A Ceramic Filter with CTE Compensation

Abstract

The present invention discloses a ceramic filter with CTE compensation, comprising a filter body, wherein an input terminal and an output terminal are arranged on a signal transmission surface of the filter body, in order to avoid connection with a PCB board and effectively reduce the use cost, the buffering performance when connected with a communication system board can be improved, and the functions of supporting the filter, connecting the signal to the ground and compensating for the CTE inconsistency between the ceramic and the communication system board when the PCB board is used can be retained. The ceramic filter with CTE compensation described in the present invention also comprises a plurality of first elastic metal pads for connecting the communication system board; the first elastic metal pads are discretely arranged on the signal transmission surface and staggered with the input terminal and the output terminal; the thermal expansion coefficient of the first elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a dielectric waveguide filter which can be directly mounted on a communication system board and has CTE (ie coefficient of thermal expansion) compensation. Background Art

[0002] With the widespread application of 5G technology, the demand for 5G base stations has gradually increased, and ceramic dielectric filters have gradually become an important component used by various equipment manufacturers. Among them, single-layer ceramic dielectric filters and double-layer ceramic dielectric filters are the main solutions.

[0003] Single-layer ceramic dielectric filters are usually assembled with a supporting PCB board and mounted on the communication system board for use. When used in a single layer, the added PCB board plays the role of supporting the ceramic dielectric filter, connecting the signal ground, and compensating for the CTE inconsistency between the ceramic and the communication system board. Due to the single-layer structure of the ceramic dielectric filter, its length and width will increase significantly compared to the multi-layer structure, and the corresponding PCB board size will increase, and the cost will rise.

[0004] The double-layer ceramic dielectric filter is usually assembled with a PCB board with low-pass performance and mounted on the communication system board for use. When used in double layers, the added PCB board plays the role of supporting the ceramic dielectric filter, connecting the signal ground, compensating for the CTE inconsistency between the ceramic and the communication system board, and low-pass filtering. The length, width and area of ​​the double-layer ceramic dielectric filter are relatively small compared to a single-layer product. However, due to the requirement for low-pass performance of the PCB board, this PCB board requires a higher-performance RF board, which increases the cost significantly.

[0005] At present, the above two solutions in the industry are Figure 1 As shown, an additional PCB board 3 is required. The length and width of the corresponding PCB board 3 are generally almost the same as those of the ceramic dielectric filter 1. The application of the PCB board 3 in realizing the connection between the ceramic dielectric filter 1 and the communication system board leads to a large increase in the use cost. And because the PCB board 3 has a certain rigidity, the buffering performance is poor when connected to the communication system board. Moreover, in the above two schemes, the input and output ends of the ceramic dielectric filter 1 use solid solderable copper pins 2 with a diameter ranging from 0.5 to 3 mm to transmit signals. When connecting to the communication system board, due to the high rigidity of the copper pin 2, the buffering performance is even worse when connected to the communication system board. Summary of the invention

[0006] In order to overcome the shortcomings of the prior art, the technical problem solved by the present invention is to propose a ceramic filter with CTE compensation, which not only eliminates the need to use a PCB board to achieve connection with a communication system board, thereby helping to reduce the cost of use, but also retains the functions of supporting the filter, connecting the signal to the ground, and compensating for the inconsistency of CTE between the ceramic and the communication system board when using the PCB board, and can also improve the buffering performance when connected to the communication system board.

[0007] In order to solve the above technical problems, the technical solutions adopted by the present invention are specifically as follows:

[0008] A ceramic filter with CTE compensation includes a filter body, wherein an input terminal and an output terminal are arranged on a signal transmission surface of the filter body. In order to avoid connection with a PCB board and effectively reduce the use cost, the buffering performance when connected with a communication system board can be improved, and the functions of supporting the filter, connecting the signal to the ground, and compensating for the inconsistency of CTE between the ceramic and the communication system board when the PCB board is used can be retained. The ceramic filter with CTE compensation described in the present invention also includes a plurality of first elastic metal pads for connecting to the communication system board; the first elastic metal pads are discretely arranged on the signal transmission surface and staggered with the input terminal and the output terminal; the thermal expansion coefficient of the first elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board.

[0009] Furthermore, a second elastic metal pad is provided on the input end and the output end; the thermal expansion coefficient of the second elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board.

[0010] Furthermore, the first elastic metal pad is a first spring structure.

[0011] Preferably, the first spring structure includes a first welding portion for connecting to the signal transmission surface, a second welding portion for connecting to a communication system board, and a first buffer deformation portion for connecting the first welding portion and the second welding portion.

[0012] More preferably, the longitudinal section of the first elastic sheet structure is a rectangular structure with a bend.

[0013] More preferably, the first spring sheet structure has a length of 1 to 4 mm, a width of 1 to 4 mm, and a height of 1 to 3 mm.

[0014] More preferably, the first elastic sheet structure has a length of 2.5 mm, a width of 1.5 mm, and a height of 1.1 mm.

[0015] Alternatively, the cross section of the first elastic sheet structure is an arc-shaped structure with a bend.

[0016] Preferably, the arc-shaped structure is a superior arc-shaped structure.

[0017] Furthermore, the second elastic metal pad is a second spring structure.

[0018] Preferably, the second spring structure includes a third welding portion for connecting the input end and the output end, a fourth welding portion for connecting the communication system board, and a second buffer deformation portion for connecting the third welding portion and the fourth welding portion.

[0019] More preferably, the longitudinal section of the second elastic sheet structure is a convex structure with a bend.

[0020] More preferably, the second elastic sheet structure has a length of 1 to 3 mm, a width of 1 to 3 mm, and a height of 1 to 3 mm.

[0021] More preferably, the second spring structure has a length of 2 mm, a width of 2 mm, and a height of 1.3 mm. Further, the first elastic metal pads are evenly arranged on the signal transmission surface.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The ceramic filter with CTE compensation of the present invention, when in use, uses a plurality of first elastic metal pads to connect with the communication system board. Since the first elastic metal pads are elastic, the buffering performance when connected with the communication system board can be effectively improved. Moreover, a plurality of first elastic metal pads are discretely arranged on the signal transmission surface to replace the existing whole PCB board to connect with the communication system board, thereby achieving the purpose of helping to reduce the use cost. Moreover, since the first elastic metal pads are discretely designed, there are gaps between adjacent first elastic metal pads. When connecting with the communication system board, these gaps are filled with air. Compared with the existing use of the whole PCB board, the buffering performance when connected with the communication system board is further improved.

[0024] 2. Since the first elastic metal pad is arranged on the filter body, the filter body can be supported when in use, and the first elastic metal pad can be used for grounding operation, and the thermal expansion coefficient of the first elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board, the CTE inconsistency between the ceramic and the communication system board can be compensated, thereby achieving the purpose of eliminating the use of the PCB board while retaining the function of using the PCB board.

[0025] 3. A second elastic metal pad is set at the input and output ends of the filter body to replace the existing copper pin as the signal transmission end, which has greater elasticity, so the buffering performance is better when connected to the communication system board.

[0026] 4. When the first elastic metal pad and the second elastic metal are respectively a first spring structure and a second spring structure, the structures of the second elastic metal pad and the first elastic metal pad can be made simpler, which helps to further reduce the use cost.

[0027] 5. The cross section of the first spring sheet structure is an arc-shaped structure with a bend, so that the signal line can be routed through the hollowed-out part of the first spring sheet structure, and the electrical effect is better. The arc-shaped structure is an arc-shaped structure, and the installation stability with the system connection board is higher.

[0028] 6. The longitudinal section of the first spring sheet structure is a rectangular structure with a bend, so that the first elastic metal pad is a hollow structure, which simplifies the structure of the first elastic metal pad, not only helps to improve the elasticity of the first elastic metal pad, but also further reduces the use cost. Moreover, compared with the first spring sheet structure with an arc-shaped cross section, the first spring sheet structure with a rectangular structure with a bend in the longitudinal section has better elasticity, so the effect of buffering stress is better.

[0029] 7. The first elastic metal pads are evenly arranged on the signal transmission surface, thereby helping to improve the installation stability between the ceramic filter with CTE compensation of the present invention and the communication system board.

[0030] 8. The longitudinal section of the second spring structure is a convex structure with a bend, so that the second elastic metal pad is a hollow structure, which simplifies the structure of the second elastic metal pad, not only helps to improve the elasticity of the second elastic metal pad, but also further reduces the cost of use.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of an existing ceramic filter;

[0033] Figure 2 The structure of the ceramic filter with CTE compensation of the present invention is a preferred embodiment of the present invention. Figure 1 ;

[0034] Figure 3 The structure of the ceramic filter with CTE compensation of the present invention is a preferred embodiment of the present invention. Figure 2 ;

[0035] Figure 4 The structure of the ceramic filter with CTE compensation of the present invention is a preferred embodiment of the present invention. Figure 3 .

[0036] Figure 5 is a schematic structural diagram of a second elastic metal pad of the present invention;

[0037] Figure 6 It is a schematic diagram of a first structure of the first elastic metal pad of the present invention;

[0038] Figure 7 It is a schematic diagram of the second structure of the first elastic metal pad of the present invention.

[0039] in, Figure 1 The reference numerals are described as follows:

[0040] 1. Ceramic dielectric filter; 2. Copper pins; 3. PCB board.

[0041] Figures 2 to 7 The reference numerals are described as follows:

[0042] 1. Filter body; 11. Input end; 12. Output end; 13. Transmission surface; 2. Second elastic metal pad; 21. Third welding part; 22. Fourth welding part; 23. Second buffer deformation part; 24. Bend; 25. Convex structure; 3. First elastic metal pad; 31. First welding part; 32. Second welding part; 33. First buffer deformation part; 34. Bend; 35. Rectangular structure; 36. Bend; 37. Arc structure. DETAILED DESCRIPTION

[0043] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments:

[0044] Embodiment 1

[0045] like Figure 2 and Figure 6What is shown is a first embodiment of the ceramic filter with CTE compensation described in the present invention, comprising a filter body 1, wherein an input terminal 11 and an output terminal 12 are arranged on a signal transmission surface 13 of the filter body 1. In order to avoid the need to connect a PCB board and effectively reduce the use cost, the buffering performance when connected to a communication system board can also be improved, while retaining the functions of supporting the filter, connecting the signal to the ground, and compensating for the inconsistency of CTE between the ceramic and the communication system board when using the PCB board. The ceramic filter with CTE compensation described in the present invention also comprises a plurality of first elastic metal pads 3 for connecting to the communication system board; the first elastic metal pads 3 are discretely arranged on the signal transmission surface 13 and staggered with the input terminal 11 and the output terminal 12; the thermal expansion coefficient of the first elastic metal pad 3 is equivalent to the thermal expansion coefficient of the PCB board.

[0046] When in use, a plurality of first elastic metal pads 3 are used to connect with the communication system board. Since the first elastic metal pads 3 are elastic, the buffering performance when connected with the communication system board can be effectively improved. Moreover, a plurality of first elastic metal pads 3 are discretely arranged on the signal transmission surface to replace the existing whole PCB board to connect with the communication system board, thereby achieving the purpose of helping to reduce the use cost. Moreover, since the first elastic metal pads 3 are discretely designed, there are gaps between adjacent first elastic metal pads 3. When connecting with the communication system board, these gaps are filled with air. Compared with the existing use of the whole PCB board, the buffering performance when connected with the communication system board is further improved.

[0047] Since the first elastic metal pad 3 is arranged on the filter body 1, the filter body 1 can be supported when in use, and the first elastic metal pad 3 can be used for grounding operation, and the thermal expansion coefficient of the first elastic metal pad 3 is equivalent to the thermal expansion coefficient of the PCB board, the CTE inconsistency between the ceramic and the communication system board can be compensated, thereby achieving the purpose of eliminating the use of the PCB board while retaining the function of using the PCB board.

[0048] As an improvement of this embodiment, the first elastic metal pad 3 is a first spring structure. The first spring structure includes a first welding portion 31 for connecting the signal transmission surface 13, a second welding portion 32 for connecting the communication system board, and a first buffer deformation portion 33 for connecting the first welding portion 31 and the second welding portion 32. Figure 6 As shown, it is more preferred that the longitudinal section of the first spring structure is a rectangular structure 35 with a bend 34, so that the first elastic metal pad 3 is a hollow structure, which simplifies the structure of the first elastic metal pad 3, not only helps to improve the elasticity of the first elastic metal pad 3, but also further reduces the cost of use.

[0049] In this embodiment, the length of the first spring sheet structure is 1-4 mm, the width is 1-4 mm, and the height is 1-3 mm. Preferably, the length of the first spring sheet structure is 2.5 mm, the width is 1.5 mm, and the height is 1.1 mm. The first elastic metal pad 3 is evenly arranged on the signal transmission surface 13. This helps to improve the installation stability between the ceramic filter with CTE compensation of the present invention and the communication system board.

[0050] Embodiment 2

[0051] Figure 7 The second embodiment of the ceramic filter with CTE compensation described in the present invention is shown. The only difference between the second embodiment and the first embodiment is that the cross section of the first spring sheet structure is an arc structure 37 with a bend 36, so that the signal line can be routed from the hollowed-out part of the first spring sheet structure, and the electrical effect is better. However, compared with the first spring sheet structure with a rectangular structure 35 with a bend 34 in the longitudinal section, the first spring sheet structure with an arc structure 37 with a bend 34 in the cross section has slightly poor elasticity, so the effect of buffering stress is poor, but the installation stability with the communication system board is higher. In this embodiment, the arc structure is a superior arc structure, and the arc length of the superior arc structure is 3 / 4 of a circle. Specifically, the inner diameter of the arc structure is 5.6 mm, the outer diameter is 7.5 mm, and the height is 1.1 mm.

[0052] Embodiment 3

[0053] Figure 3 The third embodiment of the ceramic filter with CTE compensation described in the present invention is shown. The only difference between the third embodiment and the first embodiment is that a second elastic metal pad 2 is also provided on the input end 11 and the output end 12; the thermal expansion coefficient of the second elastic metal pad 2 is equivalent to the thermal expansion coefficient of the PCB board.

[0054] The second elastic metal pad 2 is arranged at the input end 11 and the output end 12 of the filter body 1 to replace the existing copper pin as the signal transmission end, which has greater elasticity and thus has better buffering performance when connected to the communication system board.

[0055] As a further improvement of this embodiment, Figure 5As shown, the second elastic metal pad 2 is a second spring structure. The second spring structure includes a third welding portion 21 for connecting the input end 11 and the output end 12, a fourth welding portion 22 for connecting the communication system board, and a second buffer deformation portion 23 for connecting the third welding portion 21 and the fourth welding portion 22. More preferably, the longitudinal section of the second spring structure is a convex structure 25 with a bend 24. The longitudinal section of the second spring structure is a convex structure 25 with a bend 24, so that the second elastic metal pad 2 is a hollow structure, which simplifies the structure of the second elastic metal pad 2, not only helps to improve the elasticity of the second elastic metal pad 2, but also further reduces the use cost. In this embodiment, the length of the second spring structure is 1 to 3 mm, the width is 1 to 3 mm, and the height is 1 to 3 mm. Preferably, the length of the second spring structure is 2 mm, the width is 2 mm, and the height is 1.3 mm.

[0056] Embodiment 4

[0057] Figure 4 The fourth embodiment of the ceramic filter with CTE compensation described in the present invention is shown, and the only difference between it and the second embodiment mentioned above is that a second elastic metal pad 2 is also provided on the input end 11 and the output end 12; the thermal expansion coefficient of the second elastic metal pad 2 is equivalent to the thermal expansion coefficient of the PCB board.

[0058] The second elastic metal pad 2 is arranged at the input end 11 and the output end 12 of the filter body 1 to replace the existing copper pin as the signal transmission end, which has greater elasticity and thus has better buffering performance when connected to the communication system board.

[0059] As a further improvement of this embodiment, Figure 5 As shown, the second elastic metal pad 2 is a second spring structure. The second spring structure includes a third welding portion 21 for connecting the input end and the output end, a fourth welding portion 22 for connecting the communication system board, and a second buffer deformation portion 23 for connecting the third welding portion 21 and the fourth welding portion 22. More preferably, the longitudinal section of the second spring structure is a convex structure 25 with a bend 24. The longitudinal section of the second spring structure is a convex structure 25 with a bend 24, so that the second elastic metal pad 2 is a hollow structure, which simplifies the structure of the second elastic metal pad 2, not only helps to improve the elasticity of the second elastic metal pad 2, but also further reduces the cost of use. In this embodiment, the length of the second spring structure is 1 to 3 mm, the width is 1 to 3 mm, and the height is 1 to 3 mm. Preferably, the length of the second spring structure is 2 mm, the width is 2 mm, and the height is 1.3 mm.

[0060] It should be noted that the "several" mentioned in the present invention specifically refers to at least two, and the user can set the specific number of the first elastic metal pads according to the actual use needs, and should not be limited to the number shown in the drawings of the present invention. In addition, the size of each of the first elastic metal pads is smaller than that of a single PCB board.

[0061] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0062] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A ceramic filter with CTE compensation, comprising a filter body, wherein an input end and an output end are provided on a signal transmission surface of the filter body, wherein: It also includes a plurality of first elastic metal pads for connecting the communication system board; the first elastic metal pads are discretely arranged on the signal transmission surface and staggered with the input end and the output end; the thermal expansion coefficient of the first elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board; A second elastic metal pad is also provided on the input end and the output end; the thermal expansion coefficient of the second elastic metal pad is equivalent to the thermal expansion coefficient of the PCB board; The first elastic metal pad is a first spring structure; The first spring structure includes a first welding portion for connecting the signal transmission surface, a second welding portion for connecting the communication system board, and a first buffer deformation portion for connecting the first welding portion and the second welding portion; The longitudinal section of the first elastic sheet structure is a rectangular structure with a bend.

2. The ceramic filter with CTE compensation according to claim 1, characterized in that: The first spring sheet structure has a length of 1 to 4 mm, a width of 1 to 4 mm, and a height of 1 to 3 mm.

3. The ceramic filter with CTE compensation according to claim 2, characterized in that: The first spring sheet structure has a length of 2.5 mm, a width of 1.5 mm, and a height of 1.1 mm.

4. The ceramic filter with CTE compensation according to claim 1, characterized in that: The second elastic metal pad is a second spring structure.

5. The ceramic filter with CTE compensation according to claim 4, characterized in that: The second spring sheet structure includes a third welding portion for connecting the input end and the output end, a fourth welding portion for connecting the communication system board, and a second buffer deformation portion for connecting the third welding portion and the fourth welding portion.

6. The ceramic filter with CTE compensation according to claim 5, characterized in that: The longitudinal section of the second elastic sheet structure is a convex structure with a bend.

7. The ceramic filter with CTE compensation according to claim 6, characterized in that: The second spring sheet structure has a length of 1 to 3 mm, a width of 1 to 3 mm, and a height of 1 to 3 mm.

8. The ceramic filter with CTE compensation according to claim 6, characterized in that: The second spring structure has a length of 2 mm, a width of 2 mm, and a height of 1.3 mm.

9. The ceramic filter with CTE compensation according to any one of claims 1 to 8, characterized in that: The first elastic metal pads are evenly arranged on the signal transmission surface.

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