A surface mount radio frequency load patch having a signal coupling port

Abstract

The application discloses a surface-mounted radio frequency load sheet with a signal coupling port, comprising: an aluminum nitride ceramic substrate, a front conductor circuit, a thick film resistor, a back conductor circuit, a glaze protective film, a dielectric protective film, a product input electrode position mark and a front-back conductor connecting circuit. The radio frequency load sheet is manufactured by using the application, and a signal coupling output electrode is innovatively added on the basis of a traditional radio frequency load sheet. The signal coupling output electrode can be used to monitor the intensity of an input signal, so as to monitor the working state of equipment. The combination function of an existing radio frequency coupler and a radio frequency load is realized, and the demand of miniaturization and cost reduction of equipment is met. Compared with a traditional radio frequency attenuating sheet, only one thick film resistor is used, the product has good heat conduction, the circuit layout is simple, the manufacturing process is simplified, and the production cost is greatly reduced.

Description

[0001] The present application relates to a kind of multifunctional ceramic substrate thick film radio frequency device for mobile communication and its preparation method, more particularly to a kind of surface-mounted load sheet with signal coupling port and its preparation method, belong to mobile communication device technical field. BACKGROUND

[0002] The power amplifier circuit in mobile communication base station is all radio frequency signal coupler extraction small signal to monitor the state of base station power amplifier, and through the isolation port of circulator, external high-power radio frequency load sheet is connected to absorb the reverse input power in radio frequency output end (such as external antenna etc.), when base station work fails, the intensity of coupled signal is judged, and the device is protected.

[0003] The base station power amplifier using the above traditional scheme needs to use coupler to connect radio frequency load with signal circulator, and needs to occupy larger space on board. Moreover, 2 independent devices are configured on the circuit board, and the comprehensive cost of power amplifier is higher. With the development of 5G mobile communication, the space and energy consumption of base station are required to be higher and higher. In order to reduce the space and energy consumption of base station and the comprehensive cost of base station, the space of circuit board and the comprehensive cost of components should be minimized. Based on the traditional technical scheme, radio frequency attenuator can be connected to the model isolation port of circulator to monitor signal and protect the device. However, radio frequency attenuator usually adopts T-shaped structure or π-shaped structure circuit. It is a radio frequency network device with at least three resistors. The traditional radio frequency attenuator has more than 3 resistors printed on a ceramic substrate, and the effective heat dissipation area of each resistor is relatively small, which affects the heat dissipation capacity of the product. At the same time, the radio frequency attenuator has 3 or more resistors on the product, and the production process is relatively complex, which leads to high product cost.

[0004] In addition, in order to reduce signal reflection and accurately control radio frequency signal attenuation value, the 3 resistors of T-shaped or π-shaped network need to be laser adjusted in the present technical field, so that the range of resistance is in an accurate range, usually in a tolerance range of 2%-5%. This leads to further increase of production cost. SUMMARY

[0005] The technical problem solved by the present application is to provide a surface-mounted radio frequency load sheet with signal coupling port and its manufacturing method, which is applied to the field of radio frequency communication. It has the functions of signal coupling monitoring and radio frequency load absorbing reflected power, and plays the role of base station state monitoring and protecting the device from damage in abnormal condition. Moreover, the load sheet is integrated on a ceramic substrate, which is convenient for base station power amplifier layout, reduces the space and cost of equipment. In addition, the radio frequency load sheet provided by the present application has only one thick film resistor, and the thick film resistor has a larger contact area with aluminum nitride ceramic substrate, which further improves the heat dissipation function of the product, improves the stability of the product and reduces the cost.

[0006] To solve the above technical problems, one technical solution adopted by the present application is as follows:

[0007] A surface-mounted radio frequency load sheet with a signal coupling port comprises: an aluminum nitride ceramic substrate, a thick film resistor, a front conductor circuit, a back conductor circuit, and a front-back conductor connecting circuit.

[0008] The aluminum nitride ceramic substrate is a square structure ceramic sheet, used to carry the front conductor circuit, the back conductor circuit, the front-back conductor connecting circuit, and the thick film resistor.

[0009] The thick film resistor is arranged on the front surface of the aluminum nitride ceramic substrate.

[0010] The back conductor circuit comprises a signal coupling output electrode, a signal input electrode, and a working ground.

[0011] The back conductor circuit serves as a welding surface of the surface-mounted radio frequency load sheet with a signal coupling port, used for welding with a corresponding electrode welding surface of an external PCB circuit board.

[0012] The radio frequency load sheet made by the present application, based on the traditional radio frequency load sheet, innovatively adds a signal coupling output port, which can be used to monitor the intensity of the input signal and thus the working state of the equipment.

[0013] Further, the front conductor circuit comprises a front signal coupling port, a front input conductor circuit, and a front working ground.

[0014] Further, the front signal coupling port is a rectangular structure, located at the upper right corner of the front of the aluminum nitride ceramic substrate; a blank area is provided between the front signal coupling port and the front input conductor circuit, and no conductor is connected between the front signal coupling port and the front input conductor circuit; the blank area serves as a signal coupling area to couple the input signal to the front signal coupling port.

[0015] The thick film resistor and the front conductor circuit of the aluminum nitride ceramic substrate have an overlapping area, the thick film resistor is a rectangular structure resistor film layer, and the resistor paste is printed on the front design area of the ceramic substrate by a screen printing process; in the overlapping area of the thick film resistor and the front conductor circuit, the thick film resistor paste covers the conductor circuit, and after drying and high-temperature sintering, a reliable connection is formed.

[0016] Further, the front input conductor circuit is a T-shaped structure conductor circuit, and a rectangular structure conductor circuit is connected to the end of the T-shaped structure conductor circuit, and the rectangular structure conductor circuit is electrically connected to the input signal connection circuit.

[0017] Further, the front and back conductor connection circuits include: working ground connection circuit, coupling signal connection circuit, input signal connection circuit. The front and back conductor connection circuits are four metal cylinders made by pre-machining four ceramic through holes in the ceramic substrate and filling silver conductor paste in the ceramic through holes by a screen printing process, and then drying and high-temperature sintering. They are respectively located inside the through holes of the aluminum nitride ceramic substrate. The conductor connection circuits are respectively connected to the conductor circuits on the front and back of the ceramic substrate to form a circuit channel for radio frequency signals.

[0018] Further, the signal coupling output electrode, the signal input electrode, and the working ground are all provided on the back of the aluminum nitride ceramic substrate and are electrically connected to the front and back conductor connection circuits filled in the through holes of the aluminum nitride ceramic substrate.

[0019] Further, the radio frequency load sheet further includes an enamel protective film for protecting the thick film resistor and the front conductor circuit, the enamel protective film covers the thick film resistor and the front conductor circuit, and the edge of the enamel protective film is recessed by 0.1 mm from the edge of the aluminum nitride ceramic substrate. The enamel protective film is printed by a thick film screen printing process, and after drying and high-temperature sintering, the enamel paste with an expansion coefficient matching the resistance of the radio frequency load sheet is covered on the thick film resistor and the front conductor circuit to protect the resistance and the front conductor circuit from external damage.

[0020] Further, the enamel protective film is further covered by a dielectric protective film, the edge of which is inwardly recessed from the edge of the aluminum nitride ceramic substrate by 0.1 mm, and the dielectric protective film completely covers the enamel protective film. The dielectric protective film is printed on the enamel protective film by a thick film printing process, and is cured and shaped by drying and sintering processes, and has acid and alkali corrosion resistance, so as to further protect the radio frequency load sheet from external environment corrosion and damage.

[0021] Further, the dielectric protective film is further provided with a product input electrode position mark at a position close to the right side center and about 2 mm away from the ceramic edge, for automatic recognition and positioning of the machine in subsequent product packaging and welding processes. The product input electrode position mark is preferably a mark dot, which is located on the upper surface of the load sheet, close to the right side center and about 2 mm away from the ceramic edge. In this way, the machine can automatically recognize the input electrode position of the product during product packaging and customer welding, so as to prevent the product from being positioned in the wrong direction during product packaging and welding, which may cause the load sheet to be installed in the wrong direction, and affect the normal operation of the power amplifier.

[0022] Further, the surface-mounted radio frequency load sheet is used in a reverse patch manner and is welded with the PCB board, and the signal coupling output electrode, the signal input electrode and the working ground on the reverse side of the radio frequency load sheet correspond to the electrode positions with corresponding functions on the PCB board.

[0023] Further, the characteristic impedance of the radio frequency load sheet is 50 ohms, the working frequency is DC-6.0GHZ, the input end reflection coefficient is greater than 20db, and the coupling end coupling coefficient is 30db.

[0024] In actual application, the size of the load sheet is preferably 6.35mm*6.35mm*1.0mm. The thick film resistance layer can be formed by printing metal oxide resistance paste on the aluminum nitride ceramic substrate, and then curing and shaping after drying and sintering, and together with the front conductor circuit and the reverse conductor circuit, forms a microstrip radio frequency circuit. In the selection of parameters, the input end reflection coefficient is greater than 20db and the coupling end coupling coefficient is 30db in the DC-6.0Ghz working frequency range. The average power of the load sheet is preferably 150W.

[0025] Further, the front signal coupling port and the front input conductor circuit, the front working ground is formed by printing silver conductor paste on the ceramic substrate at one time, and printing according to the pre-designed circuit layout structure size, drying, high temperature sintering and curing. The front input conductor circuit and the ceramic substrate with a certain thickness and dielectric constant together form a radio frequency network to realize the functions of radio frequency signal coupling and input circuit matching, so as to achieve the radio frequency performance indicators of the product. The front signal coupling port and the front input conductor circuit part mainly serve as a signal coupler. The front input conductor circuit part mainly serves as an input impedance matching circuit to realize the characteristic impedance matching of the input end of the radio frequency load sheet and achieve the input reflection coefficient index greater than 20db.

[0026] Further, the front conductor circuit of the ceramic substrate of the radio frequency load sheet also includes a front working ground connected with the rectangular thick film resistor. The front working ground and other conductor circuit patterns on the front of the ceramic substrate are printed with silver conductor paste on the front of the ceramic substrate by one-time screen printing process, and are cured into a front conductor circuit by drying and high temperature sintering process. Each functional part of the front conductor circuit is electrically connected with its corresponding front and back conductor connection circuit, thereby forming the electrical connection between the front conductor circuit and the back conductor circuit, and realizing the transmission function of the radio frequency signal.

[0027] Further, the back of the ceramic substrate of the radio frequency load sheet is printed with silver conductor paste and cured into shape after drying and high temperature sintering, which serves as a signal coupling output electrode, a signal input electrode and a working ground, respectively, as a signal coupling output electrode, a signal input electrode and a signal working ground of the radio frequency load sheet. The signal input electrode is connected to the front input conductor circuit on the front of the ceramic substrate through the input signal connection circuit penetrating the front and back conductor connection circuit of the ceramic substrate; the signal coupling output electrode is connected to the front signal coupling port on the front of the ceramic substrate through the coupling signal connection circuit penetrating the ceramic substrate; and the signal working ground is connected to the front working ground on the front of the ceramic substrate through the two working ground connection circuits penetrating the ceramic substrate.

[0028] Further, the signal input electrode, the signal coupling output electrode and the signal working ground on the back of the load sheet ceramic substrate also need to be subjected to metal surface treatment and then electroplated on the surface to prevent electrode oxidation and environmental erosion, improve electrode strength and product weldability, and further improve the effect of customer application and the adaptability of the product.

[0029] Further, the RF load sheet integrates RF load function and RF signal coupling function on a 6.35mm*6.35mm*1.0mm aluminum nitride ceramic substrate, and the front side of the RF load sheet is not connected to the circuit by the conductor on the four sides of the aluminum nitride ceramic substrate. There is only a signal connection electrode and a working ground on the bottom of the product. The working ground also serves as the main heat conduction interface of the RF load, and the area accounts for more than 90% of the entire product area. The heat generated by the reflected power absorbed by the load resistor is conducted to the corresponding electrode of the PCB circuit board soldered to the back of the product through the front conductor circuit on the upper surface of the ceramic, the front and back conductor connection circuit inside the ceramic via, and the back conductor circuit on the back of the RF load sheet. The heat is quickly conducted to the heat sink of the power amplifier.

[0030] Further, the surface-mounted RF load sheet with a coupling port can be used for mobile communication, microwave communication and other wireless communication. It can be used for existing 4G mobile communication or the latest 5G mobile communication. It can be used as a signal coupler with RF load, or it can be used as a RF load or a signal coupler alone. The RF signal coupling coefficient is 30db. BRIEF DESCRIPTION OF DRAWINGS

[0031] The above description is only a summary of the scheme of the present application. In order to more clearly illustrate the technical scheme of the present application, and the content of the specification can be implemented, the following will be described by the embodiments of the present application and combined with the drawings.

[0032] Figure 1 is the front structure layout diagram of the surface-mounted RF load sheet with a signal coupling port of the present application.

[0033] Figure 2 is the left side A-A cross-sectional view of the surface-mounted RF load sheet with a signal coupling port of the present application.

[0034] Figure 3 is the right side B-B cross-sectional view of the surface-mounted RF load sheet with a signal coupling port of the present application.

[0035] Figure 4 is the bottom view of the surface-mounted RF load sheet with a signal coupling port of the present application.

[0036] Figure 5 is the top view of the surface-mounted RF load sheet with a signal coupling port of the present application.

[0037] The parts in the drawings are described as follows:

[0038] 1 - aluminum nitride ceramic substrate 2 - thick film resistor 3 - front conductor circuit

[0039] 4 - back conductor circuit 5 - enamel protective film 6 - dielectric protective film

[0040] 7 - product input electrode position mark 8 - front and back conductor connection circuit

[0041] 3A - front signal coupling port 3B - front input conductor circuit

[0042] 3C - front working ground 4A - signal coupling output electrode

[0043] 4B - signal input electrode 4C - working ground

[0044] 8A, 8B - working ground connection circuit 8C - coupling signal connection circuit

[0045] 8D - input signal connection circuit DETAILED DESCRIPTION

[0046] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. In order to make the advantages and features of the present application better understood by those skilled in the art, the scope of protection of the present application is defined more clearly and explicitly.

[0047] In some embodiments, as shown in Figures 1-5 A surface-mounted radio frequency load sheet with a signal coupling port, the substrate of the radio frequency load sheet is preferably a piece of 6.35mm*6.35mm*1.0mm aluminum nitride ceramic substrate 1, the front of the radio frequency load sheet is provided with a thick film resistor 2, a front conductor circuit 3, and two ceramic through holes with a certain interval and arranged side by side are pre-processed on the left and right sides of the aluminum nitride ceramic substrate 1. Inside the four ceramic through holes, silver conductor paste is filled through the metal paste hole filling process, and is solidified and shaped through the drying and high temperature sintering process to form a front and back conductor connection circuit 8. The front and back conductor connection circuit 8 includes working ground connection circuits 8A, 8B; coupling signal connection circuits 8C, input signal connection circuits 8D, which respectively undertake their own signal connection functions.

[0048] The thick film resistor 2 is a rectangular metal oxide resistor thin layer, and the length and width of the resistor area are preferably about 5.3mm*4.0mm. The resistor thin layer is formed by screen printing metal oxide resistor paste on the front of the aluminum nitride ceramic substrate, and is solidified by drying and high temperature sintering. The present application only sets one thick film resistor, and the manufacturing process is simple, the production cost is low compared with the prior art, and the heat dissipation effect is good.

[0049] The front conductor circuit 3 includes a front signal coupling port 3A, a front input conductor circuit 3B and a front working ground 3C. The front conductor circuit 3 is formed by screen printing a layer of metal silver paste thick film layer once and solidified by drying and high temperature sintering process. The outer edge of the front conductor circuit 3 and the thick film resistor 2 is retracted inwardly from the side edge of the aluminum nitride ceramic substrate 1 by no less than 0.2mm, preventing the thick film resistor 2 and the front conductor circuit 3 from aligning with the ceramic edge of the aluminum nitride ceramic substrate 1, so that the thick film resistor 2 and the front conductor circuit 3 lose protection on the side of the load sheet, resulting in the subsequent process affecting the product performance.

[0050] In some embodiments, the structure of the front conductor circuit 3 is as shown in the attached Figure 1 The thick film resistor 2 and the front conductor circuit 3 are overlapped in the pattern as shown in the attached Figure 1 The overlapped width is about 1mm. Moreover, the thick film resistor 2 covers the overlapped area of the front conductor circuit 3. The front conductor circuit 3 is made first, and then the thick film resistor 2 is made, so as to improve the resistance stability of the thick film resistor 2. The influence of the subsequent high temperature sintering process on the resistance after the thick film resistor 2 is made is prevented, so as to cause the change of product performance.

[0051] The front conductor circuit 3 layout scheme in the embodiment can effectively expand the area of the thick film resistor 2 and maximize the heat conduction capacity of the product. The front input conductor circuit 3B and the front working ground 3C are respectively arranged on the left and right sides of the thick film resistor 2, and the front working ground 3C is a long strip structure and fully contacts the left side of the thick film resistor 2, so as to improve the reliability of grounding. In the embodiment, the front input conductor circuit 3B is a T-shaped silver conductor circuit, and a rectangular silver conductor circuit is further connected to the end of the T-shaped structure. The structure of the front input conductor circuit can optimize the input impedance characteristics of the load sheet and form an input impedance matching circuit. The input reflection coefficient of the RF load sheet is greater than 20db in the working frequency range of DC-6.0Ghz. A rectangular silver conductor thick film layer is arranged at the upper right corner of the front of the ceramic substrate to form a front signal coupling port. The RF signal at the input end is coupled to the front signal coupling port 3A through space and ceramic medium, and the signal is transmitted to the signal coupling output electrode 4A on the back of the RF load sheet through the coupling signal connection circuit 8C connected thereto.

[0052] As shown in the attached Figure 2 , Figure 3The image shows cross-sectional views AA and BB on the left and right sides of the RF load sheet. A reverse conductor circuit 4 is provided on the reverse side of the aluminum nitride ceramic substrate 1. A glaze protective film 5 is provided on top of the thick film resistor 2 and the front conductor circuit 3. A dielectric protective film 6 is provided on top of the glaze protective film 5. The edges of the glaze protective film 5 and the dielectric protective film 6 are completely aligned and completely cover the upper surface of the thick film resistor 2 and the front conductor circuit 3 to protect the thick film resistor layer and the front conductor circuit layer. Approximately 2mm from the edge of the ceramic substrate, at the symmetrical center position on the top of the dielectric protective film 6, there is a product input electrode position mark 7. This mark is formed by screen printing circular white ink dots, which are then dried and cured. This facilitates identification during subsequent product testing, packaging, and soldering positioning.

[0053] like Figure 4 As shown, the reverse conductor circuit 4 of the RF load chip includes three parts: a signal coupling output electrode 4A, a signal input electrode 4B, and a signal ground 4C. When the customer applies the above-mentioned three electrodes of the reverse conductor circuit 4 to the corresponding electrode positions on the PCB board, so that the load can absorb the reflected signal power from the power amplifier output terminal. By monitoring the signal strength of the signal coupling output electrode, the operating status of the base station can be monitored.

[0054] In some embodiments, the reverse conductor circuit 4 of the RF load sheet is made of silver conductor paste that is screen-printed in one step, dried, sintered at high temperature, and then solidified. After surface treatment to remove contaminants acquired during production, a nickel layer is electroplated, followed by a tin layer. This process prevents oxidation of the silver conductor and improves the solderability and stability of the product.

[0055] Figure 5 This is a top view of the RF load sheet described in this invention, wherein the dielectric protective film 6 is formed by screen printing dielectric paste, followed by drying and sintering for curing. The product input electrode position mark 7 is a product mark formed by screen printing ink dots on the dielectric protective film 6 after curing, followed by drying and high-temperature sintering for curing.

[0056] In summary, the technical scheme of the present application, through specially designed front conductor circuit 3 and back conductor circuit 4, sets a radio frequency thick film load 2 on the front surface of the aluminum nitride ceramic substrate 1, and sets a specially structured front conductor circuit 3 on the front surface of the aluminum nitride ceramic substrate 1, that is, innovatively adds a front and back conductor signal coupling circuit part on the basis of the conventional radio frequency load circuit, thereby realizing the radio frequency load function and adding the radio frequency signal coupling function. By setting a radio frequency matching circuit in the input circuit part of the conventional radio frequency load, the input end impedance matching performance of the radio frequency load sheet is optimized, so that the radio frequency characteristics of the radio frequency load sheet made by using the technical scheme can realize excellent input end reflection coefficient index: in the working frequency range of DC-6.0Ghz, the input end reflection coefficient is greater than 20db, and the product coupling coefficient is 30db.

[0057] The above scheme is a detailed description of the technical scheme of the present application in combination with the preferred scheme, and cannot be considered as the specific implementation of the present application limited to these descriptions. For ordinary skilled persons in the field to which the present application pertains, simple deductions and substitutions can be made without departing from the concept of the present application, and should be regarded as the protection scope of the present application.

Claims

1. A surface-mount RF load chip with a signal coupling port, characterized in that, include: Aluminum nitride ceramic substrate (1), thick film resistor (2), front conductor circuit (3), back conductor circuit (4), front and back conductor connection circuit (8); The aluminum nitride ceramic substrate (1) is a square-structured ceramic sheet used to support the front conductor circuit (3), the back conductor circuit (4), the front and back conductor connection circuit (8), and the thick film resistor (2); the aluminum nitride ceramic substrate (1) has 4 cylindrical through holes, and the front and back conductor connection circuit (8) is made by filling the 4 cylindrical through holes with metal paste and then sintering and solidifying it, and is used to connect the front conductor circuit (3) and the back conductor circuit (4); The thick film resistor (2) is disposed on the front side of the aluminum nitride ceramic substrate (1); The reverse conductor circuit (4) includes a signal coupling output electrode (4A), a signal input electrode (4B), and a working ground (4C); The reverse conductor circuit (4) serves as the welding surface of the surface-mount RF load sheet with signal coupling port for welding to the corresponding electrode welding surface of the external PCB circuit board. The front conductor circuit (3) includes a front signal coupling port (3A) and a front input conductor circuit (3B) that serve as a signal coupler; Each functional part of the front conductor circuit (3) is electrically connected to its corresponding front and back conductor connection circuits (8), thereby forming an electrical connection between the front conductor circuit (3) and the back conductor circuit (4).

2. The surface-mount RF load chip with a signal coupling port according to claim 1, characterized in that, The front conductor circuit (3) also includes a front working ground (3C); the front signal coupling port (3A), the front input conductor circuit (3B), and the front working ground (3C) are all located on the front side of the aluminum nitride ceramic substrate (1); the front and back conductor connection circuit (8) includes working ground connection circuits (8A) and (8B); coupling signal connection circuit (8C) and input signal connection circuit (8D); the front input conductor circuit (3B) is electrically connected to the thick film resistor (2) and the input signal connection circuit (8D) respectively, the front working ground (3C) is electrically connected to the thick film resistor (2) and the working ground connection circuits (8A) and (8B) respectively, and the front signal coupling port (3A) is electrically connected to the coupling signal connection circuit (8C).

3. The surface-mount RF load chip with a signal coupling port according to claim 2, characterized in that, The front signal coupling port (3A) is a rectangular structure located at the upper right corner of the front side of the aluminum nitride ceramic substrate (1); a blank area is provided between the front signal coupling port (3A) and the front input conductor circuit (3B), and there is no conductor connection between the front signal coupling port (3A) and the front input conductor circuit (3B); the blank area serves as a signal coupling area to couple the input signal to the front signal coupling port (3A).

4. The surface-mount RF load chip with a signal coupling port according to claim 2, characterized in that, The front input conductor circuit (3B) is a T-shaped conductor circuit, and a rectangular conductor circuit is connected to the end of the T-shaped conductor circuit. The rectangular conductor circuit is electrically connected to the input signal connection circuit (8D).

5. The surface-mount RF load chip with a signal coupling port according to claim 1, characterized in that, The signal coupling output electrode (4A), signal input electrode (4B), and working ground (4C) are all located on the reverse side of the aluminum nitride ceramic substrate (1) and are electrically connected to the front and back conductor connection circuit (8) filled in the perforations of the aluminum nitride ceramic substrate.

6. The surface-mount RF load chip with a signal coupling port according to claim 1, characterized in that, It also includes a glaze protective film (5) for protecting the thick film resistor (2) and the front conductor circuit (3). The glaze protective film (5) covers the thick film resistor (2) and the front conductor circuit (3), and its edge is recessed 0.1 mm from the edge of the aluminum nitride ceramic substrate (1).

7. The surface-mount RF load chip with a signal coupling port according to claim 6, characterized in that, The enamel protective film (5) is further covered with a dielectric protective film (6), the edge of which is recessed 0.1 mm from the edge of the aluminum nitride ceramic substrate (1), completely covering the enamel protective film (5).

8. The surface-mount RF load chip with a signal coupling port according to claim 7, characterized in that, The dielectric protective film (6) is provided with a product input electrode position mark (7) about 2 mm away from the right edge of the aluminum nitride ceramic substrate (1) near the center on the right side. This mark is used for automatic machine identification and positioning during the subsequent product packaging machine welding process.

9. The surface-mount RF load chip with a signal coupling port according to claim 1, characterized in that... The surface-mount RF load cell is soldered to the PCB board using a reverse-side mounting method, and the signal coupling output electrode (4A), signal input electrode (4B), and working ground (4C) on the reverse side of the RF load cell correspond to the corresponding functional electrode positions on the PCB board.

10. The surface-mount RF load chip with a signal coupling port according to claim 1, characterized in that, The characteristic impedance of the RF load chip is 50 ohms, the operating frequency is DC-6.0GHz, the input reflection coefficient is greater than 20dB, and the coupling coefficient at the coupling end is 30dB.

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