Surface-mounted radio frequency relay test tool and design method thereof

Abstract

The application discloses a kind of surface-mounted radio frequency relay test tool and its design method, including base, the surface of the base is equipped with installation area and joint installation site, printed board assembly, the printed board assembly is installed in the installation area on base, radio frequency joint, radio frequency joint is set on the joint installation site of base, SMA connector assembly, the SMA connector assembly is inserted in radio frequency joint, for being connected with external test instrument.This application, by the design method of optimization printed board, realize the integration of surface-mounted relay product radio frequency signal output and control signal input, and through the conversion of output interface, without welding can complete surface-mounted radio frequency relay and the connection of test system, completely avoid the damage caused to product in welding and disassembly process, to reduce product scrap rate, simultaneously without welding, also can greatly reduce single test time, improve test efficiency, to meet the full inspection demand of mass production.

Description

Technical Field

[0001] This invention relates to the field of surface-mount radio frequency relay testing technology, and in particular to a surface-mount radio frequency relay testing fixture and its design method. Background Technology

[0002] Radio frequency (RF) relays mainly refer to control devices for microwave transmission and channel selection within a certain frequency range. In recent years, aerospace, military, and other equipment systems have increasingly higher requirements for integration, miniaturization, and high reliability. Surface-mount RF relays have been widely used due to their advantages such as small size, easy integration, and high reliability. The increasing demand for RF relays requires short production cycles, high batch production stability, and strong reliability, which poses a challenge to the assembly and inspection of RF relays, which have relatively complex structures and cumbersome testing processes.

[0003] Due to the different actual application methods of surface-mount RF relays, the products need to be soldered onto the printed circuit board first, and then the control circuit realizes the functions of microwave transmission and channel selection within a certain frequency range. Once soldering is performed during production assembly or factory inspection, not only is the efficiency reduced, but the soldered products cannot be shipped as qualified products, and the production cost increases significantly, which is not conducive to the industrialization of surface-mount RF relay products. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings mentioned above by providing a surface-mount radio frequency relay testing fixture and its design method, thereby improving testing efficiency and reducing production costs.

[0005] To solve the above technical problems, the present invention adopts the following technical solution: a surface-mount radio frequency relay test fixture, comprising: The base has a mounting area and three connector mounting positions on its surface. A printed circuit board assembly, wherein the printed circuit board assembly is mounted in a mounting area on a base; The radio frequency connectors are in the form of three, and the three radio frequency connectors are respectively disposed on the three connector mounting positions of the base; SMA connector assembly, which is plugged into an RF connector for connection to external test instruments; A limiting and fixing component is disposed on the base and located outside the RF connector to enable quick locking and unlocking after the SMA connector assembly is inserted.

[0006] Furthermore, the surface of the printed circuit board assembly is provided with a surface-mount RF relay mounting position, and a dense array of grounding vias is provided around the mounting position. The printed circuit board assembly is made of a low dielectric loss high frequency substrate.

[0007] Furthermore, the inner conductor tail of the RF connector is soldered to the microstrip line pad of the printed circuit board assembly to form a low-loss RF path.

[0008] Furthermore, the SMA connector assembly includes an insulating base on which an SMA connector body is disposed for insertion into an RF connector, and a slot is formed on the surface of the insulating base.

[0009] Furthermore, there are three slots, which are respectively opened on the bottom surface of the base and on two opposite sides, with the opening direction of the bottom slot perpendicular to the opening direction of the two side slots.

[0010] Furthermore, the limiting and fixing assembly includes a limiting seat disposed on the surface of the base, and the limiting seat is located outside the radio frequency connector; The inner cavity of the limiting seat is slidably provided with two symmetrically distributed movable frames, and a spring is provided between the disjoint surfaces of the two movable frames and the inner cavity wall of the limiting seat. The inner cavity of the limiting seat is slidably provided with a slider that slides and fits against the opposing surfaces of the two movable frames. The surface of the slider is provided with a handle that penetrates through and extends to the outside of the limiting seat. Both ends of the movable frames and the surface of the slider are provided with inserts that penetrate and extend to the outside of the limiting seat, and the inserts can be inserted into slots on the surface of the insulating base.

[0011] Furthermore, the limiting seat is a U-shaped hollow seat body, and the surface of the limiting seat has a through hole communicating with the inner cavity, and the handle extends through the through hole to the outside of the limiting seat.

[0012] Furthermore, the surfaces of the two movable frames that are in contact with the slider are inclined surfaces, the slider is an isosceles trapezoidal structure, and the inclined surfaces of the slider surface are adapted to the inclined surfaces of the movable frames.

[0013] A design method for a surface-mount RF relay test fixture, based on any one of the surface-mount RF relay test fixtures described above, wherein the method is as follows: S1. Application of low dielectric loss high frequency substrate: Low dielectric loss high frequency substrate is selected and microstrip lines are made of ultra-thin copper foil to reduce transmission loss. S2. Multi-level matching network stacking design: Lumped capacitors or inductors are embedded inside the multi-layer PCB, and multi-level LC matching networks are formed by stacking them in vertical space to expand the matching bandwidth. S3, Three-dimensional grounding compensation technology: A dense array of grounding vias is arranged around the relay installation area to optimize the via spacing, and combined with the three-dimensional interconnection of the top and bottom ground planes to form a continuous low-impedance ground plane reference. S4. Gradual Microstrip Transition Structure: An impedance-gradual curve transition structure is used to connect the RF relay pins and the microstrip line to reduce impedance abrupt changes and reduce high-frequency reflection loss.

[0014] The beneficial effects of this invention are reflected in: 1. In use, this invention integrates the RF signal output and control signal input of surface-mount relay products through an optimized printed circuit board design method. By converting the output interface, the surface-mount RF relay can be connected to the test system without soldering, completely avoiding damage to the product caused by soldering and desoldering processes, thereby reducing the product scrap rate. At the same time, eliminating the need for soldering can also significantly reduce the single test time and improve test efficiency, thus meeting the full inspection requirements of mass production.

[0015] 2. When in use, the present invention employs a pluggable SMA connector assembly, and with the help of a quick-release limiting and fixing component, it can quickly lock and unlock the SMA connector assembly, allowing for rapid replacement of the SMA connector assembly to adapt to different testing equipment, and significantly reducing test conversion time. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a partial structural schematic diagram of the present invention; Figure 3 This is a schematic diagram of the structure of the SMA connector assembly of the present invention; Figure 4 This is a schematic diagram of the structure of the limiting and fixing component of the present invention; Figure 5 This is a cross-sectional view of the limiting and fixing component of the present invention.

[0017] In the picture: 1. Base; 2. Printed circuit board assembly; 3. RF connector; 4. SMA connector assembly; 41. Insulating base; 42. SMA connector body; 43. Slot; 5. Limiting and fixing components; 51. Limiting seat; 52. Movable frame; 53. Spring; 54. Slider; 55. Handle; 56. Insert block. Detailed Implementation

[0018] 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 a part of the embodiments of the present invention, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. 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.

[0019] Please see Figure 1-5 This invention discloses a surface-mount radio frequency relay test fixture, comprising: The base 1 has a rectangular mounting area and three connector mounting positions on its surface. The base 1 is made of aluminum alloy and provides stable mechanical support and heat dissipation path.

[0020] Printed board assembly 2 is mounted on the rectangular mounting area of ​​the base 1 by screws. The PCB board of the printed board assembly 2 is tightly attached to the base 1 by screws, which not only prevents the PCB board from deforming due to connector plugging or external vibration, but also uses the metal base as a heat sink to dissipate the heat generated when the relay is working. The surface of the printed circuit board assembly 2 is provided with a surface-mount RF relay mounting position, and a dense array of grounding vias is provided around the mounting position. The printed circuit board assembly 2 is made of a low dielectric loss high frequency substrate. It should be noted that a high-quality metal base is the foundation for achieving excellent electromagnetic shielding and multi-point grounding. It can effectively isolate external electromagnetic interference and ensure a perfect connection between the PCB ground plane and the chassis through dense grounding screws, greatly reducing the parasitic effects and noise of high-frequency signals. Secondly, a reasonable base cavity design can avoid interference of structural components on RF traces and ensure the impedance continuity of microstrip transmission lines, thereby allowing the RF relays mounted on the board to perform at their true performance.

[0021] There are three RF connectors 3, and the three RF connectors 3 are respectively set on the three connector mounting positions of the base 1. All three RF connectors 3 are SMA type female connectors. The tail of the inner conductor of the RF connector 3 is soldered to the microstrip line pad of the printed circuit board assembly 2 to form a low-loss RF path.

[0022] SMA connector assembly 4 is plugged into RF connector 3 for connection to external test instruments; SMA connector assembly 4 includes an insulating base 41, on which an SMA connector body 42 is disposed and inserted into the radio frequency connector 3, and a slot 43 is formed on the surface of the insulating base 41. The SMA connector body 42 adopts an SMA type male head, and its inner conductor makes elastic contact with the pin of the surface-mount RF relay under test. There are three slots 43, which are respectively opened on the bottom surface of the base 1 and on two opposite sides. The opening direction of the bottom slot 43 is perpendicular to the opening direction of the two side slots 43.

[0023] Limiting and fixing component 5 is disposed on the base 1 and located on the outside of the RF connector 3, and is used to achieve quick locking and unlocking after the SMA connector assembly 4 is inserted; The limiting and fixing assembly 5 includes a limiting seat 51 disposed on the surface of the base 1. The limiting seat 51 is a U-shaped and hollow seat body, and the limiting seat 51 is located outside the radio frequency connector 3. At the same time, the surface of the limiting seat 51 is provided with a through hole communicating with the inner cavity. It should be noted that the U-shaped limiting seat 51 is fixed to the base 1 by bolts, and its opening faces the direction of the radio frequency connector 3; The inner cavity of the limiting seat 51 is slidably provided with two symmetrically distributed movable frames 52, and a spring 53 is provided between the disjoint surfaces of the two movable frames 52 and the inner cavity wall of the limiting seat 51. The inner cavity of the limiting seat 51 is slidably provided with a slider 54 that slides and fits against the opposing surfaces of the two movable frames 52. The surface of the slider 54 is provided with a handle 55 that passes through and extends to the outside of the limiting seat 51. The handle 55 passes through a through hole on the surface of the limiting seat 51 and extends to the outside of the limiting seat 51. Under the action of the through hole, the handle 55 can move back and forth and drive the slider 54 to move. Meanwhile, the surfaces of the movable frame 52 and the slider 54 that are in contact are inclined surfaces. The slider 54 has an isosceles trapezoidal structure, and the inclined surface of the slider 54 is adapted to the inclined surface of the movable frame 52. Under the action of the inclined surface cooperation, when the handle 55 moves the slider 54 down, it will apply an outward force to the two movable frames 52, forcing the two movable frames 52 to move to the opposite side and compress the spring 53. Both movable frames 52 and the surface of slider 54 are provided with inserts 56 that penetrate and extend to the outside of limit seat 51. The inserts 56 can be inserted into slots 43 on the surface of insulating base 41. When the slider 54 moves down, the insert 56 on the slider 54 will gradually be pulled out from the corresponding slot 43. At the same time, when the two movable frames 52 move to the opposite side, the insert 56 on the movable frame 52 will also be pulled out from the corresponding slot 43. When all three inserts 56 are pulled out, the unlocking is completed.

[0024] Through the above structural settings: 1. In use, by innovatively designing the printed circuit board assembly 2 in the test fixture, the RF signal output and control signal input of the surface-mount relay product are integrated, reducing the size of the test fixture. The test fixture converts the 1 / 2-hole output interface of the surface-mount RF relay into a standard SMA interface, and the 1 / 2-hole input interface into a conventional pin interface. The RF interface in the printed circuit board assembly 2 matches the product's RF output interface and control interface matches the product's control input interface in a one-to-one match, ensuring reliable contact between the product and the fixture during performance testing. This enables performance testing of the surface-mount RF relay during production assembly and factory inspection. The connection between the surface-mount RF relay and the test system can be completed without soldering, completely avoiding damage to the product caused by soldering and desoldering processes, thus reducing the product scrap rate. Furthermore, eliminating the need for soldering significantly reduces the single test time and improves testing efficiency, thereby meeting the full inspection requirements of mass production.

[0025] 2. In use, the handle 55 moves the slider 54, which in turn moves the movable bracket 52, thereby pulling the plug 56 out of the slot 43 and unlocking it. At this time, the SMA connector assembly 4 is pulled out. When inserting the SMA connector assembly 4, first pull the handle 55 to unlock it. At this time, the SMA connector assembly 4 can be inserted into the RF connector 3. After insertion, release the handle 55. At this time, under the action of the spring 53, the slider 54 and the movable bracket 52 return to the initial position, thereby driving the plug 56 to insert into the slot 43, thus locking it. The quick locking and unlocking of the SMA connector assembly 4 can realize the quick replacement of the SMA connector assembly 4, thereby adapting to different test equipment and significantly reducing the test conversion time.

[0026] A design method for a surface-mount RF relay test fixture is as follows: S1. Application of low dielectric loss high frequency substrate: Low dielectric loss high frequency substrate is selected and microstrip lines are made of ultra-thin copper foil to reduce transmission loss. S2. Multi-level matching network stacking design: Lumped capacitors or inductors are embedded inside the multi-layer PCB, and multi-level LC matching networks are formed by stacking them in vertical space to expand the matching bandwidth. S3, Three-dimensional grounding compensation technology: A dense array of grounding vias is arranged around the relay installation area to optimize the via spacing, and combined with the three-dimensional interconnection of the top and bottom ground planes to form a continuous low-impedance ground plane reference. S4. Gradual Microstrip Transition Structure: An impedance-gradual curve transition structure is used to connect the RF relay pins and the microstrip line to reduce impedance abrupt changes and reduce high-frequency reflection loss.

[0027] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0028] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0029] Additionally, "multiple" refers to two or more.

[0030] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A surface-mount radio frequency relay testing fixture, characterized in that, include: The base (1) has an installation area and three connector mounting positions on its surface; Printed board assembly (2), which is mounted in the mounting area on the base (1); Radio frequency connector (3), the number of radio frequency connectors (3) is three, and the three radio frequency connectors (3) are respectively set on the three connector mounting positions of the base (1); SMA connector assembly (4), which is plugged into RF connector (3) for connection to external test instruments; Limiting and fixing component (5), which is disposed on the base (1) and located outside the radio frequency connector (3), is used to achieve quick locking and unlocking after the SMA connector assembly (4) is plugged in.

2. The surface-mount radio frequency relay test fixture according to claim 1, characterized in that: The surface of the printed circuit board assembly (2) is provided with a surface-mount RF relay mounting position, and a dense array of grounding vias is provided around the mounting position. The printed circuit board assembly (2) is made of a low dielectric loss high frequency substrate.

3. The surface-mount radio frequency relay test fixture according to claim 1, characterized in that: The inner conductor tail of the RF connector (3) is soldered to the microstrip pad of the printed circuit board assembly (2) to form a low-loss RF path.

4. The surface-mount radio frequency relay test fixture according to claim 1, characterized in that: The SMA connector assembly (4) includes an insulating base (41), on which an SMA connector body (42) is disposed and inserted into the radio frequency connector (3), and a slot (43) is provided on the surface of the insulating base (41).

5. The surface-mount radio frequency relay test fixture according to claim 4, characterized in that: The number of slots (43) is three, and they are respectively opened on the bottom surface of the base (1) and two opposite sides. The opening direction of the bottom slot (43) is perpendicular to the opening direction of the two side slots (43).

6. A surface-mount radio frequency relay test fixture according to claim 1 or 4, characterized in that: The limiting and fixing assembly (5) includes a limiting seat (51) disposed on the surface of the base (1), and the limiting seat (51) is located outside the radio frequency connector (3); The inner cavity of the limiting seat (51) is slidably provided with two symmetrically distributed movable frames (52), and a spring (53) is provided between the separating surfaces of the two movable frames (52) and the inner cavity wall of the limiting seat (51). The inner cavity of the limiting seat (51) is slidably provided with a slider (54) that slides and fits against the opposite surfaces of the two movable frames (52). The surface of the slider (54) is provided with a handle (55) that penetrates through and extends to the outside of the limiting seat (51). Both ends of the movable frames (52) and the surface of the slider (54) are provided with inserts (56) that penetrate and extend to the outside of the limiting seat (51), and the inserts (56) can be inserted into the slots (43) on the surface of the insulating base (41).

7. The surface-mount radio frequency relay test fixture according to claim 6, characterized in that: The limiting seat (51) is a U-shaped hollow seat body, and the surface of the limiting seat (51) is provided with a through hole communicating with the inner cavity. The handle (55) extends through the through hole to the outside of the limiting seat (51).

8. The surface-mount radio frequency relay test fixture according to claim 6, characterized in that: The surfaces of the two movable frames (52) that are in contact with the slider (54) are inclined surfaces. The slider (54) is an isosceles trapezoidal structure, and the inclined surface of the slider (54) is adapted to the inclined surface of the movable frame (52).

9. A design method for a surface-mount radio frequency relay testing fixture, characterized in that: Based on the surface-mount RF relay test fixture as described in any one of claims 1-8, the method is as follows: S1. Application of low dielectric loss high frequency substrate: Low dielectric loss high frequency substrate is selected and microstrip lines are made of ultra-thin copper foil to reduce transmission loss. S2. Multi-level matching network stacking design: Lumped capacitors or inductors are embedded inside the multi-layer PCB, and multi-level LC matching networks are formed by stacking them in vertical space to expand the matching bandwidth. S3, Three-dimensional grounding compensation technology: A dense array of grounding vias is arranged around the relay installation area to optimize the via spacing, and combined with the three-dimensional interconnection of the top and bottom ground planes to form a continuous low-impedance ground plane reference. S4. Gradual Microstrip Transition Structure: An impedance-gradual curve transition structure is used to connect the RF relay pins and the microstrip line to reduce impedance abrupt changes and reduce high-frequency reflection loss.

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