Coupler

Abstract

This application relates to a coupler comprising a substrate, a first stacked spiral inductor disposed within the substrate, and a second stacked spiral inductor disposed within the substrate. The first stacked spiral inductor includes a first spiral coil and a second spiral coil stacked together. The second stacked spiral inductor is coupled to the first stacked spiral inductor. The second stacked spiral inductor includes a third spiral coil and a fourth spiral coil stacked together. This application achieves energy transfer through electromagnetic coupling between the first and second stacked spiral inductors, thereby forming a coupler. This application can integrate the inductors into a single ceramic substrate using a low-temperature co-fired ceramic process, forming a monolithic structure, which not only significantly reduces the size of the coupler but also improves its integration density, environmental adaptability, and consistency.

Description

Technical Field

[0001] This application belongs to the field of microwave system technology, and in particular relates to a coupler. Background Technology

[0002] Currently, in microwave technology, the microwave coupler is one of the main passive microwave components. It is an important component used in microwave systems to separate or combine signals of various frequencies. As electronic systems continue to develop towards miniaturization, lightweighting, and high performance, electronic systems are placing higher demands on the size and power performance of microwave couplers.

[0003] Traditional couplers are made by winding coils on a magnetic core. Such products have problems such as large size, poor environmental adaptability, high cost and low consistency, which cannot meet the requirements of modern technology for small size, low cost, high performance and high consistency. Summary of the Invention

[0004] The purpose of this application is to provide a coupler that addresses the problems of traditional couplers, such as large size, poor environmental adaptability, high cost, and low consistency.

[0005] A first aspect of this application provides a coupler, comprising: a substrate; a first stacked spiral inductor disposed within the substrate, the first stacked spiral inductor including a first spiral coil and a second spiral coil stacked together, the outer port of the first spiral coil being a first port of the coupler, the substrate being connected between the inner port of the first spiral coil and the inner port of the second spiral coil through a first through hole, the outer port of the second spiral coil being a second port of the coupler; and a second stacked spiral inductor disposed within the substrate, the second stacked spiral inductor being coupled to the first stacked spiral inductor, the second stacked spiral inductor including a third spiral coil and a fourth spiral coil stacked together, the outer port of the third spiral coil being a third port of the coupler, the substrate being connected between the inner port of the third spiral coil and the inner port of the fourth spiral coil through a first through hole, the outer port of the fourth spiral coil being a fourth port of the coupler.

[0006] In one embodiment, the first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil are stacked sequentially from top to bottom within the substrate.

[0007] In one embodiment, the pattern of the second spiral coil is obtained by rotating the pattern of the first spiral coil by 180° along the height direction; the pattern of the third spiral coil is obtained by rotating the pattern of the second spiral coil by 180° along the length direction; and the pattern of the fourth spiral coil is obtained by rotating the pattern of the third spiral coil by 180° along the height direction.

[0008] In one embodiment, the first port is disposed on the front surface of the substrate, and the length direction is parallel to the front surface.

[0009] In one embodiment, the first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil are all double-layer spiral coils, and each of the first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil is composed of two parallel 1 / 8 wavelength planar coils.

[0010] In one embodiment, the linewidth of the 1 / 8 wavelength planar coil is 100μm to 130μm; the thickness of the 1 / 8 wavelength planar coil is 7μm to 13μm.

[0011] In one embodiment, the spacing between the first stacked spiral inductor and the second stacked spiral inductor is 0.65 mm to 0.75 mm; the spacing between the spiral coils in the same spiral inductor is 100 μm to 135 μm; and the spacing between the 1 / 8 wavelength planar coils in the same spiral coil is 5 μm to 15 μm.

[0012] In one embodiment, the system further includes a first shielding layer and a second shielding layer disposed within the substrate. Both the first shielding layer and the second shielding layer are parallel to the first stacked spiral inductor and the second stacked spiral inductor, respectively. The first shielding layer is disposed above the first stacked spiral inductor, and the second shielding layer is disposed below the second stacked spiral inductor.

[0013] In one embodiment, the outer surface of the substrate is further provided with a first external electrode, a second external electrode, a third external electrode and a fourth external electrode, wherein the first external electrode is connected to the first port, the second external electrode is connected to the second port, the third external electrode is connected to the third port and the fourth external electrode is connected to the fourth port.

[0014] In one embodiment, a grounding shield layer is further provided on the outer surface of the substrate, and the grounding shield layer is used to connect to the ground terminal.

[0015] The beneficial effects of this application embodiment compared with the prior art are as follows: This application achieves energy transfer through electromagnetic coupling between the first stacked spiral inductor and the second stacked spiral inductor, thereby forming a coupler. This application can use the Low Temperature Co-fired Ceramic (LTCC) process to integrate the inductor into a ceramic substrate, forming a monolithic structure, which can not only greatly reduce the size of the coupler, but also improve the integration, environmental adaptability and consistency of the coupler. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the coupler provided in the first embodiment of this application;

[0017] Figure 2 A schematic diagram of the pattern of the first spiral coil provided in the first embodiment of this application;

[0018] Figure 3 A schematic diagram of the pattern of the second spiral coil provided in the first embodiment of this application;

[0019] Figure 4 A schematic diagram of the third spiral coil provided in the first embodiment of this application;

[0020] Figure 5 The equivalent circuit diagram of the spiral inductor provided in the first embodiment of this application;

[0021] Figure 6 This is a schematic diagram of the structure of a coupler provided in another embodiment of this application;

[0022] Figure 7 This is a schematic diagram of the external shape of the coupler provided in the first embodiment of this application.

[0023] The above figures illustrate the following: 100, substrate; 200, first multilayer spiral inductor; 210, first spiral coil; 211, first 1 / 8 wavelength planar coil; 212, second 1 / 8 wavelength planar coil; 220, second spiral coil; 221, third 1 / 8 wavelength planar coil; 222, fourth 1 / 8 wavelength planar coil; 230, first through-hole; 300, second multilayer spiral inductor; 310, third spiral coil; 311, fifth 1 / 8 wavelength planar coil; 312, sixth 1 / 8 wavelength planar coil; 320, fourth spiral coil; 321, seventh 1 / 8 wavelength planar coil; 322, eighth 1 / 8 wavelength planar coil; 330, second through-hole; 410, first shielding layer; 420, second shielding layer; 510, first external electrode; 520, second external electrode; 530, third external electrode; 540, fourth external electrode; 550, grounding shielding layer. Detailed Implementation

[0024] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0025] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0026] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0028] Figure 1 A schematic diagram of the coupler provided in the first embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below:

[0029] A coupler includes: a substrate 100, a first stacked spiral inductor 200, and a second stacked spiral inductor 300.

[0030] The substrate 100 can be a ceramic substrate. In one example, the length, width, and height of the substrate 100 are 9.0 mm, 5.0 mm, and 1.5 mm, respectively. The substrate 100 is made of low-temperature co-fired ceramic powder with a sintering temperature ≤900℃, a dielectric constant of 6 to 9, and a dielectric loss factor of tanα ≤0.002. In one example, the sintering temperature is 855℃, the dielectric constant of the low-temperature co-fired ceramic powder is 7.5, and the dielectric loss factor is tanα 0.001. The first stacked spiral inductor 200 is disposed within the substrate 100. The first stacked spiral inductor 200 includes a first spiral coil 210 and a second spiral coil 220 stacked and parallel to each other. The outer ring port of the first spiral coil 210 is the first port A of the coupler. The substrate 100 is connected between the inner ring port of the first spiral coil 210 and the inner ring port of the second spiral coil 220 through a first through hole 230. The outer ring port of the second spiral coil 220 is the second port B of the coupler. A second stacked spiral inductor 300 is disposed within the substrate 100 and is coupled to the first stacked spiral inductor 200. The second stacked spiral inductor 300 includes a third spiral coil 310 and a fourth spiral coil 320 stacked and parallel to each other. The outer port of the third spiral coil 310 is the third port C of the coupler. The substrate 100 is connected between the inner ports of the third spiral coil 310 and the inner ports of the fourth spiral coil 320 through a second through-hole 330. The outer port of the fourth spiral coil 320 is the fourth port D of the coupler. In one example, the first stacked spiral inductor 200 and the second stacked spiral inductor 300 are made of low-temperature silver paste with a sintering temperature ≤900℃ and a silver content of 85% ± 10%. In one example, the sintering temperature is 700℃ and the silver content is 85%. The inner walls of the first through-hole 230 and the second through-hole 330 are also covered with silver paste for connecting the corresponding spiral coils.

[0031] In this embodiment, energy transfer is achieved through electromagnetic coupling between the first stacked spiral inductor 200 and the second stacked spiral inductor 300, forming a coupler. Dividing a single stacked spiral inductor into two spiral coils widens the operating frequency range of the coupler, allowing it to be used for coupling low-frequency signals. The operating frequency of the coupler in this embodiment can be from 10MHz to 100MHz.

[0032] In this embodiment, the first spiral coil 210, the second spiral coil 220, the third spiral coil 310, and the fourth spiral coil 320 are stacked sequentially from top to bottom within the substrate 100. The coupler in this embodiment can be manufactured using a low-temperature co-fired ceramic (LTCC) process, stacking layers sequentially from top to bottom to integrate the inductor within a single substrate 100, forming a monolithic structure. This not only significantly reduces the size of the coupler but also improves its integration density, environmental adaptability, and consistency.

[0033] The pattern of the first spiral coil 210 is as follows: Figure 2 As shown, the pattern of the second spiral coil 220 is as follows: Figure 3 As shown, the pattern of the third spiral coil 310 is as follows: Figure 4 As shown, in this embodiment, the pattern of the second spiral coil 220 is obtained by rotating the pattern of the first spiral coil 210 by 180° along the height direction (Z-axis); the pattern of the third spiral coil 310 is obtained by rotating the pattern of the second spiral coil 220 by 180° along the length direction (Y-axis); and the pattern of the fourth spiral coil 320 is obtained by rotating the pattern of the third spiral coil 310 by 180° along the height direction.

[0034] By using symmetrical coil patterns, the number of stencils required for the coupler forming process can be reduced. In this embodiment, four spiral coils can be made using only one stencil, simplifying the forming process.

[0035] In one example, the equivalent circuit diagram of the first stacked spiral inductor 200 and the second stacked spiral inductor 300 is as follows: Figure 5 As shown, when the first port A is the input terminal, the second port B is the through terminal, the third port C is the coupling terminal, and the fourth port D is the isolation terminal; when the second port B is the input terminal, the first port A is the through terminal, the third port C is the isolation terminal, and the fourth port D is the coupling terminal; when the third port C is the input terminal, the fourth port D is the through terminal, the first port A is the coupling terminal, and the second port B is the isolation terminal; when the fourth port D is the input terminal, the third port C is the through terminal, the second port B is the coupling terminal, and the first port A is the isolation terminal. Because the pattern structures of the first spiral coil 210, the second spiral coil 220, the third spiral coil 310, and the fourth spiral coil 320 are symmetrical, each port can be used as an input terminal, and the type of each port changes accordingly when the input terminal changes.

[0036] In this embodiment, the first port A is disposed on the front surface of the substrate 100, with its length direction parallel to the front surface and parallel to the first stacked spiral inductor 200 and the second stacked spiral inductor 300, and its height direction parallel to the front surface and perpendicular to the length direction.

[0037] It should be noted that when the first port A is located on the front surface of the substrate 100, since the pattern of the second spiral coil 220 is obtained by rotating the pattern of the first spiral coil 210 by 180° along the height direction, the second port B is therefore located on the rear surface of the substrate 100. Since the pattern of the third spiral coil 310 is obtained by rotating the pattern of the second spiral coil 220 by 180° along the length direction, the third port C is correspondingly located on the front surface of the substrate 100, and the fourth port D is correspondingly located on the rear surface of the substrate 100.

[0038] In this embodiment, the first spiral coil 210, the second spiral coil 220, the third spiral coil 310 and the fourth spiral coil 320 are all double-layer spiral coils, and each of the first spiral coil 210, the second spiral coil 220, the third spiral coil 310 and the fourth spiral coil 320 is composed of two parallel 1 / 8 wavelength planar coils.

[0039] By using two layers of 1 / 8 wavelength planar coils connected in parallel to form a single spiral coil, the power capacity of the coupler can be greatly increased with relatively low manufacturing difficulty, and the power capacity of the coupler can exceed 50W.

[0040] Specifically, such as Figure 1 As shown, the first spiral coil 210 includes a first 1 / 8 wavelength planar coil 211 and a second 1 / 8 wavelength planar coil 212; the second spiral coil 220 includes a third 1 / 8 wavelength planar coil 221 and a fourth 1 / 8 wavelength planar coil 222; the third spiral coil 310 includes a fifth 1 / 8 wavelength planar coil 311 and a sixth 1 / 8 wavelength planar coil 312; and the fourth spiral coil 320 includes a seventh 1 / 8 wavelength planar coil 321 and an eighth 1 / 8 wavelength planar coil 322.

[0041] In this embodiment, the linewidth of each 1 / 8 wavelength planar coil is 100μm to 130μm. The thickness of each 1 / 8 wavelength planar coil is 7μm to 13μm. The spacing between the first stacked spiral inductor 200 and the second stacked spiral inductor 300 is 0.65mm to 0.75mm; specifically, the spacing between the fourth 1 / 8 wavelength planar coil 222 and the fifth 1 / 8 wavelength planar coil 311 is 0.65mm to 0.75mm. The spacing between the spiral coils in the same spiral inductor is 100μm to 135μm. For example, the spacing between the first spiral coil 210 and the second spiral coil 220 is 100μm to 135μm, that is, the spacing between the second 1 / 8 wavelength planar coil 212 and the third 1 / 8 wavelength planar coil 221 is 100μm to 135μm. The spacing between the 1 / 8 wavelength planar coils in the same spiral coil is 5μm to 15μm. For example, the spacing between the first 1 / 8 wavelength planar coil 211 and the second 1 / 8 wavelength planar coil 212 is 5μm to 15μm.

[0042] In one example, the linewidth of each 1 / 8 wavelength planar coil is 115 μm, the thickness of each 1 / 8 wavelength planar coil is 10 μm, the spacing between the first stacked spiral inductor 200 and the second stacked spiral inductor 300 is 0.7 mm, the spacing between the spiral coils within the same spiral inductor is 120 μm, and the spacing between the 1 / 8 wavelength planar coils within the same spiral coil is 10 μm. The coupler operates at a frequency of 27 MHz, with a mainline insertion loss ≤0.1 dB, a coupling coefficient of 30 ± 3 dB, a phase balance ≤6°, a standing wave ratio ≤1.3, and a directivity ≥15 dB.

[0043] like Figure 6 As shown, in another embodiment, a first shielding layer 410 and a second shielding layer 420 are also disposed within the substrate 100. Both the first shielding layer 410 and the second shielding layer 420 are parallel to the first stacked spiral inductor 200 and the second stacked spiral inductor 300. The first shielding layer 410 is disposed above the first stacked spiral inductor 200 and the second stacked spiral inductor 300, and the second shielding layer 420 is disposed below the second stacked spiral inductor 300.

[0044] Adding a first shielding layer 410 and a second shielding layer 420 inside the product can effectively increase the product's directionality and coupling, and avoid external electromagnetic interference.

[0045] like Figure 7 As shown, in this embodiment, the outer surface of the substrate 100 is further provided with a first external electrode 510, a second external electrode 520, a third external electrode 530 and a fourth external electrode 540. The first external electrode 510 is connected to the first port A, the second external electrode 520 is connected to the second port B, the third external electrode 530 is connected to the third port C, and the fourth external electrode 540 is connected to the fourth port D.

[0046] The first external electrode 510, the second external electrode 520, the third external electrode 530, and the fourth external electrode 540 can be used to connect to an external circuit by soldering.

[0047] In another embodiment, the linewidth of each 1 / 8 wavelength planar coil at each outer coil port is 250 μm to 500 μm. A larger linewidth ensures reliability when connected to the corresponding external electrode. In one example, the linewidth of each 1 / 8 wavelength planar coil at each outer coil port is 350 μm.

[0048] In this embodiment, a grounding shielding layer 550 is further provided on the outer surface of the substrate 100. The grounding shielding layer 550 is used to connect to the ground terminal. The grounding shielding layer 550 is used to further shield external electromagnetic signals.

[0049] In this embodiment, the first external electrode 510, the second external electrode 520, the third external electrode 530, the fourth external electrode 540, and the grounding shielding layer 550 are all composed of three layers of metal paste. The innermost layer is a silver layer with a silver content of 60% ± 20% and a sintering temperature of ≤800℃. The middle layer is a nickel layer, and the outermost layer is a tin layer. By setting three layers of metal paste, the reliability of the first external electrode 510, the second external electrode 520, the third external electrode 530, the fourth external electrode 540, and the grounding shielding layer 550 during welding can be guaranteed.

[0050] In specific manufacturing, the coupler of this embodiment can be fabricated from top to bottom using a low-temperature co-fired ceramic process. Specifically, the following can be stacked sequentially: the upper surface of the grounding shield layer 550, the substrate material, the first shield layer 410, the non-porous dielectric film, the first 1 / 8 wavelength planar coil 211, the porous dielectric film, the second 1 / 8 wavelength planar coil 212, the porous dielectric film, the third 1 / 8 wavelength planar coil 221, the porous dielectric film, the fourth 1 / 8 wavelength planar coil 222, the non-porous dielectric film, the fifth 1 / 8 wavelength planar coil 311, the porous dielectric film, the sixth 1 / 8 wavelength planar coil 312, the porous dielectric film, the seventh 1 / 8 wavelength planar coil 321, the porous dielectric film, the eighth 1 / 8 wavelength planar coil 322, the non-porous dielectric film, the second shield layer 420, the substrate material, and the lower surface of the grounding shield layer 550. The porous dielectric film has through holes for connecting the multilayer spiral inductor.

[0051] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0052] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0053] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A coupler, characterized in that, include: Matrix; A first stacked spiral inductor is disposed within the substrate. The first stacked spiral inductor includes a first spiral coil and a second spiral coil stacked together. The outer port of the first spiral coil is the first port of the coupler. The substrate is connected between the inner ports of the first and second spiral coils via a first through-hole. The outer port of the second spiral coil is the second port of the coupler. A second stacked spiral inductor is disposed within the substrate, and the second stacked spiral inductor is coupled to the first stacked spiral inductor. The second stacked spiral inductor includes a third spiral coil and a fourth spiral coil stacked together. The outer ring port of the third spiral coil is the third port of the coupler. The substrate is connected between the inner ring port of the third spiral coil and the inner ring port of the fourth spiral coil through a first through hole. The outer ring port of the fourth spiral coil is the fourth port of the coupler. The pattern of the second spiral coil is obtained by rotating the pattern of the first spiral coil by 180° along the height direction; the pattern of the third spiral coil is obtained by rotating the pattern of the second spiral coil by 180° along the length direction; the pattern of the fourth spiral coil is obtained by rotating the pattern of the third spiral coil by 180° along the height direction.

2. The coupler as described in claim 1, characterized in that, The first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil are stacked sequentially from top to bottom within the substrate.

3. The coupler as described in claim 1, characterized in that, The first port is disposed on the front surface of the substrate, and the length direction is parallel to the front surface.

4. The coupler as described in any one of claims 1 to 3, characterized in that, The first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil are all double-layer spiral coils, and each of the first spiral coil, the second spiral coil, the third spiral coil, and the fourth spiral coil consists of two parallel 1 / 8 wavelength planar coils.

5. The coupler as described in claim 4, characterized in that, The linewidth of the 1 / 8 wavelength planar coil is 100μm~130μm; the thickness of the 1 / 8 wavelength planar coil is 7μm~13μm.

6. The coupler as claimed in claim 4, characterized in that, The spacing between the first stacked spiral inductor and the second stacked spiral inductor is 0.65mm to 0.75mm; the spacing between the spiral coils in the same spiral inductor is 100μm to 135μm; and the spacing between the 1 / 8 wavelength planar coils in the same spiral coil is 5μm to 15μm.

7. The coupler as described in any one of claims 1 to 3, characterized in that, It also includes a first shielding layer and a second shielding layer disposed within the substrate. Both the first shielding layer and the second shielding layer are parallel to the first stacked spiral inductor and the second stacked spiral inductor. The first shielding layer is disposed above the first stacked spiral inductor, and the second shielding layer is disposed below the second stacked spiral inductor.

8. The coupler as claimed in any one of claims 1 to 3, characterized in that, The outer surface of the substrate is further provided with a first external electrode, a second external electrode, a third external electrode and a fourth external electrode. The first external electrode is connected to the first port, the second external electrode is connected to the second port, the third external electrode is connected to the third port, and the fourth external electrode is connected to the fourth port.

9. The coupler as claimed in any one of claims 1 to 3, characterized in that, The outer surface of the substrate is also provided with a grounding shield layer, which is used to connect to the ground terminal.

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