An impedance conversion circuit, a radio frequency front end module and an electronic device

Abstract

The application relates to the technical field of radio frequency circuits, and discloses an impedance conversion circuit, a radio frequency front end module and electronic equipment, the impedance conversion circuit comprising: a single-end transformer, a first resonant circuit, a second resonant circuit and a low-frequency suppression circuit, wherein one end of the primary coil is connected with the first end of the low-frequency suppression circuit, the second end of the low-frequency suppression circuit is connected with the first end of the first resonant circuit and the first port respectively, and the first end of the second resonant circuit is connected with one end of the secondary coil and the second port respectively. The circuit modules are coordinated and work together, and in a target working frequency band, the radio frequency system can be precisely and low-loss converted from 50 omega standard impedance to 3-5 omega low impedance, and the technical pain points of a traditional passive LC matching network, such as narrow bandwidth, low transmission efficiency and the need to design a complex adjustable matching structure, are solved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency circuit technology, specifically to an impedance transformation circuit, a radio frequency front-end module, and an electronic device. Background Technology

[0002] In radio frequency (RF) front-end circuits, the matching network is a core component for achieving efficient signal transmission. Essentially, it transforms the 50Ω standard system impedance to the amplifier's optimal operating impedance, ensuring reflection-free and low-loss signal transmission. Currently, most RF front-end matching networks use passive LC networks for impedance transformation. However, passive LC networks have inherent frequency selectivity, and their impedance transformation capability is only effective within a limited narrow bandwidth, making it difficult to cover the wideband requirements of RF applications such as 5G and Wi-Fi 6E.

[0003] To address wideband matching issues, traditional technologies either sacrifice circuit transmission efficiency or require complex adjustable matching structures. This not only increases the size, cost, and design complexity of RF modules but also makes it difficult to meet the high integration and miniaturization requirements of SiP (System-in-Package). Furthermore, traditional narrowband LC matching networks have weak clutter suppression capabilities, failing to effectively filter both high-order harmonics and low-frequency clutter simultaneously, which can lead to signal quality degradation and negatively impact the overall performance of the RF module. Summary of the Invention

[0004] This invention provides an impedance transformation circuit, a radio frequency front-end module, and an electronic device to solve the problems of narrow bandwidth, low efficiency, weak noise suppression capability, and difficulty in adapting to the miniaturization requirements of SiP packaging in traditional passive LC matching networks.

[0005] In a first aspect, the present invention provides an impedance transformation circuit, the circuit comprising: a single-ended transformer, a first resonant circuit, a second resonant circuit, and a low-frequency suppression circuit, wherein,

[0006] One end of the primary coil of the single-ended transformer serves as the signal input terminal, and the other end of the primary coil of the single-ended transformer is grounded. One end of the secondary coil of the single-ended transformer serves as the load output terminal, and the other end of the secondary coil of the single-ended transformer is grounded. The first terminal of the low-frequency suppression circuit is connected to one end of the primary coil, the second terminal of the low-frequency suppression circuit is connected to the first terminal and the first port of the first resonant circuit respectively, the third terminal of the low-frequency suppression circuit is grounded, and the second terminal of the first resonant circuit is grounded. The first end of the second resonant circuit is connected to one end of the secondary coil and the second port, respectively, and the second end of the second resonant circuit is grounded.

[0007] This invention provides an impedance transformation circuit that uses a single-ended transformer as its core to achieve broadband impedance transformation of radio frequency signals. Through a first resonant circuit and a second resonant circuit located on the primary and secondary sides of the transformer, precise suppression of high-order harmonics on both sides is achieved. Simultaneously, a low-frequency suppression circuit effectively filters out low-frequency noise across a wide frequency band. The various circuit modules work collaboratively to achieve precise, low-loss conversion of the 50Ω standard impedance of the radio frequency system to a low impedance of 3~5Ω within the target operating frequency band of 2.3G-2.7G. This effectively solves the technical pain points of traditional passive LC matching networks, such as narrow bandwidth, low transmission efficiency, and the need for complex adjustable matching structures. It also perfectly adapts to the miniaturization and high integration requirements of SiP packaging, achieving multiple technical effects such as precise impedance transformation, full-band noise filtering, and efficient radio frequency power transmission.

[0008] In one optional embodiment, the low-frequency suppression circuit includes: a first capacitor and a first inductor, wherein, One end of the first capacitor is connected to one end of the primary coil, and the other end of the first capacitor is connected to one end of the first inductor and the first end of the first resonant circuit, respectively. The other end of the first inductor is grounded.

[0009] In one alternative embodiment, the first resonant circuit includes: a second capacitor and a second inductor, wherein, One end of the second capacitor is connected to the other end of the first capacitor, one end of the first inductor, and the first port, respectively. The other end of the second capacitor is connected to one end of the second inductor, and the other end of the second inductor is grounded.

[0010] In one alternative embodiment, the second resonant circuit includes: a third capacitor and a third inductor, wherein, One end of the third capacitor is connected to one end of the secondary coil and the second port, respectively. The other end of the third capacitor is connected to one end of the third inductor, and the other end of the third inductor is grounded.

[0011] In one alternative implementation, the single-ended transformer employs an upper and lower coil structure.

[0012] In one alternative implementation, the first capacitor is further used in conjunction with the single-ended transformer to achieve LC frequency selection.

[0013] In one alternative implementation, the third capacitor is also used in conjunction with the single-ended transformer to participate in target frequency impedance matching.

[0014] In a second aspect, the present invention provides a radio frequency front-end module, including: the impedance transformation circuit of the first aspect above or any corresponding embodiment thereof.

[0015] This invention provides a radio frequency (RF) front-end module that integrates a single-ended transformer-type impedance transformation circuit. It is a miniaturized, highly integrated RF front-end module that is compatible with GaAs / GaN power amplifiers and designed for the 2.3G-2.7G RF operating frequency band. Relying on the broadband impedance conversion and full-band clutter suppression characteristics of the impedance transformation circuit, it solves the technical problems of narrow bandwidth, low efficiency, and difficulty in miniaturization of traditional passive LC matching networks. It can be directly applied to RF communication equipment such as 5G FR1 small base stations, Wi-Fi 6E (2.4GHz extension), and IoT private networks.

[0016] Thirdly, the present invention provides an electronic device comprising: a radio frequency front-end module according to the second aspect above or any corresponding embodiment thereof.

[0017] This invention provides an electronic device equipped with the aforementioned radio frequency front-end module. It is a communication electronic device designed for mid-to-high frequency communication scenarios such as 5G, Wi-Fi 6E, and IoT private networks. Relying on the core characteristics of the radio frequency front-end module, such as wideband impedance matching, low-loss transmission, and full-band noise suppression, it achieves efficient processing and transmission of the device's radio frequency signals. This solves the problems of insufficient bandwidth, low transmission efficiency, and large module size caused by narrowband matching networks in traditional device radio frequency front-ends. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a block diagram of the impedance transformation circuit according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the impedance transformation circuit according to an embodiment of the present invention; Figure 3 This is a schematic diagram of simulation results according to an embodiment of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0022] 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 invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] This invention provides an impedance transformation circuit, such as Figure 1 As shown, the circuit includes: a single-ended transformer, a first resonant circuit, a second resonant circuit, and a low-frequency suppression circuit. One end of the primary coil of the single-ended transformer serves as the signal input terminal, and the other end is grounded. One end of the secondary coil serves as the load output terminal, and the other end is grounded. The first terminal of the low-frequency suppression circuit is connected to one end of the primary coil. The second terminal of the low-frequency suppression circuit is connected to both the first terminal and the first port of the first resonant circuit. The third terminal of the low-frequency suppression circuit is grounded, and the second terminal of the first resonant circuit is grounded. The first terminal of the second resonant circuit is connected to both one end of the secondary coil and the second port, and the second terminal of the second resonant circuit is grounded.

[0024] Specifically, the 50Ω standard signal of the RF system is input to the circuit from the signal input terminal of the primary coil of the single-ended transformer. The other end of the primary coil is directly grounded. One end of the secondary coil serves as the output terminal for a 3~5Ω low-impedance load, connecting to the subsequent amplifier devices. The other end is also grounded, forming the standard single-ended operating mode of the single-ended transformer. This single-ended transformer achieves efficient energy transfer from the primary coil to the secondary coil through the principle of electromagnetic coupling, laying the foundation for the transformation of the 50Ω system impedance to a 3~5Ω low impedance. At the same time, the transformer's structural design ensures in-band flatness within the 2.3G-2.7G operating frequency band, meeting the requirements of wideband signal transmission.

[0025] Before the main radio frequency signal enters the primary coil, it is processed by a low-frequency suppression circuit. This low-frequency suppression circuit utilizes the frequency characteristics of inductors and capacitors to present high impedance to low-frequency noise below 2.3 GHz, effectively blocking low-frequency noise in the main signal link and preventing it from entering the transformer and participating in electromagnetic coupling. At the same time, the blocked low-frequency noise is quickly discharged to ground through the direct grounding path of the third terminal and the first port connected to the second terminal, ensuring the purity of the main signal frequency band entering the single-ended transformer.

[0026] While low-frequency noise is filtered out, the first and second resonant circuits precisely suppress high-order harmonics generated on the primary and secondary sides of the transformer, respectively. The first resonant circuit exhibits low impedance characteristics for high-order harmonics generated by electromagnetic coupling on the primary coil side, quickly dissipating them through the ground terminal. Simultaneously, the first port provides a clean RF ground reference, reducing interference from ground parasitic parameters on the harmonic suppression effect. The second resonant circuit is designed with matched resonant parameters to address high-order harmonics generated during secondary coil coupling, dissipating them through the ground terminal to prevent them from entering the subsequent GaAs / GaN PA and affecting amplification efficiency. The second port also prevents electromagnetic coupling interference between the circuit and the primary-side grounding loop, adapting to the grounding design requirements of high-integration SiP packages.

[0027] This invention provides an impedance transformation circuit that uses a single-ended transformer as its core to achieve broadband impedance transformation of radio frequency signals. Through a first resonant circuit and a second resonant circuit located on the primary and secondary sides of the transformer, precise suppression of high-order harmonics on both sides is achieved. Simultaneously, a low-frequency suppression circuit effectively filters out low-frequency noise across a wide frequency band. The various circuit modules work collaboratively to achieve precise, low-loss conversion of the 50Ω standard impedance of the radio frequency system to a low impedance of 3~5Ω within the target operating frequency band of 2.3G-2.7G. This effectively solves the technical pain points of traditional passive LC matching networks, such as narrow bandwidth, low transmission efficiency, and the need for complex adjustable matching structures. It also perfectly adapts to the miniaturization and high integration requirements of SiP packaging, achieving multiple technical effects such as precise impedance transformation, full-band noise filtering, and efficient radio frequency power transmission.

[0028] In one alternative implementation, both the first port and the second port are electrical ports configured with independent grounding.

[0029] Specifically, this independent grounding design provides a stable and clean grounding reference for the low-frequency suppression circuit, the first resonant circuit, and the second resonant circuit, avoiding parasitic parameter interference, signal crosstalk, and resonant frequency shift caused by sharing a grounding loop between different functional circuits. This improves the working stability, harmonic suppression accuracy, and impedance matching consistency of the impedance transformation circuit in a highly integrated package environment, ensuring low-loss and high-efficiency transmission of RF signals over a wide bandwidth.

[0030] In one alternative implementation, such as Figure 2 As shown, the low-frequency suppression circuit includes a first capacitor C1 and a first inductor L1. One end of the first capacitor C1 is connected to one end of the primary coil, and the other end of the first capacitor C1 is connected to one end of the first inductor L1 and the first end of the first resonant circuit. The other end of the first inductor L1 is grounded.

[0031] Specifically, the low-frequency suppression circuit is a high-pass filter structure composed of the first capacitor C1 and the first inductor L1, which serves as the first filtering barrier before the RF main signal enters the single-ended transformer TF1. The first capacitor C1 exhibits low capacitive reactance for RF main signals in the 2.3G-2.7G range, allowing the main signal to pass through without loss, while exhibiting high capacitive reactance for low-frequency noise below 2.3G, forming an initial blockage. The first inductor L1 exhibits high inductive reactance for low-frequency noise, further blocking low-frequency noise from entering the single-ended transformer TF1, and exhibits low inductive reactance for the RF main signal, without affecting the main signal transmission.

[0032] Low-frequency noise blocked by the first capacitor C1 and the first inductor L1 is quickly discharged to ground through the direct grounding path of the first inductor L1 and the auxiliary grounding path formed by the first port, preventing low-frequency noise from entering the single-ended transformer TF1 to participate in electromagnetic coupling, allowing only the target main frequency band signal of 2.3G-2.7G to pass through, ensuring the purity of the signal entering the transformer.

[0033] In this embodiment, the first capacitor C1 is a series capacitor integrated inside the chip, which is also used to cooperate with the single-ended transformer TF1 to achieve LC frequency selection. The first capacitor C1 and the coil of the single-ended transformer form an LC frequency selection circuit. Through device parameter matching, the main frequency signal of 2.3G-2.7G is further accurately screened, the selection effect of the main frequency band is enhanced, the frequency selectivity of the circuit is improved, and the circuit can identify and transmit signals in the target operating frequency band more effectively.

[0034] In one alternative implementation, such as Figure 2 As shown, the first resonant circuit includes: a second capacitor C2 and a second inductor L2, wherein one end of the second capacitor C2 is connected to the other end of the first capacitor C1, one end of the first inductor L1 and the first port TermG1 respectively, the other end of the second capacitor C2 is connected to one end of the second inductor L2, and the other end of the second inductor L2 is grounded.

[0035] Specifically, the first resonant circuit is an LC resonant structure composed of a second capacitor and a second inductor connected in series. It utilizes the frequency gating characteristics of LC series resonance to achieve precise suppression of high-order harmonics on the primary side. During electromagnetic coupling, the primary coil of the single-ended transformer TF1 generates high-order harmonics. Simultaneously, a small amount of unfiltered high-frequency noise remains in the RF main signal link. When this noise passes through the first resonant circuit, because the circuit exhibits low impedance at the harmonic frequencies, it is directly discharged to ground through the grounding path of the second inductor L2, preventing it from entering the transformer and participating in impedance transformation. This avoids interference from high-order harmonics on the transformer's impedance transformation accuracy and in-band flatness at the source. At the same time, the first port TermG1 provides a clean RF ground reference for the first resonant circuit, preventing ground parasitic parameters from causing resonant frequency shifts and ensuring the stability of harmonic suppression.

[0036] In one alternative implementation, such as Figure 2 As shown, the second resonant circuit includes a third capacitor C3 and a third inductor L3. One end of the third capacitor C3 is connected to one end of the secondary coil and the second port TermG2, respectively. The other end of the third capacitor C3 is connected to one end of the third inductor L3, and the other end of the third inductor L3 is grounded.

[0037] Specifically, the second resonant circuit is an LC resonant structure composed of a third capacitor C3 and a third inductor L3 connected in series. It is connected between the load output terminal of the secondary coil of the single-ended transformer TF1 and ground. It is the core of secondary-side noise suppression and also has the auxiliary function of impedance matching at the main frequency. By matching the parameters of the third capacitor C3 and the third inductor L3, the resonant frequency of the first resonant circuit is matched with the high-order harmonic frequency of the secondary side. It presents low impedance at the harmonic frequency, and the high-order harmonics generated by the secondary coil of the single-ended transformer TF1 during electromagnetic coupling are discharged to ground through the grounding path of the third inductor L3. This prevents the high-order harmonics from entering the subsequent HBT chip, prevents harmonic interference with the normal operation of the amplifier, and improves amplification efficiency.

[0038] In this embodiment, the third capacitor is a substrate capacitor, which is mounted on the output terminal of the secondary coil of the single-ended transformer TF1. It also works with the single-ended transformer TF1 to participate in the target main frequency impedance matching. The target main frequency impedance is 3~5Ω. The third capacitor, in conjunction with the inductance characteristics of the secondary coil, can fine-tune the overall impedance characteristics of the secondary side, allowing for a more precise match between the 3~5Ω low impedance converted by the single-ended transformer TF1 and the input impedance of the subsequent HBT chip, further reducing signal reflection and improving power transmission efficiency. At the same time, the second port TermG2 provides an independent ground for the second resonant circuit, avoiding electromagnetic coupling interference with the primary side grounding loop, and adapting to the grounding design requirements of the high integration of SiP packaging.

[0039] In one alternative implementation, the single-ended transformer TF1 employs an upper and lower coil structure.

[0040] Specifically, the clean RF main signal, after being filtered by the low-frequency suppression circuit and the first resonant circuit to remove low-frequency noise and primary-side high-order harmonics, enters the primary coil of the single-ended transformer TF1 and generates an alternating magnetic field. This magnetic field is then transferred to the secondary coil via electromagnetic coupling. Utilizing the square relationship between the turns ratio and impedance transformation ratio of the single-ended transformer TF1 (a turns ratio of 1:3 corresponds to an impedance transformation ratio of 1:9), the 50Ω standard high impedance of the RF system is precisely converted to a 3~5Ω low impedance suitable for GaAs / GaN PAs, meeting the optimal operating impedance requirements of the power amplifier. Compared to traditional passive LC matching networks, the electromagnetic coupling method of the single-ended transformer TF1 has no obvious frequency selectivity, ensuring in-band flatness across the entire 2.3G-2.7G operating frequency band while providing sufficient bandwidth. This solves the technical problems of insufficient bandwidth and reduced efficiency in traditional narrowband matching networks. Furthermore, the real-part convergence characteristic of the single-ended transformer TF1 ensures efficient transmission of RF power between the primary and secondary coils, laying the foundation for subsequent signal amplification. In this embodiment, the single-ended transformer TF1 adopts a compact structure design and can be directly integrated into a miniaturized radio frequency module.

[0041] Furthermore, while keeping the core topology of the impedance transformation circuit unchanged, the impedance transformation structure can be adapted to other RF operating frequency bands other than 2.3G-2.7G by adjusting the parameter specifications of each component in the circuit.

[0042] In one optional implementation, the overall simulation verification of this solution is completed based on a SiP packaging scenario, adapting to the 2.3G-2.7G RF operating frequency band; wherein the structural dimension of the single-ended transformer is approximately 0.8mm. The thickness is 0.65mm, and it is designed and manufactured using a four-layer PCB board. Furthermore, this solution has completed the entire process of 3D modeling and electromagnetic (EM) simulation using HFSS software, which fully verifies the feasibility of the structural design and circuit operation.

[0043] See Figure 3 Simulation results show that the impedance transformation circuit possesses excellent electrical characteristics with real-part convergence, effectively ensuring efficient transmission of RF power during transmission and impedance transformation. The circuit exhibits excellent loss performance with an in-band transmission loss of only 0.8dB in the 2.3GHz-2.7GHz operating frequency band, and its reflection coefficient S11 is less than -10dB across the entire frequency band, demonstrating good impedance matching. Furthermore, the circuit effectively suppresses low-frequency noise and high- and low-end harmonics through the aforementioned LC network, resulting in excellent noise filtering capability across the entire frequency band. In addition, the single-ended transformer has a coil turns ratio of approximately 1:3, corresponding to an impedance transformation ratio of 1:9, which can accurately convert the standard 50Ω high impedance of the RF system to a 3~5Ω low impedance suitable for GaAs / GaN PAs, meeting the optimal operating impedance requirements of the power amplifier.

[0044] This invention provides a radio frequency front-end module, comprising: Figures 1-2 The impedance transformation circuit shown.

[0045] Specifically, Figure 1 and Figure 2 The impedance transformation circuit shown is suitable not only for SiP system-in-package (SiP) solutions but also for single-chip solutions. This RF front-end module integrates... Figure 1 and Figure 2 The single-ended transformer impedance transformation circuit shown is a miniaturized, highly integrated RF front-end module adapted to GaAs / GaN power amplifiers and designed for the 2.3G-2.7G RF operating frequency band. Relying on the broadband impedance transformation and full-band clutter suppression characteristics of the impedance transformation circuit, it solves the technical problems of narrow bandwidth, low efficiency, and difficulty in miniaturization of traditional passive LC matching networks. It can be directly applied to RF communication equipment such as 5G FR1 small base stations, Wi-Fi 6E (2.4GHz extension), and IoT private networks.

[0046] The present invention provides an electronic device, including: the radio frequency front-end module in the above embodiments.

[0047] Specifically, the electronic device is equipped with the RF front-end module described in the above embodiments. It is a communication electronic device designed for mid-to-high frequency communication scenarios such as 5G, Wi-Fi 6E, and IoT private networks. Leveraging the core characteristics of this RF front-end module, such as wideband impedance matching, low-loss transmission, and full-band clutter suppression, it achieves efficient processing and transmission of the device's RF signals. This solves the problems of insufficient bandwidth, low transmission efficiency, and large module size caused by narrowband matching networks in traditional device RF front-ends. The RF front-end module can be implemented using SiP (System-in-Package) or as a single chip. When applied to SiP system-level scenarios, its advantages in miniaturization, low loss, and high integration are even more pronounced.

[0048] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. An impedance transformation circuit, characterized in that, The circuit includes: a single-ended transformer, a first resonant circuit, a second resonant circuit, and a low-frequency suppression circuit, wherein, One end of the primary coil of the single-ended transformer serves as the signal input terminal, and the other end of the primary coil of the single-ended transformer is grounded. One end of the secondary coil of the single-ended transformer serves as the load output terminal, and the other end of the secondary coil of the single-ended transformer is grounded. The first terminal of the low-frequency suppression circuit is connected to one end of the primary coil, the second terminal of the low-frequency suppression circuit is connected to the first terminal and the first port of the first resonant circuit respectively, the third terminal of the low-frequency suppression circuit is grounded, and the second terminal of the first resonant circuit is grounded. The first end of the second resonant circuit is connected to one end of the secondary coil and the second port, respectively, and the second end of the second resonant circuit is grounded.

2. The impedance transformation circuit according to claim 1, characterized in that, The low-frequency suppression circuit includes: a first capacitor and a first inductor, wherein, One end of the first capacitor is connected to one end of the primary coil, and the other end of the first capacitor is connected to one end of the first inductor and the first end of the first resonant circuit, respectively. The other end of the first inductor is grounded.

3. The impedance transformation circuit according to claim 2, characterized in that, The first resonant circuit includes: a second capacitor and a second inductor, wherein, One end of the second capacitor is connected to the other end of the first capacitor, one end of the first inductor, and the first port, respectively. The other end of the second capacitor is connected to one end of the second inductor, and the other end of the second inductor is grounded.

4. The impedance transformation circuit according to claim 1, characterized in that, The second resonant circuit includes: a third capacitor and a third inductor, wherein, One end of the third capacitor is connected to one end of the secondary coil and the second port, respectively. The other end of the third capacitor is connected to one end of the third inductor, and the other end of the third inductor is grounded.

5. The impedance transformation circuit according to claim 1, characterized in that, The single-ended transformer adopts an upper and lower coil structure.

6. The impedance transformation circuit according to claim 2, characterized in that, The first capacitor is also used in conjunction with the single-ended transformer to achieve LC frequency selection.

7. The impedance transformation circuit according to claim 4, characterized in that, The third capacitor is also used in conjunction with the single-ended transformer to participate in target frequency impedance matching.

8. A radio frequency front-end module, characterized in that, include: The impedance transformation circuit according to any one of claims 1-7.

9. An electronic device, characterized in that, include: The radio frequency front-end module as described in claim 8.

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