on the current scanning line is charged, the current gate drive unit 110 is turned off and no longer outputs a high-level signal, so that the pixel thin film transistor on the current scanning line is cut off and no longer charges the pixel. After the current gate drive unit 110 is turned off, the next line gate drive unit 110 is turned on to charge the pixel corresponding to the next line scanning line, and line-by-line scanning is realized in turn. In a frame period, all pixels are charged from top to bottom. Of course, the line-by-line scanning mode is not limited to top-to-bottom, and both sides-to-middle or odd-numbered line and even-numbered line line-by-line scanning modes can be used, which are not limited herein.

[0032] Figure 2 is a schematic view of the gate drive unit 110 of the application, referring to Figure 2As shown, in the nth stage gate driving unit Gn, the pull-up unit 111 includes a first thin film transistor T1, the input terminal and the control terminal of the first thin film transistor T1 are connected to a pull-up signal, the pull-up signal can be the nth-k stage gate driving unit 110, and the output terminal of the first thin film transistor T1 is connected to a first node. Wherein, if n = 1 or 2, the input terminal and the control terminal of the first thin film transistor T1 can be connected to a frame start signal, and the first stage gate driving unit 110 and the second stage gate driving unit 110 are controlled by the frame start signal to start. The pull-down unit 113 can include a second thin film transistor T2 and a fourth thin film transistor T4, the input terminal of the second thin film transistor T2 and the input terminal of the fourth thin film transistor T4 are respectively connected to a gate-off voltage (VSS), the control terminals of the input terminals of the second thin film transistor T2 and the fourth thin film transistor T4 are respectively connected to a reset signal or a pull-down signal, the output terminal of the second thin film transistor T2 is connected to the first node, and the output terminal of the fourth thin film transistor T4 is connected to the output unit 114. The output unit 114 includes a third thin film transistor T3, and the control terminal of the third thin film transistor T3 is connected to the first node. Through the control of the reset signal and the pull-down signal, the output of the current gate driving unit 110 is turned off, so that the current row scanning line stops scanning. The stage transmission unit 112 converts the output of the output unit 114 into a pull-up signal and a pull-down signal respectively, and is used to control other gate driving units 110 to open and close through adjacent gate driving units 110, thereby forming a plurality of cascade arranged gate driving units 110.

[0033] Specifically, the stage transmission unit 112 is arranged in each gate driving unit 110, and the stage transmission unit 112 mainly transmits the pull-up signal or the pull-down signal to the corresponding gate driving unit 110. Taking the pull-up signal as an example, the main function of the pull-up signal is to output the pull-up signal to the gate driving unit 110 of the current row through the stage transmission unit 112 of the previous row or k rows in the on state, so that the voltage of the output unit 114 and the first node in the gate driving unit 110 respectively drops to the potential of the gate-off voltage, and the scanning line is no longer turned on.

[0034] Due to the cascade arrangement, the gate drive circuit 100 has a lower cost and a simpler circuit design, can be directly formed on the array substrate, thereby reducing the complexity of the driving chip of the display panel. Moreover, the use of the cascade function can reduce the number and length of the driving lines, reduce the complexity and power consumption of the circuit, and improve the driving efficiency and response speed. In addition, the cascade arrangement also greatly improves the overall performance of the display panel, which is helpful to realize a higher resolution and larger size display panel. However, if the cascade unit 112 of a certain stage cannot generate the pull-up signal or the pull-down signal, the corresponding gate drive unit 110 cannot be normally turned off or the corresponding gate drive unit 110 cannot be normally turned on, which is manifested as flickering or black lines of the row pixels, etc., resulting in a cascade failure. The present application can use the repair circuit to repair the failed cascade unit 112, so as to retransmit the pull-up signal and the pull-down signal, and realize the cascade of the circuit.

[0035] The gate drive circuit 100 of the present application can be directly formed on the array substrate, and the corresponding repair circuit is formed in each gate drive unit 110. The wire for transmitting the pull-up signal is defined as the pull-up wire 130, and the wire for transmitting the pull-down signal is defined as the pull-down wire 131, wherein the pull-up wire 130 is the wire between the pull-up output end of one gate drive unit 110 connected to the pull-up unit 111 of another gate drive unit 110, and the pull-down wire 131 is the wire between the pull-down output end of one gate drive unit 110 connected to the pull-down unit 113 of another gate drive unit 110.

[0036] For example, the pull-up output end of the cascade unit 112 of the nth stage gate drive unit Gn is connected to the pull-up unit 111 of the nth+k stage gate drive unit Gn+k through the pull-up wire 130, and the pull-down output end of the cascade unit 112 of the nth stage gate drive unit Gn is connected to the pull-down unit 113 of the nth-k stage gate drive unit Gn-k through the pull-down wire 131.

[0037] In an embodiment, in order to realize that when the cascade unit 112 of the nth stage gate drive unit Gn fails, the pull-up output end of the cascade unit 112 of the nth stage gate drive unit Gn is connected to the pull-up output end of the cascade unit 112 of the nth+1 stage gate drive unit Gn+1 in the repair process; at the same time, the pull-up output end of the cascade unit 112 of the nth stage gate drive unit Gn is connected to the pull-up output end of the cascade unit 112 of the nth-1 stage gate drive unit Gn-1. The present application also provides a third repair unit 123.

[0038] The repair circuit further comprises a third repair unit 123, the second repair unit 122 is configured to connect the pull-up output end of the stage transmission unit 112 of the nth-stage gate drive unit Gn and the pull-up output end of the stage transmission unit 112 of the (n-1)-th-stage gate drive unit Gn-1 in the repair process; the third repair unit 123 is configured to connect the pull-up output end of the stage transmission unit 112 of the nth-stage gate drive unit Gn and the pull-up output end of the stage transmission unit 112 of the (n+1)-th-stage gate drive unit Gn+1 in the repair process; wherein, when the stage transmission unit 112 of the nth-stage gate drive unit Gn fails, the second repair unit 122 and the third repair unit 123 work respectively, so that the pull-up output end of the (n-1)-th-stage gate drive unit Gn-1 and the pull-up output end of the (n+1)-th-stage gate drive unit Gn+1 are connected to the pull-up output end of the nth-stage gate drive unit Gn, and the pull-up unit 111 of the (n+k)-th-stage gate drive unit Gn+k is provided with a pull-up signal.

[0039] Since the pull-up signal output by the nth-stage gate drive unit Gn is provided to the pull-up unit 111 of the (n+k)-th-stage gate drive unit 110 and is used to charge the first node. When the pull-up signal output by the nth-stage gate drive unit Gn fails, whether the pull-up signal of the (n-1)-th-stage gate drive unit 110 or the pull-up signal of the (n+1)-th-stage gate drive unit 110 is used to the (n+k)-th-stage gate drive unit 110, due to the interval of about one row opening time in time, it will cause the first node to fail to reach the preset potential, therefore, through the second repair unit 122 and the third repair unit 123, the pull-up signal output by the nth-stage gate drive unit Gn is provided by the pull-down signal of the (n-1)-th-stage gate drive unit 110 and the pull-up signal of the (n+1)-th-stage gate drive unit 110.

[0040] The waveform diagram corresponding to the repair after the third repair unit 123 is used is shown in Figure 3 Figure 3 ​is an output waveform diagram of the pull-up signal, the pull-down signal and the first node of the application, taking the pull-up signal output fault of the nth gate drive unit Gn as an example, k = 4, the waveforms of the pull-up signals output by the nth-4 stage, the nth stage and the nth+4 stage of the stage transmission unit 112 respectively, and the potential change diagrams of the first nodes of the nth-4 stage, the nth stage and the nth+4 stage. As can be seen, when the pull-up wire 130 of the nth gate drive unit Gn fails to output, the pull-up wire 130 of the nth-1 gate drive unit 110 is simultaneously pre-charged for the first node of the nth+4 gate drive unit 110 when the first node is at a high level, and due to the effect of the third repair unit 123, the pull-up wire 130 of the nth+1 gate drive unit 110 is simultaneously pre-charged for the first node of the nth+4 gate drive unit 110 when the first node is at a high level. The pull-down unit 113 of the nth-4 gate drive unit 110 is controlled to lower the potential by the pull-down wire 131 of the nth+1 gate drive unit 110.

[0041] It can be understood that the application can also be repaired only by the second repair unit 122, and relatively speaking, the addition of the third repair unit 123 makes the waveform output by the gate drive unit 110 closer to the output waveform of the gate drive unit 110 before the fault.

[0042] Among them, the repair circuit can adopt the repair line mode to connect the adjacent stage transmission units 112. Specifically, the first repair unit 121 includes a first repair line; the second repair unit 122 includes a second repair line; and the third repair unit 123 includes a third repair line.

[0043] In this scheme, the first repair line can be directly arranged between the adjacent stage transmission units 112. Specifically, the second repair line and the third repair line are arranged on the adjacent two pull-up wires 130, and the first repair line is arranged on the adjacent two pull-down wires 131, and the first repair line, the second repair line and the third repair line are located in the same film layer, and the pull-up wire 130 and the pull-down wire 131 are located in the same film layer. In the case where repair is not required, the first repair line and the second repair line are in a suspended state. In the case where repair is required, the film layer where the first repair line is located and the film layer where the pull-up wire 130 is located are fused together by means of laser to realize the conduction of current. Specifically, the first repair line and the second repair line can be located in the second metal layer, and the pull-up wire 130 and the pull-down wire 131 can be located in the first metal layer.

[0044] In another embodiment, the first repair unit 121 comprises a first active switch; the second repair unit 122 comprises a second active switch, and the third repair unit 123 comprises a third active switch; after the repair process of the stage transmission unit 112 of the nth stage gate drive unit Gn, the input end and the control end of the first active switch are connected to the pull-down output end of the stage transmission unit 112 of the nth+1 stage gate drive unit Gn+1; the output end of the first active switch is connected to the pull-down output end of the stage transmission unit 112 of the nth stage gate drive unit Gn; the input end and the control end of the second active switch are connected to the pull-up output end of the stage transmission unit 112 of the nth-1 stage gate drive unit Gn-1; the output end of the second active switch is connected to the pull-up output end of the stage transmission unit 112 of the nth stage gate drive unit Gn; the input end and the control end of the third active switch are connected to the pull-up output end of the stage transmission unit 112 of the nth+1 stage gate drive unit Gn+1; and the output end of the third active switch is connected to the pull-up output end of the stage transmission unit 112 of the nth stage gate drive unit Gn.

[0045] In the present scheme, the active switch is used to replace the repair line in the previous embodiment. It is worth mentioning that the connection mode of the active switch is basically the same as that of the repair line, but since the active switch has a control end, the conduction and cut-off of the active switch can be controlled. In an embodiment, the control ends of the first active switch, the second active switch and the third active switch corresponding to the nth stage gate drive unit Gn are respectively connected to the adjacent pull-up wire 130 or pull-down wire 131, and the control end is not connected to the pull-up wire 130 or pull-down wire 131 of the current nth stage gate drive unit Gn.

[0046] In the present scheme, the active switch is used to replace the repair line in the previous embodiment. It is worth mentioning that the connection mode of the active switch is basically the same as that of the repair line, but since the active switch has a control end, the conduction and cut-off of the active switch can be controlled. In an embodiment, the control ends of the first active switch, the second active switch and the third active switch corresponding to the nth stage gate drive unit Gn are respectively connected to the adjacent pull-up wire 130 or pull-down wire 131, and the control end is not connected to the pull-up wire 130 or pull-down wire 131 of the current nth stage gate drive unit Gn.

[0047] The gate drive circuit 100 is arranged on the glass substrate, the first repair unit 121, the second repair unit 122 and the third repair unit 123 are arranged in the same film layer; the pull-up wire 130 and the pull-down wire 131 are arranged in the same film layer. For example, when the first repair unit 121, the second repair unit 122 and the third repair unit 123 are repair lines respectively, the pull-up wire 130 and the pull-down wire 131 can be arranged on the first metal layer, and the first repair unit 121, the second repair unit 122 and the third repair unit 123 are arranged on the second metal layer. When the first repair unit 121, the second repair unit 122 and the third repair unit 123 are active switches respectively, the pull-up wire 130 and the pull-down wire 131 can be arranged on the first metal layer, the source and drain of the active switch are arranged on the second metal layer respectively, and the control end of the active switch can be arranged on the third metal layer or the first metal layer. Among them, the first metal layer and the second metal layer are isolated by an insulating layer to prevent electrical transmission between them.

[0048] It can be understood that, whether using a repair line or an active switch, since the repair unit and the pull-up wire 130 and the pull-down wire 131 are located in different film layers, the repair unit and the pull-up wire 130 and the pull-down wire 131 need to overlap each other, and subsequent selective connection can be achieved through a repair process. Corresponding to the above-mentioned gate drive circuit 100, the application also discloses a repair method of the gate drive circuit 100, of which the first repair unit 121 and the second repair unit 122 are taken as examples.

[0049] Figure 4 is a schematic diagram of the steps of the repair method of the gate drive circuit 100 of the application, as shown in Figure 4 The application discloses a repair method of a gate drive circuit 100, which comprises the following steps:

[0050] The repair method comprises:

[0051] S10: When flickering occurs in the row pixels of the display panel, the number of stages of the gate drive units in the gate drive circuit is determined according to the number of pixel rows;

[0052] S20: When the nth-stage gate drive unit fails, a repair process is used to repair the nth-stage gate drive unit;

[0053] The repair process comprises:

[0054] S21: The first repair unit is used to connect the pull-down output end of the stage transmission unit of the nth-stage gate drive unit with the pull-down output end of the stage transmission unit of the nth+1-stage gate drive unit;

[0055] S22: connecting the pull-up output end of the stage transmission unit of the nth stage gate drive unit with the pull-up output end of the stage transmission unit of the n+1 stage gate drive unit; or connecting the pull-up output end of the stage transmission unit of the nth stage gate drive unit with the pull-up output end of the stage transmission unit of the n-1 stage gate drive unit.

[0056] Specifically, when the stage transmission unit 112 of a certain stage cannot output, the corresponding first repair unit 121 and second repair unit 122 are fused together by laser to realize current conduction between different metal layers, and the output of the stage transmission unit 112 of the current row is completed by using the adjacent pull-up signal or pull-down signal.

[0057] Further, based on the scheme of using three repair units, specifically, the repair circuit further includes a third repair unit 123, the first repair unit 121 includes a first active switch, the second repair unit 122 includes a second active switch, and the third repair unit 123 includes a third active switch.

[0058] The repair process further includes:

[0059] S21: connecting the input end and control end of the first active switch with the pull-down output end of the stage transmission unit of the n+1 stage gate drive unit; and connecting the output end of the first active switch with the pull-down output end of the stage transmission unit of the nth stage gate drive unit.

[0060] S22a: connecting the input end and control end of the second active switch with the pull-up output end of the stage transmission unit of the n-1 stage gate drive unit; and connecting the output end of the second active switch with the pull-up output end of the stage transmission unit of the nth stage gate drive unit.

[0061] S22b: connecting the input end and control end of the third active switch with the pull-up output end of the stage transmission unit of the n+1 stage gate drive unit; and connecting the output end of the third active switch with the pull-up output end of the stage transmission unit of the nth stage gate drive unit.

[0062] In this scheme, the pull-down signal of the n+1 stage gate drive unit 110 is mainly used to replace the pull-down signal of the nth stage gate drive unit Gn, and the pull-up signals of the n-1 stage and n+1 stage gate drive units 110 are used to replace the pull-up signal of the nth stage gate drive unit Gn, so that even in the case of failure of the stage transmission signal of the nth stage gate drive unit Gn, row-by-row scanning can be realized.

[0063] Figure 5 is a repair schematic diagram of the stage transmission unit 112 of the nth stage gate drive unit Gn of the present application, Figure 6This is a schematic diagram illustrating the repair of a fault in the stage transmission unit 112 of the third-stage gate drive unit 110 of this application. Figure 6 and Figure 5 The difference is that, since the pull-up and pull-down signals output by the cascade unit have the same waveform, they can be output to different positions using the same output terminal, requiring only one cut-off line.

[0064] See Figures 5-6 As shown, the pull-up trace 130 has a first cutting line 132 on the side near the gate driving unit 110, and the pull-down trace 131 has a second cutting line 133 on the side near the gate driving unit 110. When the cascading unit 112 of the nth-stage gate driving unit Gn fails, the first cutting line 132 and the second cutting line 133 at both ends of the cascading unit 112 of the nth-stage gate driving unit Gn are cut. After the repair process of the cascading unit 112 of the nth-stage gate driving unit Gn, the input terminal and control terminal of the first active switch are connected to the pull-down trace 131 of the cascading unit 112 of the (n+1)th-stage gate driving unit Gn+1. The output terminal of the first active switch is connected to the pull-down trace 131 of the cascade unit 112 of the nth-stage gate driving unit Gn; the input terminal and control terminal of the second active switch are connected to the pull-up trace 130 of the cascade unit 112 of the (n-1)th-stage gate driving unit Gn-1; the output terminal of the second active switch is connected to the pull-up trace 130 of the cascade unit 112 of the nth-stage gate driving unit Gn; the input terminal and control terminal of the third active switch are connected to the pull-up trace 130 of the cascade unit 112 of the (n+1)th-stage gate driving unit Gn+1; the output terminal of the third active switch is connected to the pull-up trace 130 of the cascade unit 112 of the nth-stage gate driving unit Gn.

[0065] To prevent signal interference, the first cut line 132 and the second cut line 133 are positioned closer to the cascade unit 112 relative to the connection point, which refers to the connection point between the first repair unit 121, the second repair unit 122, the third repair unit 123 and the pull-up line 130 and the pull-down line 131. This design prevents the cascade signal from the adjacent gate drive unit 110 from entering the damaged cascade unit 112 of the nth gate drive unit Gn, thus preventing signal interference.

[0066] Specifically, the repair process also includes:

[0067] S23a: Cut the pull-up trace connected to the pull-up output terminal of the stage transmission unit of the nth stage gate driving unit along the first cutting line, so that the pull-up trace is disconnected from the pull-up output terminal of the stage transmission unit of the nth stage gate driving unit.

[0068] S23b: cutting a pull-down wire connected to a pull-down output end of a stage transmission unit of the nth stage gate drive unit along the second cutting line, and disconnecting the pull-down wire from the pull-down output end of the stage transmission unit of the nth stage gate drive unit.

[0069] Figure 7 is a schematic diagram of a display device of the present application, as shown in Figure 7 The display device 200 comprises a display panel 210 and a housing 220, the display panel is driven by the gate drive circuit 100 of any one of the above-mentioned embodiments to display a picture, and the housing 220 is used to accommodate the display panel.

[0070] The present application sets a repair circuit in each gate drive unit 110, uses the repair circuit to repair the output of the stage transmission unit 112, so that in the case that the stage transmission unit 112 of the current gate drive unit 110 is damaged, the pull-up signal or the pull-down signal output by the stage transmission unit 112 in the adjacent gate drive unit 110 can be used to realize the normal operation of the entire gate drive circuit 100, avoid the damage of the stage transmission unit 112 of one gate drive unit 110, and avoid the failure of the gate drive circuit 100 to realize line-by-line scanning, and the display panel is scrapped. The present application only needs to set corresponding first repair unit 121 and second repair unit 122 in each gate drive unit 110, when the panel detects that the failure of the gate drive circuit 100 is caused by the failure of the stage transmission unit 112, the pull-up output end and the pull-down output end of the stage transmission unit of the failed gate drive unit 110 can be connected to the adjacent gate drive unit 110 by positioning the failed stage transmission unit 112 and using the first repair unit 121 and the second repair unit 122, and the line-by-line scanning is completed by the stage transmission unit 112 of the adjacent gate drive unit 110. Relatively speaking, the repair cost is low, and the display effect is basically not affected after repair.

[0071] It should be noted that the inventive concept of the present application can form a very large number of embodiments, but the length of the application file is limited and cannot be listed one by one, so that the above-described embodiments or technical features can be combined to form new embodiments without conflict. After each embodiment or technical feature combination, the original technical effect will be enhanced.

[0072] The above is a further detailed description of the present application in combination with specific optional embodiments, and the specific implementation of the present application cannot be limited to these descriptions. For ordinary skilled persons in the technical field to which the present application belongs, without departing from the concept of the present application, a number of simple deductions or substitutions can be made, which should be regarded as falling within the protection scope of the present application.

Claims

1. A gate drive circuit comprising a plurality of gate drive units cascaded for sequentially turning on scan lines, each of the gate drive units comprising a pull-up unit, a stage transmission unit, a pull-down unit and an output unit, the pull-up unit of an nth stage of the gate drive units being configured to receive a pull-up signal output by the stage transmission unit of an n-kth stage of the gate drive units, the pull-down unit of the nth stage of the gate drive units being configured to receive a pull-down signal output by the stage transmission unit of an n+kth stage of the gate drive units, the pull-down output terminal of the stage transmission unit of the nth stage of the gate drive units being configured to output the pull-down signal to the pull-down unit of the n-kth stage of the gate drive units, the pull-up output terminal of the stage transmission unit of the nth stage of the gate drive units being configured to output the pull-up signal to the pull-up unit of the n+kth stage of the gate drive units, the output unit of the nth stage of the gate drive units being configured to output a scan signal to an nth scan line, characterized in that, the nth stage of the gate drive units further comprises a repair circuit, the repair circuit comprising a first repair unit and a second repair unit, the first repair unit being configured to connect the pull-down output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-down output terminal of the stage transmission unit of an n+1th stage of the gate drive units in a repair process, the second repair unit being configured to connect the pull-up output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-up output terminal of the stage transmission unit of the n+1th stage of the gate drive units or the pull-up output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-up output terminal of the stage transmission unit of an n-1th stage of the gate drive units in the repair process, wherein n, n-k, n+k, n+1 and n-1 are integers greater than 0. wherein The repair circuit further comprises a third repair unit, the second repair unit being configured to connect the pull-up output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-up output terminal of the stage transmission unit of the n-1th stage of the gate drive units in the repair process, the third repair unit being configured to connect the pull-up output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-up output terminal of the stage transmission unit of the n+1th stage of the gate drive units in the repair process, wherein when the stage transmission unit of the nth stage of the gate drive units fails, the second repair unit and the third repair unit work respectively, so that the pull-up output terminal of the n-1th stage of the gate drive units and the pull-up output terminal of the n+1th stage of the gate drive units are connected to the pull-up output terminal of the nth stage of the gate drive units, and the pull-up signal is provided to the pull-up unit of the n+kth stage of the gate drive units. The first repair unit comprises a first repair line, the second repair unit comprises a second repair line, and the third repair unit comprises a third repair line, the first repair line being configured to connect the pull-down output terminal of the stage transmission unit of the nth stage of the gate drive units with the pull-down output terminal of the stage transmission unit of the n+1th stage of the gate drive units in the repair process. ​ ​ 2. The gate drive circuit according to claim 1, characterized by ​ ​ ​ ​ 3. The gate drive circuit according to claim 2, characterized by ​ ​ The second repair line is used for connecting the pull-up output end of the stage transmission unit of the n-th gate drive unit with the pull-up output end of the stage transmission unit of the n-1-th gate drive unit in the repair process; The third repair line is used for connecting the pull-up output end of the stage transmission unit of the n-th gate drive unit with the pull-up output end of the stage transmission unit of the n+1-th gate drive unit in the repair process.

4. The gate drive circuit according to claim 2, characterized by The first repair unit comprises a first active switch; the second repair unit comprises a second active switch; and the third repair unit comprises a third active switch; After the stage transmission unit of the n-th gate drive unit is repaired in the repair process, The input end and the control end of the first active switch are connected with the pull-down output end of the stage transmission unit of the n+1-th gate drive unit; and the output end of the first active switch is connected with the pull-down output end of the stage transmission unit of the n-th gate drive unit; The input end and the control end of the second active switch are connected with the pull-up output end of the stage transmission unit of the n-1-th gate drive unit; and the output end of the second active switch is connected with the pull-up output end of the stage transmission unit of the n-th gate drive unit; The input end and the control end of the third active switch are connected with the pull-up output end of the stage transmission unit of the n+1-th gate drive unit; The output end of the third active switch is connected with the pull-up output end of the stage transmission unit of the n-th gate drive unit.

5. The gate drive circuit according to claim 4, characterized in that The pull-up output end of the stage transmission unit of the n-th gate drive unit is connected with the pull-up unit of the stage transmission unit of the n+k-th gate drive unit through a pull-up wire; and the pull-down output end of the stage transmission unit of the n-th gate drive unit is connected with the pull-down unit of the stage transmission unit of the n-k-th gate drive unit through a pull-down wire; The first cutting line is arranged on the side of the pull-up wire close to the gate drive unit; and the second cutting line is arranged on the side of the pull-down wire close to the gate drive unit; When the stage transmission unit of the n-th gate drive unit is faulty, the first cutting line and the second cutting line at both ends of the stage transmission unit of the n-th gate drive unit are cut; and after the stage transmission unit of the n-th gate drive unit is repaired in the repair process, The input end and the control end of the first active switch are connected with the pull-down wire of the stage transmission unit of the n+1-th gate drive unit; and the output end of the first active switch is connected with the pull-down wire of the stage transmission unit of the n-th gate drive unit; The input end and the control end of the second active switch are connected with the pull-up wire of the stage transmission unit of the n-1-th gate drive unit; and the output end of the second active switch is connected with the pull-up wire of the stage transmission unit of the n-th gate drive unit; The input end and the control end of the third active switch are connected with the pull-up wire of the stage transmission unit of the n+1-th gate drive unit; and the output end of the third active switch is connected with the pull-up wire of the stage transmission unit of the n-th gate drive unit.

6. The gate drive circuit according to claim 5, characterized by The gate drive circuit is arranged on a glass substrate, The first repair unit, the second repair unit and the third repair unit are arranged on the same film layer; the pull-up wire and the pull-down wire are arranged on the same film layer.

7. A repair method of a gate drive circuit, characterized by, The gate drive circuit is the gate drive circuit according to any one of claims 1-6, and the repair method comprises: When flickering occurs in the row pixels of the display panel, the number of pixel rows is used to determine the number of stages of the gate drive units in the gate drive circuit; When the nth-stage gate drive unit fails, the repair process is used to repair the nth-stage gate drive unit; The repair process comprises: The first repair unit is used to connect the pull-down output end of the stage transmission unit of the nth-stage gate drive unit to the pull-down output end of the stage transmission unit of the (n+1)th-stage gate drive unit; The second repair unit is used to connect the pull-up output end of the stage transmission unit of the nth-stage gate drive unit to the pull-up output end of the stage transmission unit of the (n+1)th-stage gate drive unit, or to connect the pull-up output end of the stage transmission unit of the nth-stage gate drive unit to the pull-up output end of the stage transmission unit of the (n-1)th-stage gate drive unit.

8. The repair method of the gate drive circuit according to claim 7, wherein The repair circuit further comprises a third repair unit, the first repair unit comprises a first active switch, the second repair unit comprises a second active switch, and the third repair unit comprises a third active switch; The repair process further comprises: The input end and the control end of the first active switch are connected to the pull-down output end of the stage transmission unit of the (n+1)th-stage gate drive unit, and the output end of the first active switch is connected to the pull-down output end of the stage transmission unit of the nth-stage gate drive unit; The input end and the control end of the second active switch are connected to the pull-up output end of the stage transmission unit of the (n-1)th-stage gate drive unit, and the output end of the second active switch is connected to the pull-up output end of the stage transmission unit of the nth-stage gate drive unit; The input end and the control end of the third active switch are connected to the pull-up output end of the stage transmission unit of the (n+1)th-stage gate drive unit, and the output end of the third active switch is connected to the pull-up output end of the stage transmission unit of the nth-stage gate drive unit.

9. The repair method of a gate driving circuit according to claim 7, wherein The pull-up output end of the stage transmission unit of the nth-stage gate drive unit is connected to the pull-up unit of the stage transmission unit of the (n+k)th-stage gate drive unit through a pull-up wire, and the pull-down output end of the stage transmission unit of the nth-stage gate drive unit is connected to the pull-down unit of the stage transmission unit of the (n-k)th-stage gate drive unit through a pull-down wire; The pull-up wire is provided with a first cutting line on the side close to the gate drive unit, and the pull-down wire is provided with a second cutting line on the side close to the gate drive unit; The repair process further comprises: The pull-up wire connected to the pull-up output end of the stage transmission unit of the nth-stage gate drive unit is cut along the first cutting line, so that the pull-up wire is disconnected from the pull-up output end of the stage transmission unit of the nth-stage gate drive unit; The pull-down wire connected to the pull-down output end of the stage transmission unit of the nth-stage gate drive unit is cut along the second cutting line, so that the pull-down wire is disconnected from the pull-down output end of the stage transmission unit of the nth-stage gate drive unit. The pull-down wire connected with the pull-down output end of the stage transmission unit of the nth stage gate drive unit is cut along the second cutting line, so that the pull-down wire is disconnected with the pull-down output end of the stage transmission unit of the nth stage gate drive unit.

10. A display device, characterized by comprising: The display panel driven by the gate drive circuit according to any one of claims 1-6, and a housing for accommodating the display panel.

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