Radio frequency front-end module and electronic equipment

Abstract

The utility model discloses a radio frequency front-end module and electronic equipment. The radio frequency front-end module comprises a substrate, a power amplifier and a balun, the substrate is provided with a grounding metal layer, and the power amplifier comprises a first output end and a second output end. The balun comprises a capacitor, a primary coil and a secondary coil, the primary coil and the secondary coil are coupled, the primary coil and the secondary coil are wound on the substrate, and the primary coil is connected between the first output end and the second output end; one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the grounding metal layer through a plurality of metal via holes. When the capacitor is grounded, the technical scheme that the plurality of metal via holes are connected with the grounding metal layer is adopted, so that even if the radio frequency front-end module is applied to electronic equipment with a relatively poor grounding environment, the plurality of metal via holes can form a backflow path through good grounding of the metal via holes; the condition of harmonic deterioration caused by crosstalk of harmonic signals can be reduced or even avoided, and the transmission quality of radio frequency signals is improved.

Description

Technical Field

[0001] This application relates to the field of radio frequency technology, and more specifically, to a radio frequency front-end module and electronic device. Background Technology

[0002] Currently, radio frequency (RF) front-end modules are widely used in wireless communication, the Internet of Things (IoT), smart homes, and other fields. They can process RF signals (e.g., power amplification, filtering, etc.) to complete the tasks of receiving and transmitting RF signals.

[0003] In existing RF front-end modules, there is a problem of harmonic degradation, which in turn affects the normal transmission of RF signals. Utility Model Content

[0004] This application provides a radio frequency front-end module and an electronic device.

[0005] According to a first aspect of this application, an embodiment of this application provides a radio frequency (RF) front-end module, which includes a substrate, a power amplifier, and a balun. The substrate has a ground metal layer. The power amplifier is disposed on the substrate and includes a first output terminal and a second output terminal, which are used to output a pair of RF differential signals. The balun includes a capacitor, a coupled primary coil, and a secondary coil, which are respectively wound on the substrate. The primary coil is connected between the first and second output terminals. One end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the ground metal layer through multiple metal vias.

[0006] In some possible embodiments, multiple metal vias are arranged in an array at intervals on the substrate; the distance between two adjacent metal vias is greater than or equal to 110 μm and less than or equal to 140 μm.

[0007] In some possible embodiments, multiple metal vias are arranged in at least two rows in a specified direction; the metal vias in one row are staggered with the metal vias in the adjacent row.

[0008] In some possible embodiments, the diameter of the metal via is greater than or equal to 50 μm and less than or equal to 70 μm.

[0009] In some possible embodiments, the substrate has a designated area, and a plurality of metal vias are distributed within the designated area; the size of the designated area in a first direction is greater than or equal to 190 μm and less than or equal to 210 μm; the size of the designated area in a second direction is greater than or equal to 290 μm and less than or equal to 310 μm; the second direction is perpendicular to the first direction.

[0010] In some possible embodiments, the number of metal vias is positively correlated with the equivalent inductance of the primary coil.

[0011] In some possible embodiments, when the equivalent inductance of the primary coil is greater than or equal to 0.4nH and less than 0.5nH, the number of metal vias is greater than or equal to 4 and less than 6; when the equivalent inductance of the primary coil is greater than or equal to 0.5nH and less than or equal to 0.6nH, the number of metal vias is greater than or equal to 6 and less than or equal to 8.

[0012] In some possible embodiments, the substrate includes N metal layers stacked on top of each other, and the N metal layers include a ground metal layer; wherein N is less than or equal to 4, and the number of ground metal layers is less than or equal to 2.

[0013] In some possible embodiments, the operating frequency band of the radio frequency differential signal is the N77 band; the primary coil, capacitor and multiple metal vias are used to suppress a specified common-mode signal with a frequency greater than or equal to 6.6 GHz and less than or equal to 8.4 GHz.

[0014] According to a second aspect of this application, embodiments of this application also provide a radio frequency (RF) front-end module, which includes a substrate, a power amplifier, and a balun. The substrate includes N metal layers stacked on top of each other, including a ground metal layer; wherein N is less than or equal to 4. The power amplifier is disposed on the substrate; wherein the power amplifier includes a first output terminal and a second output terminal, the first and second output terminals being used to output a pair of RF differential signals. The balun includes a capacitor, a coupled primary coil, and a secondary coil, the primary and secondary coils being wound on the substrate respectively, the primary coil being connected between the first and second output terminals; one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the ground metal layer through multiple metal vias.

[0015] According to a third aspect of this application, embodiments of this application also provide an electronic device, which includes a motherboard and a radio frequency (RF) front-end module. The motherboard has a grounding region. The RF front-end module is disposed on the motherboard; the RF front-end module includes a substrate and a balun, the substrate having a grounding metal layer; the balun includes a capacitor and a primary coil, the primary coil being disposed on the substrate; one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the grounding metal layer through multiple metal vias; wherein the projections of the multiple metal vias in the thickness direction of the substrate do not coincide with the grounding region.

[0016] This application provides a radio frequency (RF) front-end module and electronic device. The RF front-end module includes a substrate, a power amplifier, and a balun. The substrate has a ground metal layer, and the power amplifier is disposed on the substrate and employs a differential architecture. The balun may include a capacitor, a coupled primary coil, and a secondary coil, which are wound on the substrate. The primary coil is connected to the power amplifier. Specifically, one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the ground metal layer through multiple metal vias.

[0017] Therefore, this application optimizes the connection between the midpoint of the primary coil and ground by using a combination of capacitors and multiple metal vias (i.e., grounding vias). The equivalent inductance and capacitance of the primary coil and the equivalent inductance of the multiple metal vias work together to suppress harmonic signals. For example, it can suppress the second common-mode harmonic signal to improve the harmonic degradation problem and ensure the normal transmission of radio frequency signals.

[0018] Furthermore, the capacitor in this application uses a technical solution of connecting multiple metal vias to the grounding metal layer when grounding. This allows multiple metal vias to form a return path through their own good grounding, even when the RF front-end module is used in electronic devices with poor grounding environment. Compared with the technical solution of grounding through a single metal via, this can reduce or even avoid the occurrence of harmonic signal crosstalk and thus harmonic degradation, thereby improving the transmission quality of RF signals. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the radio frequency front-end module provided in the embodiments of this application.

[0021] Figure 2 yes Figure 1 The diagram shows a cross-sectional view of the substrate in the RF front-end module.

[0022] Figure 3 yes Figure 1 The diagram shows a signal simulation of the RF front-end module.

[0023] Figure 4 yes Figure 1 A magnified view of region K in the diagram.

[0024] Figure 5 yes Figure 1The diagram shows the arrangement of multiple metal vias in the RF front-end module.

[0025] Figure 6 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0027] This application provides a radio frequency (RF) front-end module 100, which integrates two or more discrete components such as RF switches, low-noise amplifiers, filters, duplexers, and power amplifiers into a single independent module, thereby improving integration and hardware performance while miniaturizing the size. Specifically, the RF front-end module 100 is suitable for installation in electronic devices, where it is used to receive and transmit RF signals to realize the wireless communication function of the electronic device.

[0028] Please see Figure 1 and Figure 2 The RF front-end module 100 may include a substrate 20, a power amplifier 30, and a balun 40. The substrate 20 has a ground metal layer 2102. The power amplifier 30 is disposed on the substrate 20. The power amplifier 30 may include a first output terminal 302 and a second output terminal 304, which are used to output a pair of RF differential signals. The balun 40 may include a capacitor 410, a coupled primary coil 430, and a secondary coil 450, which are wound on the substrate 20. The primary coil 430 is connected between the first output terminal 302 and the second output terminal 304. Specifically, one end of the capacitor 410 is connected to the midpoint of the primary coil 430, and the other end of the capacitor 410 is connected to the ground metal layer 2102 through multiple metal vias 50.

[0029] Therefore, this embodiment optimizes the connection between the midpoint of the primary coil 430 and ground by using a combination of capacitor 410 and multiple metal vias 50 (i.e., grounding vias). The equivalent inductance of the primary coil 430, capacitor 410, and the equivalent inductance of the multiple metal vias 50 work together to suppress harmonic signals. For example, it can suppress the second common-mode harmonic signal to improve the harmonic degradation problem and ensure the normal transmission of radio frequency signals.

[0030] Furthermore, in this embodiment, when the capacitor 410 is grounded, a technical solution is adopted to connect the grounding metal layer 2102 with multiple metal vias 50. This means that even when the RF front-end module 100 is used in an electronic device with a poor grounding environment, the presence of multiple metal vias 50 can form a return path through their own good grounding. Compared with the technical solution of grounding through a single metal via 50, the crosstalk of harmonic signals can be reduced or even avoided, thus reducing the occurrence of harmonic degradation and improving the transmission quality of RF signals.

[0031] The specific implementation method of the radio frequency front-end module 100 is described below.

[0032] In this embodiment, the substrate 20 is generally rectangular and serves to fix and support the components (e.g., power amplifier 30, balun 40, etc.) in the RF front-end module 100. Specifically, the substrate 20 can be a copper-clad laminate. By performing hole processing, chemical copper plating, electroplating, etching, and other processes on the copper-clad laminate, circuits can be printed on the surface of the substrate 20.

[0033] In some possible embodiments, the substrate 20 may include N metal layers 210 stacked on top of each other, including the aforementioned ground metal layer 2102, which is used to ground components in the RF front-end module 100. N is less than or equal to 4 and greater than or equal to 2. For example, N can be equal to 2, 3, or 4. The number of ground metal layers 2102 is less than or equal to 2; for example, the number of ground metal layers 2102 can be 1 or 2. Exemplarily, in... Figure 2 In this case, N equals 4, and the number of grounding metal layers 2102 is 1. That is to say, the substrate 20 is provided with only one metal layer 210 for grounding. In this case, the grounding method may be imperfect, leading to harmonic degradation.

[0034] exist Figure 2 In the illustrated embodiment, the substrate 20 may include a substrate 250 and N-1 dielectric layers 230, wherein multiple metal layers 210 are sequentially stacked on the substrate 250. Specifically, the substrate 250 may be a silicon substrate, which serves to support the multiple metal layers 210. The metal layers 210 may be copper layers, which are used for laying out traces (e.g., equivalent traces of inductors, equivalent traces of primary coil 430 and secondary coil 450, etc.), or for setting a ground metal plate to form a ground metal layer 2102. In addition, the top metal layer 210 (i.e., the metal layer 210 with the largest distance from the substrate 250 among the N metal layers 210) may also be used to carry electronic components (e.g., chips, surface mount capacitors, etc.).

[0035] The dielectric layer 230 is disposed between two adjacent metal layers 210, serving as electrical isolation and insulation. Furthermore, the dielectric layer 230 may also have metal vias 50 to connect traces or electronic components located on different metal layers 210, for example... Figure 1 The capacitor 410 can be connected to the ground metal layer 2102 through the metal via 50. Specifically, the material of the dielectric layer 230 can be glass fiber, polytetrafluoroethylene, etc.

[0036] In this embodiment, the power amplifier 30 is disposed on the substrate 20 and is used to amplify the power of the input radio frequency signal. For example, the power amplifier 30 can be integrated into a chip, which can be connected to the substrate 20 using a flip-chip process or a bonding process. Specifically, the power amplifier 30 can be integrated into a heterojunction bipolar transistor (HBT) chip.

[0037] exist Figure 1 In the illustrated embodiment, the power amplifier 30 employs a differential architecture to convert the input radio frequency (RF) signal into a pair of RF differential signals for output. Specifically, the power amplifier 30 may include a first output terminal 302 and a second output terminal 304, which are used to output a pair of RF differential signals. In some possible embodiments, the first output terminal 302 and the second output terminal 304 may be located on the same side of the power amplifier 30 and symmetrically arranged about the central axis of the power amplifier 30 to ensure signal balance of the RF differential signals during output.

[0038] In this embodiment, the balun 40 serves to match impedance and combine a pair of radio frequency differential signals into a single radio frequency signal. The balun 40 may include a capacitor 410, a coupled primary coil 430, and a secondary coil 450, which are respectively wound on the substrate 20. For example, the primary coil 430 and the secondary coil 450 may be wound on different metal layers 210, and the projection of the primary coil 430 in the thickness direction of the substrate 20 coincides with at least a portion of the structure of the secondary coil 450 to achieve coupling between them. Specifically, the turns ratio between the primary coil 430 and the secondary coil 450 can be 4:1, 3:1, 2.5:1, 2:1, etc., and this embodiment does not impose a specific limitation.

[0039] In some possible embodiments, capacitor 410 can be a surface-mount device (SMD) mounted on the top metal layer 210 to make the overall structure of the RF front-end module 100 more compact. Similarly, primary coil 430 can be wound on the top metal layer 210 to be directly connected to capacitor 410 and improve the matching performance between primary coil 430 and capacitor 410. In addition, primary coil 430 is connected between the first output terminal 302 and the second output terminal 304 and can be symmetrically arranged about the central axis of power amplifier 30 to ensure signal balance of RF differential signal at input.

[0040] In this embodiment, one end of capacitor 410 is connected to the midpoint of primary coil 430, and the other end of capacitor 410 is connected to ground metal layer 2102 through multiple metal vias 50. Exemplarily, the operating frequency band of the radio frequency differential signal can be the N77 band. Of course, in some other possible embodiments, the operating frequency can also be the N78 band, N79 band, etc.

[0041] Specifically, the primary coil 430, capacitor 410, and multiple metal vias 50 can form an LC resonant structure to suppress a specified common-mode signal, such as a second common-mode harmonic signal. For example, when the operating frequency band of the RF differential signal is the N77 band, the frequency of the specified common-mode signal is greater than or equal to 6.6 GHz and less than or equal to 8.4 GHz.

[0042] It should be noted that in related technologies, when components (e.g., capacitor 410) disposed on substrate 20 are grounded, they are typically connected to the ground metal layer 2102 on substrate 20 by only one grounding via (i.e., metal via 50). In this case, if the grounding method of substrate 20 is not ideal (e.g., only one ground metal layer 2102 is provided), harmonic degradation will occur, thereby affecting the normal transmission of radio frequency signals.

[0043] To solve the above problems, this application proposes a technical solution where capacitor 410 is grounded by connecting multiple metal vias 50 to the grounding metal layer 2102. The presence of multiple metal vias 50 can form a return path through their own good grounding. Compared with the technical solution of grounding through a single metal via 50, it can reduce or even avoid the occurrence of harmonic signal crosstalk and thus the occurrence of harmonic degradation, thereby improving the transmission quality of radio frequency signals.

[0044] Please see Figure 3The diagram illustrates a signal simulation provided in this application. Curve 32 is the simulation curve corresponding to a single metal via 50 in related technologies, while curve 34 is the simulation curve corresponding to multiple metal vias 50 in this application. Figure 3 In this context, the frequency of the specified common-mode signal is greater than or equal to 6.6 GHz and less than or equal to 8.4 GHz.

[0045] It is easy to understand that when multiple metal vias 50 are provided, the multiple metal vias 50 can be regarded as being connected in parallel to ground, thereby reducing the equivalent inductance corresponding to the multiple metal vias 50, so as to increase the resonant frequency of the LC resonant structure formed by the primary coil 430, capacitor 410 and multiple metal vias 50.

[0046] Here we combine Figure 3 It is not difficult to observe that the position of the resonant point corresponding to curve 34 is significantly "shifted to the right" compared to the position of the resonant point corresponding to curve 32, allowing this resonant point to "fall" into the middle position of the frequency range corresponding to the specified common-mode signal, thereby effectively improving the suppression effect on the specified common-mode signal. Specifically in Figure 3 In the diagram, the resonant point corresponding to curve 32 is located at 6.8 GHz, while the resonant point corresponding to curve 34 is located at 7.5 GHz, which is roughly in the middle of the frequency range [6.6 GHz, 8.4 GHz], thus achieving a good broadband suppression effect for the specified common-mode signal.

[0047] The following describes how to set up multiple metal vias 50.

[0048] Please see Figure 4 The substrate 20 may have a designated region K, within which multiple metal vias 50 are distributed. Specifically, the dimension of the designated region K in the first direction X is greater than or equal to 190 μm and less than or equal to 210 μm; for example, the dimension in the first direction X can be 190 μm, 200 μm, 210 μm, etc. The dimension of the designated region K in the second direction Y is greater than or equal to 290 μm and less than or equal to 310 μm; for example, the dimension in the second direction Y can be 290 μm, 300 μm, 310 μm, etc. The second direction Y is perpendicular to the first direction X. Figure 1 and Figure 4 In the illustrated embodiment, the first direction X is the length direction of the substrate 20, and the second direction Y is the width direction of the substrate 20. In some other possible embodiments, the first direction X may be the width direction of the substrate 20, and the second direction Y may be the length direction of the substrate 20; this embodiment does not limit this.

[0049] Specifically, the designated area K can be at least a portion of the outer region of the plurality of metal vias 50. For example, the designated area K can be a rectangular area of ​​200μm*300μm. Therefore, in this embodiment, the plurality of metal vias 50 are set in the designated area K, which has a relatively small area, thus saving layout space on the substrate 20.

[0050] In some possible embodiments, a plurality of metal vias 50 are arranged in an array at intervals on the substrate 20. The number of metal vias 50 can be greater than or equal to 4 and less than or equal to 8. For example, the number of metal vias 50 can be 4, 5, 6, 7, 8, etc. Figure 4 In this configuration, the number of metal vias of size 50 is equal to 5. See also... Figure 5 , Figure 5 Regions (a), (b), (c), and (d) show schematic diagrams of the arrangement of metal vias 50 with the numbers 4, 6, 7, and 8, respectively.

[0051] In some possible embodiments, a plurality of metal vias 50 are arranged in at least two rows in a specified direction, wherein the metal vias 50 in one row are staggered with the metal vias 50 in the adjacent row. Specifically, in the vertical direction of the specified direction, the metal vias 50 in one row are directly opposite the gap formed by the metal vias 50 in the adjacent row (e.g., Figure 5 As shown in regions (c) and (d) in the diagram, the two rows of metal vias 50 are arranged with a certain positional offset, so that the multiple metal vias 50 are arranged in an array and staggered, reducing the overall space occupied by the multiple metal vias 50, thereby saving the layout space of the substrate 20.

[0052] Of course, in some other possible embodiments, in the vertical direction of the specified direction, the metal vias 50 in one row are directly opposite to the metal vias 50 in the adjacent row. In this case, the multiple metal vias 50 are arranged in an M*N array (e.g., Figure 5 (As shown in regions (a) and (b)). Specifically, this embodiment does not specifically limit the arrangement of the multiple metal vias 50.

[0053] Please refer to it again. Figure 4 The spacing L between two adjacent metal vias 50 is greater than or equal to 110 μm and less than or equal to 140 μm. For example, the spacing L can be 110 μm, 120 μm, 125 μm, 130 μm, 140 μm, etc. The diameter of the metal via 50 is greater than or equal to 50 μm and less than or equal to 70 μm. For example, the diameter can be 50 μm, 60 μm, 70 μm, etc. Therefore, in this embodiment, there is a certain spacing between two adjacent metal vias 50, which can avoid mutual coupling between two adjacent metal vias 50, further reduce parasitic effects, and improve the suppression capability of specified common-mode signals.

[0054] It should be noted that the total inductance of the LC resonant structure formed by the primary coil 430, capacitor 410, and multiple metal vias 50 needs to be within a fixed range. Therefore, the larger the equivalent inductance of the primary coil 430, the smaller the equivalent inductance of the multiple metal vias 50. Since the multiple metal vias 50 are connected to ground in parallel, the smaller the equivalent inductance of the multiple metal vias 50, the larger the number of metal vias 50. In other words, in this embodiment, the number of metal vias 50 and the equivalent inductance of the primary coil 430 are positively correlated to ensure successful suppression of the specified common-mode signal.

[0055] Specifically, when the equivalent inductance of the primary coil 430 is greater than or equal to 0.4nH and less than 0.5nH, the number of metal vias 50 is greater than or equal to 4 and less than 6. When the equivalent inductance of the primary coil 430 is greater than or equal to 0.5nH and less than or equal to 0.6nH, the number of metal vias 50 is greater than or equal to 6 and less than or equal to 8. For example, when the equivalent inductance of the primary coil 430 is 0.4nH, the number of metal vias 50 is 4; when the equivalent inductance of the primary coil 430 is 0.5nH, the number of metal vias 50 is 6; and when the equivalent inductance of the primary coil 430 is 0.6nH, the number of metal vias 50 is 8.

[0056] This application provides a radio frequency (RF) front-end module 100, which may include a substrate 20, a power amplifier 30, and a balun 40. The substrate 20 has a ground metal layer 2102. The power amplifier 30 is disposed on the substrate 20. The power amplifier 30 may include a first output terminal 302 and a second output terminal 304, which are used to output a pair of RF differential signals. The balun 40 may include a capacitor 410, a coupled primary coil 430, and a secondary coil 450, which are wound on the substrate 20. The primary coil 430 is connected between the first output terminal 302 and the second output terminal 304. Specifically, one end of the capacitor 410 is connected to the midpoint of the primary coil 430, and the other end of the capacitor 410 is connected to the ground metal layer 2102 through multiple metal vias 50.

[0057] Therefore, this embodiment optimizes the connection between the midpoint of the primary coil 430 and ground by using a combination of capacitor 410 and multiple metal vias 50 (i.e., grounding vias). The equivalent inductance of the primary coil 430, capacitor 410, and the equivalent inductance of the multiple metal vias 50 work together to suppress harmonic signals. For example, it can suppress the second common-mode harmonic signal to improve the harmonic degradation problem and ensure the normal transmission of radio frequency signals.

[0058] Furthermore, in this embodiment, when the capacitor 410 is grounded, a technical solution is adopted to connect the grounding metal layer 2102 with multiple metal vias 50. This means that even when the RF front-end module 100 is used in an electronic device with a poor grounding environment, the presence of multiple metal vias 50 can form a return path through their own good grounding. Compared with the technical solution of grounding through a single metal via 50, the crosstalk of harmonic signals can be reduced or even avoided, thus reducing the occurrence of harmonic degradation and improving the transmission quality of RF signals.

[0059] This application embodiment also provides a radio frequency (RF) front-end module 100, which may include a substrate 20, a power amplifier 30, and a balun 40. The substrate 20 may include N stacked metal layers 210, including a ground metal layer 2102; wherein N is less than or equal to 4. The power amplifier 30 is disposed on the substrate 20; wherein the power amplifier 30 includes a first output terminal 302 and a second output terminal 304, which are used to output a pair of RF differential signals. The balun 40 may include a capacitor 410, a coupled primary coil 430, and a secondary coil 450, which are wound on the substrate 20 respectively. The primary coil 430 is connected between the first output terminal 302 and the second output terminal 304. One end of the capacitor 410 is connected to the midpoint of the primary coil 430, and the other end of the capacitor 410 is connected to the ground metal layer 2102 through multiple metal vias 50.

[0060] Specifically, for details regarding the substrate 20, power amplifier 30, and balun 40, as well as their specific implementation methods, please refer to the detailed descriptions in the embodiments above, which will not be repeated here.

[0061] Therefore, this embodiment optimizes the connection between the midpoint of the primary coil 430 and ground by using a combination of capacitor 410 and multiple metal vias 50 (i.e., grounding vias). The equivalent inductance of the primary coil 430, capacitor 410, and the equivalent inductance of the multiple metal vias 50 work together to suppress harmonic signals. For example, it can suppress the second common-mode harmonic signal to improve the harmonic degradation problem and ensure the normal transmission of radio frequency signals.

[0062] Furthermore, in this embodiment, when the capacitor 410 is grounded, a technical solution is adopted to connect the grounding metal layer 2102 with multiple metal vias 50. This means that even when the RF front-end module 100 is used in an electronic device with a poor grounding environment, the presence of multiple metal vias 50 can form a return path through their own good grounding. Compared with the technical solution of grounding through a single metal via 50, the crosstalk of harmonic signals can be reduced or even avoided, thus reducing the occurrence of harmonic degradation and improving the transmission quality of RF signals.

[0063] This embodiment also provides an electronic device 600, which can be a 4G or 5G communication device such as a smartphone, tablet, or smartwatch. Specifically, the electronic device 600 may include the radio frequency front-end module 100 in the above embodiment to realize the reception and transmission of radio frequency signals. Furthermore, with the development of 5G technology, the performance requirements for radio frequency front-end modules are becoming increasingly stringent. The technical solution of this application can be applied to 5G radio frequency front-end modules to improve the communication performance of 5G communication devices.

[0064] Please see Figure 6 The electronic device 600 may include a motherboard 70 and an RF front-end module 100. The motherboard 70 integrates multiple hardware components within the fixed electronic device 600. Specifically, the motherboard 70 may integrate a processor (CPU), a graphics processing unit (GPU), RAM, ROM / Flash Memory, and the RF front-end module 100, etc. Furthermore, the motherboard 70 also has a grounding area 720, which provides a unified zero-potential reference point for the multiple hardware components in the electronic device 600 to ensure stable signal transmission. In addition, the grounding area 720 can reduce electromagnetic interference to avoid signal crosstalk and distortion.

[0065] It should be noted that when electronic device 600 is in the testing and development phase, motherboard 70 can be understood as the EVB test board used in the testing and development phase.

[0066] The radio frequency front-end module 100 is disposed on the motherboard 70, and may include a substrate 20 and a balun 40. The substrate 20 has a ground metal layer 2102, and the balun 40 may include a capacitor 410 and a primary coil 430, with the primary coil 430 disposed on the substrate 20. One end of the capacitor 410 is connected to the midpoint of the primary coil 430, and the other end of the capacitor 410 is connected to the ground metal layer 2102 through multiple metal vias 50. For a detailed description of the radio frequency front-end module 100 and its specific implementation, please refer to the detailed description in the above embodiments; further elaboration will not be repeated here.

[0067] In this embodiment, the projections of the multiple metal vias 50 onto the thickness direction of the substrate 20 do not coincide with the grounding region 720. That is, the electronic device 600 in this embodiment cannot provide a good grounding environment for the RF front-end module 100. In this situation, the presence of multiple metal vias 50 can form a return path through their own good grounding. Compared to the technical solution of grounding through a single metal via 50, this can reduce or even avoid harmonic signal crosstalk and subsequent harmonic degradation, thus improving the transmission quality of the RF signal.

[0068] In this application specification, certain terms are used to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. The specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" throughout the specification and claims is an open-ended term and should be interpreted as "including but not limited to"; "generally" means that those skilled in the art can solve the technical problem within a certain margin of error and basically achieve the technical effect.

[0069] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "inside", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the purpose of simplifying the description of this application 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.

[0070] In this application, unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or merely surface contact. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0071] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0072] 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 at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0073] Finally, it should be noted that the above 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.

Claims

1. A radio frequency front-end module, characterized in that, The application relates to a power amplifier, which comprises a substrate provided with a ground metal layer; a power amplifier arranged on the substrate, wherein the power amplifier comprises a first output end and a second output end for outputting a pair of radio frequency differential signals; and a balun comprising a capacitor, a primary coil and a secondary coil which are coupled to each other, wherein the primary coil and the secondary coil are arranged on the substrate respectively, the primary coil is connected between the first output end and the second output end, one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the ground metal layer through a plurality of metal vias. The plurality of metal vias are arranged in an array on the substrate. The distance between two adjacent metal vias is greater than or equal to 110 mu m and less than or equal to 140 mu m. The plurality of metal vias are arranged in at least two rows in a specified direction, and the metal vias in one row are staggered with the metal vias in the adjacent row.

2. The radio frequency front-end module of claim 1, wherein, The diameter of the metal via is greater than or equal to 50 mu m and less than or equal to 70 mu m. The substrate is provided with a specified area, and the plurality of metal vias are distributed in the specified area.

3. The radio frequency front-end module of claim 2, wherein, The size of the specified area in the first direction is greater than or equal to 190 mu m and less than or equal to 210 mu m, and the size of the specified area in the second direction is greater than or equal to 290 mu m and less than or equal to 310 mu m.

4. The radio frequency front-end module of claim 1, wherein, The number of the metal vias and the equivalent inductance value of the primary coil are in a positive correlation.

5. The radio frequency front end module of claim 1, wherein, When the equivalent inductance value of the primary coil is greater than or equal to 0.4 nH and less than 0.5 nH, the number of the metal vias is greater than or equal to 4 and less than 6. When the equivalent inductance value of the primary coil is greater than or equal to 0.5 nH and less than or equal to 0.6 nH, the number of the metal vias is greater than or equal to 6 and less than or equal to 8.

6. The radio frequency front-end module of any one of claims 1 to 5, wherein, The substrate comprises N metal layers which are stacked with each other, and the N metal layers comprise the ground metal layer; wherein N is less than or equal to 4, and the number of the ground metal layers is less than or equal to 2.

7. The radio frequency front-end module of claim 6, wherein, The working frequency band of the radio frequency differential signal is N77 frequency band. The primary coil, the capacitor and the plurality of metal vias are used for suppressing a specified common mode signal, and the frequency of the specified common mode signal is greater than or equal to 6.6 GHz and less than or equal to 8.4 GHz.

8. The radio frequency front-end module of any one of claims 1 to 5, wherein, The application relates to a power amplifier, which comprises a substrate provided with a ground metal layer; a power amplifier arranged on the substrate, wherein the power amplifier comprises a first output end and a second output end for outputting a pair of radio frequency differential signals; and a balun comprising a capacitor, a primary coil and a secondary coil which are coupled to each other, wherein the primary coil and the secondary coil are arranged on the substrate respectively, the primary coil is connected between the first output end and the second output end, one end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the ground metal layer through a plurality of metal vias.

9. The radio frequency front-end module of any one of claims 1 to 5, wherein, ​ ​ 10. A radio frequency front end module, comprising: ​ ​ ​ ​ 11. An electronic device, comprising: The application relates to a radio frequency front end module. The radio frequency front end module comprises a substrate and a balun. The substrate is provided with a grounding area. The balun comprises a capacitor and a primary coil. One end of the capacitor is connected to the midpoint of the primary coil, and the other end of the capacitor is connected to the grounding area through a plurality of metal vias. The projections of the plurality of metal vias in the thickness direction of the substrate do not coincide with the grounding area.

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