CN100371778C - Display device - Google Patents

Abstract

A display device comprises a display panel, a driving circuit and a repair line. The display panel is provided with a display area and a peripheral circuit area positioned at the periphery of the display area, wherein the peripheral circuit area is provided with a driving circuit joint area and a plurality of leads extending from the display area to the driving circuit joint area. The driving circuit is electrically connected with the display area through the driving circuit bonding area and the conducting wires. The repair line is distributed in the peripheral circuit area and the drive circuit, wherein the repair line is provided with a repair structure, and the repair structure is positioned between the drive circuit joint area and the display area. The repair process of the display device provided by the invention is simpler, so that the cost and time of the back-end process can be reduced.

Description

display device

technical field

The invention relates to a display device, in particular to a display device with repair lines.

Background technique

Early display devices made of cathode ray tubes (cathode ray tube, CRT) had disadvantages such as large volume, heavy weight, high radiation, and poor image quality. Therefore, new flat-panel display technologies have been continuously developed. These newly developed flat-panel display devices have the advantages of thinness, power saving, low radiation, full color, etc., and they include liquid crystal display (liquid crystal display, LCD) devices, plasma display panel (PDP) devices, organic electro- Luminescent display (organic electroluminescent display, OELD) device, etc. Among these newly developed flat-panel display devices, liquid crystal display equipment is the most common and the technology is the most mature. Mobile phones, digital cameras, digital video cameras, personal digital assistants (personal digital assistant, PDA), notebook computers, LCD TVs, etc Each has its scope of application.

Although the technology of liquid crystal display devices has matured, some defects will inevitably occur in the manufacturing process of liquid crystal display panels, and these defects will cause sensory discomfort when displaying images on the liquid crystal display. If these defects are discarded directly The liquid crystal display panel will greatly increase the manufacturing cost. Generally speaking, it is very difficult to achieve zero defect rate only by improving the process technology, so the defect repair technology of the liquid crystal display panel becomes quite important. In the prior art, the disconnection repair of the liquid crystal display panel includes methods such as laser welding and laser cutting. However, due to the wiring design of the LCD panel, not every broken line can be quickly repaired, and even some broken lines cannot be repaired.

FIG. 1 shows a schematic structural diagram of a known liquid crystal display device. Referring to FIG. 1 , the liquid crystal display device 100 mainly includes a liquid crystal display panel 110 , a data control circuit board 120 , a scan control circuit board 130 , a plurality of data drivers 140 and a plurality of scan drivers 150 . Wherein, the liquid crystal display panel 110 has a plurality of data wiring lines 112 , a plurality of scanning wiring lines 114 and a repairing line 116 . A plurality of data drivers 140 are disposed between the data control circuit board 120 and the liquid crystal display panel 110, and are connected to the data control circuit board 120 and the liquid crystal display panel 110 by a tape automation bounding package. A plurality of data wires 112 are electrically connected. A plurality of scan drivers 150 are disposed between the scan control circuit board 130 and the liquid crystal display panel 110 , and are connected to the plurality of scan control circuit boards 130 and the liquid crystal display panel 110 through a tape-winding automatic bonding type package. The strip scan wires 114 are electrically connected. As can be seen from FIG. 1 , the data driver 140 and the scan driver 150 belong to a tape-and-reel automatic bonding package.

The data signal displayed on the screen is first transmitted to the data driver 140 through the data control circuit board 120 , and then transmitted to the data wiring 112 . The scanning signal displayed on the screen is first transmitted to the scanning driver 150 through the scanning control circuit board 130 , and then transmitted to the scanning wiring 114 . The scanning signal about the screen display is transmitted to the active components (not shown) on the liquid crystal display panel 110 through the scanning wiring 114, and the data signal about the screen display is written in corresponding to this through the data wiring 112. The pixel electrodes (not shown) of the active component enable the liquid crystal display panel 110 to achieve display effect.

Generally speaking, after the manufacture of the liquid crystal display panel 110 is completed, a liquid crystal cell test (cell test) process is performed first to check whether the liquid crystal display panel 110 is flawed. When it is found that the liquid crystal display panel 110 has a defect of disconnection, it must be repaired by the repair line 116 of the liquid crystal display panel 110 . For example, when a damaged data wiring 112 is detected on the liquid crystal display panel 110, laser welding can be performed at the welding points 116a and 116b to electrically connect the repair line 116 to the damaged data wiring 112, Most of the functions of the damaged data wires 112 can be recovered through the repair wires 116 . The liquid crystal display panel 110 that has been repaired needs to undergo a liquid crystal unit test again to ensure that the disconnection defect has been truly repaired. However, since the size of the panel is getting larger and the resolution is getting higher and higher, the repairing line 116 must cross more and more data wiring lines 112 and the length of the repairing line 116 is too long, resulting in the loss of the repairing line 116. If the parasitic capacitance and resistance are too large, the signal will be attenuated after the signal is transmitted over a long distance, resulting in poor display images of the liquid crystal display panel 110 .

FIG. 2A shows a schematic structural diagram of another known liquid crystal display device, which can improve the signal attenuation of the liquid crystal display device 100 in FIG. 1 . Please refer to FIG. 2A, the liquid crystal display device 200 is an embodiment disclosed in patent US6525705B1, which includes a liquid crystal display panel 210, a data control circuit board 220, a scan control circuit board 230, multiple data drivers 240 and multiple Scan driver 250 . Wherein, the liquid crystal display panel 210 has a plurality of data wiring lines 212 , a plurality of scanning wiring lines 214 , a first repair line 216 and a second repair line 218 . The data control circuit board 220 , the data driver 240 and the scan driver 250 are the same as the data control circuit board 120 , the data driver 140 and the scan driver 150 of the liquid crystal display device 100 . The scan control circuit board 230 has a third repair line 232 and an amplification circuit 234 . The amplifying circuit 234 is electrically connected to the third repairing line 232 and arranged in a path of the third repairing line 232 . In addition, the third repairing line 232 is electrically connected to the first repairing line 216 and the second repairing line 218 via a tape-and-roll automatic bonding package.

When a damaged data line 212 is detected on the liquid crystal display panel 210, laser welding can be performed at the welding points 216a and 218a respectively to connect the first repair line 216, the second repair line 218 and the damaged data line. The wires 212 are electrically connected. When the liquid crystal display panel 210 is bonded with the data control circuit board 220 and the scan control circuit board 230, that is, after the bounding process is completed, the damaged data wiring 212 can pass through the first repair line 216, the third Repair line 232 and second repair line 218 restore most of the functions. Since there is an amplifier circuit 234 on the path of the third repair line 232, the signal transmitted through the third repair line 232 can be amplified by the amplifier circuit 234, so it can solve the problem of signal attenuation due to long-distance transmission after the signal passes through the repair line 218 The problem. However, as the size of the panel becomes larger and the resolution becomes higher, the parasitic capacitance of the repair lines 216 and 218 will become larger and larger, and under the limited driving capability of the data driver 240 and the scan driver 250, the Signals transmitted by lines 216 and 232 will also experience signal attenuation.

In addition to the above-mentioned liquid crystal display devices 100 and 200 , there are other known liquid crystal display panels with a repair line design. 2B and 2C are schematic structural diagrams of another liquid crystal display device, both of which can improve the signal attenuation problem mentioned above. Please refer to FIG. 2B and 2C. The liquid crystal display devices 200' and 200" shown in FIG. 2B and FIG. The design of the lines 222', 222" can reduce the parasitic capacitance of the repair lines 222', 222", so that the disconnection defects of the liquid crystal display panels 210', 210" of the liquid crystal display devices 200', 200" can be repaired, but these two The liquid crystal display panels 210', 210" of the liquid crystal display devices 200', 200" cannot detect the repaired situation in the liquid crystal unit test stage after repairing, and because of such a segmented design, an additional post-stage process must be added to The connection of repair lines is made on the data control circuit boards 220 ′, 220 ″, which will increase the cost and time of the subsequent process.

Contents of the invention

In view of the above reasons, the object of the present invention is to provide a display device that can reduce the cost and time of the back-end process.

Based on the above objective or other objectives, the present invention provides a display device including a display panel, a driving circuit and a repair line. The display panel has a display area and a peripheral circuit area located on the periphery of the display area, wherein the peripheral circuit area has a driving circuit bonding area and a plurality of wires extending from the display area to the driving circuit bonding area. The driving circuit is electrically connected to the display area through the driving circuit bonding area and these wires. The repairing line is distributed in the peripheral circuit area and the driving circuit, wherein the repairing line has a repairing structure, and the repairing structure is located between the driving circuit bonding area and the display area.

In the display device according to the preferred embodiment of the present invention, the repair structure is, for example, a disconnection point or a switch.

According to the display device described in the preferred embodiment of the present invention, the display panel includes, for example, a liquid crystal display panel, a plasma display panel, an organic electroluminescence display panel, an inorganic electroluminescent display panel, a vacuum fluorescent display panel, a field emission display panel, etc. panel or electrochromic display panel.

In the display device according to a preferred embodiment of the present invention, the wires include data wires or scan wires, for example.

In the display device according to the preferred embodiment of the present invention, the driving circuit includes, for example, a driver and a control circuit board. The control circuit board drives the display panel through the driver.

In the display device according to the preferred embodiment of the present invention, the driver is, for example, a flip-chip chip, and the flip-chip chip is directly electrically connected to the bonding area of the driving circuit.

According to the display device described in the preferred embodiment of the present invention, the driver is, for example, a tape-and-roll package, and the tape-and-roll package is electrically connected to the control circuit board and the drive circuit bonding area.

In the display device according to the preferred embodiment of the present invention, the driver is configured on the control circuit board to be electrically connected to the bonding area of the driving circuit, for example.

According to an embodiment of the present invention, the display device may further include, for example, a first amplifier configured in the driver, wherein the first amplifier is electrically connected to the repair line, and the first amplifier is adapted to amplify a signal transmitted by the repair line. In addition to the first amplifier, for example, the display device may further include a second amplifier disposed on the control circuit board, wherein the second amplifier is electrically connected to the repair line, and the second amplifier is suitable for amplifying the signal transmitted by the repair line.

According to an embodiment of the present invention, the display device may further include, for example, a first switch disposed on the control circuit board, wherein the first switch is connected between the first amplifier and the repair line to determine whether to pass through the first The signal amplified by the amplifier is output to the repair line. In addition to a switcher, for example, the display device may further include a second switcher disposed on the control circuit board, wherein the second switcher is connected between the second amplifier and the repair line to determine whether to pass through the second The signal amplified by the amplifier is output to the repair line.

According to an embodiment of the present invention, the display device may further include, for example, a second amplifier disposed on the control circuit board without matching the first amplifier, wherein the second amplifier is electrically connected to the repair line, and the second amplifier is suitable for amplifying and repairing signal transmitted by the line. In addition, the display device may further include, for example, a second switcher disposed on the control circuit board, wherein the second switcher is connected between the second amplifier and the repair line to determine whether the signal amplified by the second amplifier Output to patch lines.

The repair line of the display device of the present invention has a repair structure, because the repair structure is located between the driving circuit junction area and the display area, so that the repaired display panel can confirm whether the defect is indeed repaired during the test of the liquid crystal unit, so it can reduce the cost. process time and cost.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 shows a schematic structural diagram of a liquid crystal display device.

FIG. 2A shows a schematic structural diagram of another liquid crystal display device.

FIG. 2B shows a schematic structural diagram of another liquid crystal display device.

FIG. 2C shows a schematic structural diagram of another liquid crystal display device.

FIG. 3 shows a schematic structural diagram of a display device according to a first embodiment of the present invention.

FIG. 4 shows a schematic structural diagram of a display device according to a second embodiment of the present invention.

FIG. 5 shows a schematic structural diagram of a display device according to a third embodiment of the present invention.

FIG. 6 shows a schematic structural diagram of a display device according to a fourth embodiment of the present invention.

Description of reference symbols

100, 200, 200’, 200”: liquid crystal display device

110, 210, 210’, 210”: LCD panel

112, 212, 212’, 212”, D: data wiring

114, 214, 214’, 214”, S: scan wiring

116, 216, 216’, 216”, 218, 222’, 222”, 232, 232’, 232”, 330, 430, 530, 630: repair line

116a, 116b, 216a, 216a', 216a", 218a, 222a', 222a", 334a, 334b, 434a, 434b, 534a, 534b, 634a, 634b: welding points

120, 220, 220’, 220”: data control circuit board

130, 230, 230’, 230”: scan control circuit board

234, 234’, 234”: amplifier circuit

140, 240, 240’, 240”: data drive

150, 250, 250’, 250”: scan drive

300, 400, 500, 600: display device

310: display panel

312: display area

314: Peripheral circuit area

314a: Drive circuit bonding area

316: wire

320: drive circuit

322: drive

324a, 324b: control circuit board

332, 432, 532, 632: Repairing structures

340, 360: Amplifier

350, 370: switcher

Detailed ways

first embodiment

FIG. 3 shows a schematic structural diagram of a display device according to a first embodiment of the present invention. Please refer to FIG. 3 , the display device 300 of the present invention mainly includes a display panel 310 , a driving circuit 320 , and a repair line 330 . In addition, in addition to the above-mentioned necessary components, the display device 300 of the present invention may also include at least a first amplifier 340, a first switcher 350, a second amplifier 360, a second switcher 370 and combinations thereof as appropriate. one of them.

The display panel 310 is, for example, a liquid crystal display panel, a plasma display panel, an organic electroluminescent display panel, an inorganic electroluminescent display panel, a vacuum fluorescent display panel, a field emission display panel, or an electrochromic display panel, etc., which has a display area 312 and a peripheral circuit area 314 . Wherein, the peripheral circuit area 314 is located at the periphery of the display area 312 and has a driving circuit bonding area 314 a and a plurality of wires 316 . These multiple wires 316 extend from the display area 312 to the driving circuit bonding area 314a, and the wires 316 can be divided into data wires D and scan wires S according to their configured positions and functions.

The driving circuit 320 is electrically connected to the display area 312 through a plurality of wires 316 at the driving circuit bonding area 314a, and includes at least one driver 322 and control circuit boards 324a, 324b. The control circuit boards 324a and 324b drive the display panel 310 through the driver 322, the control circuit board 324a controls the signal input of the data wiring D, and the control circuit board 324b controls the signal input of the scanning wiring S. In addition, each driver 322 is configured with a first amplifier 340 . In this embodiment, the driver 322 is an automatic tape-and-reel package, and the automatic tape-and-reel package is electrically connected between the control circuit board 324a and the driving circuit bonding area 314a, or is electrically connected to the control circuit board 324b. Between the bonding area 314a and the driving circuit. In another embodiment, the driver 322 can be a flip-chip chip, and the flip-chip chip is directly electrically connected to the driving circuit bonding region 314a, which is the so-called chip-panel bonding technology (chip onglass, COG). In yet another embodiment, the driver 322 is disposed on the control circuit boards 324a, 324b to be electrically connected to the driving circuit bonding area 314a, which is a so-called chip on board (COB) technology. In yet another embodiment, the driver 322 can be a flip-chip chip, and the flip-chip chip is connected to a flexible board, and the flexible board is electrically connected between the control circuit board 324a and the driving circuit bonding area 314a, or is electrically connected to Between the control circuit board 324b and the driving circuit bonding area 314a is the so-called chip-on-film (COF) bonding technology.

The repair line 330 is distributed in the peripheral circuit area 314 and the driving circuit 320 , and the repair line 330 has a repair structure 332 . The repair structure 332 is located between the driving circuit bonding area 314 a and the display area 312 . In this embodiment, the repair structure 332 is a discontinuous point. In another embodiment, the repair structure 332 can be a toggle switch.

The first amplifier 340 is configured in one or more of the drivers 322, and at least one of the first amplifiers 340 is electrically connected to the repair line 330. These first amplifiers 340 electrically connected to the repair line 330 can be used to amplify the signal transmitted by the repair line 330 signal. The first switcher 350 is disposed on the control circuit board 324 a and connected between the first amplifier 340 and the repair line 330 to determine whether to output the signal amplified by the first amplifier 340 to the repair line 330 .

The second amplifier 360 is disposed on the control circuit board 324 a and electrically connected to the repair line 330 , and can be used to amplify the signal transmitted by the repair line 330 . The second switcher 370 is disposed on the control circuit board 324 a and is connected between the second amplifier 360 and the repair line 330 to determine whether to output the signal amplified by the second amplifier 360 to the repair line 330 .

When a damaged data wiring D is detected on the display panel 310, laser welding is first performed at the welding points 334a and 334b to electrically connect the repair line 330 to the damaged data wiring D, and then repair The two ends of the repaired structure 332 of the line 330 are burnt with a laser to burn the protective layer on the repaired line 330, and then a thin metal layer is formed to connect the two ends of the repaired structure 332 by laser chemical vapor deposition (laser chemical vapor deposition, laser CVD) method . In addition, laser welding technology can also be used to weld the repair lines 330 at both ends of the repair structure 332 together, so as to save the time of the repair process. After the display panel 310 completes the module process, most of the functions of the damaged circuit can be recovered by repairing the line 330 . Since there are the first amplifier 340 and the second amplifier 360 on the path of the repair line 330, the signal transmitted through the repair line 330 can be amplified by the first amplifier 340 and/or the second amplifier 360, so the signal will not be damaged after long-distance transmission. There will be a problem of signal attenuation. After the liquid crystal display panel 310 is repaired, a second liquid crystal unit test can be performed to confirm whether the welding points 334 a and 334 b are welded and whether the two ends of the repaired structure 332 are connected properly. In other words, before the display device 300 is completed, the repair status of the display panel 310 can be known through the liquid crystal unit test, thus reducing the loss of time and cost of the subsequent process.

In addition, since both the first amplifier 340 and the second amplifier 360 can independently amplify the signal transmitted by the repair line 330, after the display panel 310 is repaired, the first switcher 350 and the second switcher 370 can be adjusted according to requirements to selectively repair The signal transmitted by the line 330 is amplified by the first amplifier 340 and/or the second amplifier 360 . In more detail, if the power of the first amplifier 340 or the second amplifier 360 to amplify the signal alone is insufficient, after the display panel 310 is repaired, the first switch 350 and the second switch 370 can be adjusted to make the repair line 330 The transmitted signal is jointly amplified by the first amplifier 340 and the second amplifier 360 .

It is worth noting that although this embodiment is described with the example in which the repair line 330, the first switch 350, the second amplifier 360 and the second switch 370 are located on the control circuit board 324a, the above-mentioned repair on the control circuit board 324a The structure of the line 330 and the design of the amplifier circuit can all be applied to the control circuit board 324b. In addition, the display device 300 of this embodiment may not include the first switcher 350 and the second switcher 370, so that after the display panel 310 is repaired, the signal transmitted by the repair line 330 is directly passed through the first amplifier 340 and the second amplifier 340. Amplifier 360 zooms in.

second embodiment

FIG. 4 shows a schematic structural diagram of a display device according to a second embodiment of the present invention. Referring to FIG. 4 , the display device 400 of the present invention is similar to the display device 300 of the first embodiment, except that the display device 400 has a plurality of first amplifiers 340 and a plurality of first switches 350 . Each amplifier 340 is electrically connected to the repair line 430 and configured in the corresponding driver 322 . Each first switcher 350 is configured on the control circuit board 324 a and connected between the corresponding first amplifier 340 and the repairing line 430 .

Similar to the first embodiment, after the display panel 310 is repaired, the first switcher 350 and the second switcher 370 can be adjusted according to the requirement, so as to select that the signal transmitted by the repair line 430 is jointly amplified by several first amplifiers 340, Or only amplified by the second amplifier 360 . In more detail, when the power of the signal amplified jointly by several first amplifiers 340 or independently amplified by the second amplifier 360 is insufficient, the manufacturer can also adjust the first switcher 350 and the second switcher 370 to The signal transmitted by the repair line 430 is jointly amplified by several first amplifiers 340 and one second amplifier 360 .

In addition, the repairing method for disconnection defects and the advantages of the repairing line 430 are the same as those described in the first embodiment, and the structure of the repairing line 430 on the control circuit board 324a, the design of the amplifier circuit, etc. Both can be applied to the control circuit board 324b.

third embodiment

FIG. 5 shows a schematic structural diagram of a display device according to a third embodiment of the present invention. Please refer to FIG. 5, the display device 500 of the present invention is similar to the display device 300 of the first embodiment, the difference is that: the display device 500 does not have components similar to the first amplifier 340 and the first switcher 350 of the display device 300, And there is only a second amplifier 360 and a second switch 370 . After the display panel 310 is repaired, the second switch 370 can be adjusted according to requirements, so that the signal transmitted by the repair line 530 can be amplified by the second amplifier 360 .

In addition, the repairing method of the broken line defect and the advantages of the repairing line 530 are the same as those described in the first embodiment, and the structure of the repairing line 530 and the design of the amplifier circuit of the control circuit board 324a in this embodiment are all the same. Applicable to the control circuit board 324b.

It should be noted that the display device 500 of this embodiment may not have the second switcher 370 . After the display panel 310 is repaired, the signal transmitted by the repair line 530 is directly amplified by the second amplifier 360 .

Fourth embodiment

FIG. 6 shows a schematic structural diagram of a display device according to a fourth embodiment of the present invention. Please refer to FIG. 6, the display device 600 of the present invention is similar to the display device 300 of the first embodiment, the difference is that: the display device 600 does not have components similar to the second amplifier 360 and the second switcher 370 of the display device 300, And there is at least a first amplifier 340 and a first switch 350 . The manufacturer can adjust the first switch 350 according to requirements, so that the signal transmitted by the repair line 630 can be amplified by one or several first amplifiers 340 .

In addition, the repairing method of the broken line defect and the advantages of the repairing line 630 are the same as those described in the first embodiment, and the structure of the repairing line 630 of the control circuit board 324a and the design of the amplifier circuit in this embodiment are all the same. Applicable to the control circuit board 324b.

It should be noted that the display device 600 of this embodiment may not have the first switcher 350 . When repairing the display panel 310 , the repairing wire 630 at both ends of the repairing structure 632 can be connected, so that the signal transmitted by the repairing wire 630 is directly amplified by the first amplifier 340 .

In summary, the display device of the present invention has at least the following advantages:

1. In the display panel of the display device proposed by the present invention, at least one amplifier is electrically connected to the repair line, which can solve the problem of signal attenuation after being transmitted through the repair line, thus improving the display image.

2. The repair line of the display device proposed by the present invention has a repair structure, which is located between the drive circuit junction area and the display area, so that the display panel can confirm whether the defect is indeed repaired during the test of the liquid crystal unit, without additional It can be confirmed by the back-end process, so the time and cost of the back-end process can be reduced.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection is based on the claims of the present invention.

Claims (10)

1. A display device, comprising: A display panel with a display area and a peripheral circuit area located on the periphery of the display area, wherein the peripheral circuit area has a driving circuit bonding area and a plurality of wires extending from the display area to the driving circuit bonding area; a driving circuit electrically connected to the display area through the driving circuit bonding area and the wires; and A repairing line is distributed in the peripheral circuit area and the driving circuit, wherein the repairing line has a repairing structure, and the repairing structure is located between the driving circuit bonding area and the display area. 2. The display device as claimed in claim 1, wherein the repair structure is a disconnection point or a switch. 3. The display device according to claim 1, wherein the driving circuit comprises: at least one driver; and A control circuit board, wherein the control circuit board drives the display panel through the driver. 4. The display device as claimed in claim 3, wherein the driver is a flip chip, and the flip chip is directly electrically connected to the driving circuit bonding area. 5. The display device as claimed in claim 3, further comprising a first amplifier disposed in the driver, wherein the first amplifier is electrically connected to the repair line, and the first amplifier is adapted to amplify the signal transmitted by the repair line signal. 6. The display device as claimed in claim 5, further comprising a first switch configured on the control circuit board, wherein the first switch is connected between the first amplifier and the repair line to determine whether Output the signal amplified by the first amplifier to the repair line. 7. The display device according to claim 5, further comprising a second amplifier disposed on the control circuit board, wherein the second amplifier is electrically connected to the repair line, and the second amplifier is adapted to amplify the repair line the signal transmitted. 8. The display device according to claim 7, further comprising a second switcher disposed on the control circuit board, wherein the second switcher is connected between the second amplifier and the repair line to determine whether Output the signal amplified by the second amplifier to the repair line. 9. The display device according to claim 3, further comprising a second amplifier disposed on the control circuit board, wherein the second amplifier is electrically connected to the repair line, and the second amplifier is adapted to amplify the repair line the signal transmitted. 10. The display device according to claim 9, further comprising a second switcher disposed on the control circuit board, wherein the second switcher is connected between the second amplifier and the repair line to determine whether Output the signal amplified by the second amplifier to the repair line.

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