Circuit board assembly and liquid crystal display module

Abstract

The utility model discloses a circuit board assembly, comprising a screen circuit board which is used for being electrically connected with a liquid crystal screen and is provided with a first bonding pad; and the backlight circuit board is used for being electrically connected with a backlight assembly, is provided with a second bonding pad and a solid conductive adhesive tape, is used for being electrically connected with the screen circuit board and the backlight circuit board, and is bonded between the first bonding pad and the second bonding pad. The circuit board assembly is convenient for height management and control, and avoids interference on a casing of the display terminal. The utility model further discloses a liquid crystal display module which comprises the circuit board assembly.

Description

Technical Field

[0001] The utility model relates to display technology, in particular to a circuit board component and a liquid crystal display module. Background Art

[0002] The liquid crystal display module includes a liquid crystal screen and a backlight assembly. The circuit board of the backlight assembly is generally welded on the circuit board of the liquid crystal screen to be electrically connected to the main control board of the display terminal through the circuit board of the liquid crystal screen.

[0003] At present, the circuit board of the backlight assembly and the circuit board of the LCD screen are welded by tin wire. After welding, there will be solder between the two layers of circuit boards. The solder will have a certain height. Therefore, terminal manufacturers need to reserve a certain avoidance space at the position corresponding to the solder when designing the display terminal housing. However, the solder will have a certain fluidity during welding, and its height after solidification is not easy to control. There is a risk of exceeding the height standard. The solder with an excessive height will interfere with the display terminal housing and affect the terminal assembly. Utility Model Content

[0004] In order to solve the above-mentioned deficiencies of the prior art, the utility model provides a circuit board assembly, which is convenient for height control and avoids interference with the casing of the display terminal.

[0005] The utility model also provides a liquid crystal display module, comprising the above-mentioned circuit board assembly.

[0006] The technical problem to be solved by the utility model is achieved through the following technical solutions:

[0007] A circuit board assembly is used for a liquid crystal display module, wherein the liquid crystal display module comprises a liquid crystal screen and a backlight assembly; the circuit board assembly comprises:

[0008] A screen circuit board, used for being electrically connected to the liquid crystal screen, and provided with a first solder pad;

[0009] A backlight circuit board is used for electrical connection with the backlight assembly and is provided with a second solder pad.

[0010] A solid conductive tape is used for electrically connecting the screen circuit board and the backlight circuit board, and is bonded between the first soldering pad and the second soldering pad.

[0011] Furthermore, a plurality of first gold fingers are disposed in the first pad, a plurality of second gold fingers are disposed in the second pad, and each first gold finger is electrically connected to each second gold finger accordingly.

[0012] Furthermore, the length of the first golden finger is greater than the length of the second golden finger.

[0013] Furthermore, the length of the first golden finger is greater than the width of the second golden finger.

[0014] Furthermore, the screen circuit board is provided with a screen alignment mark next to the first solder pad, and the backlight circuit board is provided with a hollow alignment mark next to the second solder pad; the screen alignment mark overlaps with the hollow alignment mark and is exposed from the hollow alignment mark.

[0015] Furthermore, the screen alignment mark is a hollow alignment mark or a silk-screen alignment mark.

[0016] Furthermore, the circuit board assembly also includes an insulating film, which is attached to a surface of the backlight circuit board on a side facing away from the screen circuit board and covers the first soldering pad and the second soldering pad.

[0017] Furthermore, the screen circuit board is also provided with a third solder pad for electrically connecting to the liquid crystal screen, and a fourth solder pad for electrically connecting to the main control board of the display terminal, and the first solder pad and the third solder pad are respectively electrically connected to the fourth solder pad through the first routing inside the screen circuit board.

[0018] Furthermore, the backlight circuit board is also provided with a fifth pad for electrically connecting to the backlight assembly, and the second pad is electrically connected to the fifth pad via a second wiring inside the backlight circuit board.

[0019] A liquid crystal display module comprises a liquid crystal screen, a backlight assembly and the above-mentioned circuit board assembly, wherein the screen circuit board is electrically connected to the liquid crystal screen, and the backlight circuit board is electrically connected to the backlight assembly.

[0020] The utility model has the following beneficial effects: the circuit board assembly of the utility model uses the solid conductive tape to bond and fix between the first soldering pad of the screen circuit board and the second soldering pad of the backlight circuit board to form an electrical connection; the solid conductive tape is in a solid state before and after bonding and has no fluidity, so its height does not change much before and after bonding, which facilitates height control, reduces the risk of exceeding the height standard, and avoids the solid conductive tape interfering with the casing of the display terminal due to exceeding the height standard when assembling the display terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural schematic diagram of the circuit board assembly provided by the utility model.

[0022] Figure 2 for Figure 1 The AA cross-sectional structural diagram of the circuit board assembly shown.

[0023] Figure 3This is a schematic structural diagram of a screen circuit board in a circuit board assembly provided by the utility model.

[0024] Figure 4 The utility model provides a schematic structural diagram of a backlight circuit board in a circuit board assembly.

[0025] Figure 5 This is a schematic structural diagram of another circuit board assembly provided by the utility model. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments, examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0027] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Embodiment 1

[0030] like Figure 1 and 2As shown, a circuit board assembly is used for a liquid crystal display module, wherein the liquid crystal display module includes a liquid crystal screen and a backlight assembly; the circuit board assembly includes:

[0031] The screen circuit board 310 is used for being electrically connected to the liquid crystal screen and is provided with a first solder pad 311;

[0032] The backlight circuit board 320 is used to be electrically connected to the backlight assembly and is provided with a second solder pad 321.

[0033] The solid conductive tape 330 is used to electrically connect the screen circuit board 310 and the backlight circuit board 320 , and is bonded between the first soldering pad 311 and the second soldering pad 321 .

[0034] The circuit board assembly of the utility model uses the solid conductive tape 330 to bond and fix the first solder pad 311 of the screen circuit board 310 and the second solder pad 321 of the backlight circuit board 320 to form an electrical connection. Since the solid conductive tape 330 is in a solid state before and after bonding and has no fluidity, its height does not change much before and after bonding, which facilitates height control, reduces the risk of exceeding the height standard, and avoids the solid conductive tape 330 interfering with the casing of the display terminal due to exceeding the height standard when assembling the display terminal.

[0035] The solid conductive tape 330 includes a solid adhesive material and a conductive capsule doped in the solid adhesive material, wherein the conductive capsule contains conductive particles; after the first pad 311 of the screen circuit board 310 and the second pad 321 of the backlight circuit board 320 are relatively bonded and fixed by the solid conductive tape 330, a hot pressing head is used to perform hot pressing on the screen circuit board 310 and the backlight circuit board 320 in a direction perpendicular to the tape plane of the solid conductive tape 330, so as to crush the conductive capsule in the solid conductive tape 330. The conductive particles in the conductive capsule overflow and form an electrical connection channel in a direction perpendicular to the tape plane, so as to electrically connect the first pad 311 and the second pad 321 in the vertical direction.

[0036] The conductive particles may be, but are not limited to, metal particles, such as nano-gold powder or nano-silver powder.

[0037] A plurality of first gold fingers 31a are provided in the first pad 311, and a plurality of second gold fingers 32a are provided in the second pad 321. Each first gold finger 31a is electrically connected to each second gold finger 32a. In order to reserve a fitting tolerance, the length of the first gold finger 31a is greater than the length of the second gold finger 32a, and the length of the first gold finger 31a is greater than the width of the second gold finger 32a.

[0038] During bonding, even if there is a certain offset between the first pad 311 and the second pad 321 in the length direction and the width direction, the first gold fingers 31 a and the second gold fingers 32 a can be electrically connected in a one-to-one correspondence.

[0039] Preferably, the first golden finger 31 a is about 1 mm longer than the second golden finger 32 a in the length direction, and is about 0.5 mm wider than the second golden finger 32 a in the width direction.

[0040] At the same time, in order to improve the fitting accuracy, such as Figure 3 and 4 As shown, the screen circuit board 310 is provided with a screen alignment mark 314 next to the first solder pad 311 , and the backlight circuit board 320 is provided with a hollow alignment mark 323 next to the second solder pad 321 ; the screen alignment mark 314 overlaps with the hollow alignment mark 323 and is exposed from the hollow alignment mark 323 .

[0041] During bonding, the solid conductive tape 330 is first bonded to the second pad 321 of the backlight circuit board 320, and then a CCD camera is placed on one side of the backlight circuit board 320. The screen circuit board 310 is photographed and imaged by the CCD camera through the hollow alignment mark 323 on the backlight circuit board 320. Then, an alignment robot is used to drive the screen circuit board 310 to move relative to the backlight circuit board 320. When the CCD camera recognizes that the screen alignment mark 314 coincides with the hollow alignment mark 323, the alignment robot stops the movement of the screen circuit board 310 and bonds the first pad 311 of the screen circuit board 310 to the surface of the side of the solid conductive tape 330 facing away from the second pad 321. Finally, a hot press head is used to crush the conductive capsule in the solid conductive tape 330 so that the first pad 311 and the second pad 321 are electrically connected in the vertical direction.

[0042] In this embodiment, the screen alignment mark 314 can be, but is not limited to, a hollow alignment mark or a silk-screen alignment mark. The hollow alignment mark 323 and the screen alignment mark 314 are both cross marks, and alignment marks of other shapes can also be used.

[0043] like Figure 5 As shown, the circuit board assembly further includes an insulating film 340 , which is attached to a surface of the backlight circuit board 320 facing away from the screen circuit board 310 and covers the first solder pad 311 and the second solder pad 321 .

[0044] The insulating film 340 is mainly used to insulate and protect the first pad 311 and the second pad 321, and seal the first pad 311 and the second pad 321 to prevent external water vapor from invading the solid conductive tape 330. The insulating film 340 can be, but is not limited to, a PET film, a PI film, or a PVC film.

[0045] like Figure 3 and 4 As shown, the screen circuit board 310 is also provided with a third solder pad 312 for electrically connecting to the liquid crystal screen, and a fourth solder pad 313 for electrically connecting to the main control board of the display terminal, and the first solder pad 311 and the third solder pad 312 are electrically connected to the fourth solder pad 313 respectively through the first routing inside the screen circuit board 310.

[0046] The backlight circuit board 320 is further provided with a fifth pad 322 for electrically connecting to the backlight assembly, and the second pad 321 is electrically connected to the fifth pad 322 via a second wiring inside the backlight circuit board 320 . Embodiment 2

[0047] A liquid crystal display module includes a liquid crystal screen 100, a backlight assembly 200 and the above-mentioned circuit board assembly 300, wherein the screen circuit board 310 is electrically connected to the liquid crystal screen 100, and the backlight circuit board 320 is electrically connected to the backlight assembly 200.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the utility model rather than to limit them. Although the embodiments of the utility model are described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the embodiments of the utility model can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the embodiments of the utility model.

Claims

1. A circuit board assembly for a liquid crystal display module, wherein the liquid crystal display module comprises a liquid crystal screen and a backlight assembly; characterized in that: The circuit board assembly comprises: A screen circuit board, used for being electrically connected to the liquid crystal screen, and provided with a first solder pad; A backlight circuit board is used for electrical connection with the backlight assembly and is provided with a second solder pad. A solid conductive tape is used for electrically connecting the screen circuit board and the backlight circuit board, and is bonded between the first soldering pad and the second soldering pad.

2. The circuit board assembly according to claim 1, characterized in that: A plurality of first gold fingers are arranged in the first pad, a plurality of second gold fingers are arranged in the second pad, and each of the first gold fingers is electrically connected to each of the second gold fingers.

3. The circuit board assembly according to claim 2, characterized in that: The length of the first golden finger is greater than the length of the second golden finger.

4. The circuit board assembly according to claim 2 or 3, characterized in that: The length of the first golden finger is greater than the width of the second golden finger.

5. The circuit board assembly according to claim 1, characterized in that: The screen circuit board is provided with a screen alignment mark next to the first pad, and the backlight circuit board is provided with a hollow alignment mark next to the second pad; the screen alignment mark overlaps with the hollow alignment mark and is exposed from the hollow alignment mark.

6. The circuit board assembly according to claim 5, characterized in that: The screen alignment mark is a hollow alignment mark or a silk-screen alignment mark.

7. The circuit board assembly according to claim 1, characterized in that: The circuit board assembly further includes an insulating film, which is attached to a surface of the backlight circuit board on a side facing away from the screen circuit board and covers the first soldering pad and the second soldering pad.

8. The circuit board assembly according to claim 1, characterized in that: The screen circuit board is also provided with a third pad for electrically connecting to the liquid crystal screen, and a fourth pad for electrically connecting to the main control board of the display terminal. The first pad and the third pad are electrically connected to the fourth pad respectively through the first routing inside the screen circuit board.

9. The circuit board assembly according to claim 1, characterized in that: The backlight circuit board is also provided with a fifth pad for electrically connecting to the backlight assembly, and the second pad is electrically connected to the fifth pad via a second wiring inside the backlight circuit board.

10. A liquid crystal display module, characterized in that: It comprises a liquid crystal screen, a backlight assembly and the circuit board assembly as claimed in claim 1, wherein the screen circuit board is electrically connected to the liquid crystal screen, and the backlight circuit board is electrically connected to the backlight assembly.

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