Fixture for radio frequency test of microwave device

Abstract

The utility model provides a microwave device radio frequency test clamp comprising a fixed pedestal, a PCB copper-clad plate, a conductive adhesive film, a chip positioning frame and two radio frequency joints, and the two radio frequency joints, a coplanar waveguide line input end on the PCB copper-clad plate, a chip pad and a coplanar waveguide line output end form a test path. A chip pin of a microwave device to be tested is downwards placed into the chip positioning groove, and after the chip is firmly fixed, the microwave device can be electrified for testing. According to the utility model, the two radio frequency connectors are respectively arranged on the two opposite sides of the fixed base, one radio frequency connector is electrically connected with the input end of the coplanar waveguide wire, the other radio frequency connector is electrically connected with the output end of the coplanar waveguide wire, the distance between the two radio frequency connectors is shorter, the loss of radio frequency signals on the coplanar waveguide wire is smaller, and the radio frequency signals are more stable. And the chip positioning frame is provided with the chip positioning groove capable of limiting the chip of the microwave device, so that the stability of the chip in the test period is ensured, and a relatively accurate radio frequency test result is obtained.

Description

Technical Field

[0001] The utility model belongs to the technical field of radio frequency testing fixtures, and in particular relates to a microwave device radio frequency testing fixture. Background Art

[0002] Common microwave devices include microwave oscillators, power amplifiers, mixers, detectors, microwave antennas, microwave transmission lines, etc. Microwave RF chips are the core devices of microwave devices, which are used to realize the generation, mixing, power amplification and other functions of microwave RF signals. Microwave RF chips play a key role in signal processing, and their performance indicators such as gain and return loss need to be tested. Since there are a large number of microwave RF devices in the communication field, it is very necessary to accurately perform RF testing of microwave devices for large-scale mass production of microwave RF devices. The test fixture in the prior art has poor contact with the chip, and its signal transmission circuit loss is large. Errors will inevitably be introduced during the test process, which may lead to inaccurate device test results. Utility Model Content

[0003] The utility model provides a fixture for radio frequency testing of microwave devices, aiming at reducing signal loss and making test results more accurate.

[0004] To achieve the above object, the technical solution adopted by the utility model is: to provide a fixture for radio frequency testing of microwave devices, comprising:

[0005] Fixed base;

[0006] A PCB copper-clad plate is arranged on the upper surface of the fixed base, and the PCB copper-clad plate has a chip pad, a coplanar waveguide line input end and a coplanar waveguide line output end, and the coplanar waveguide line input end and the coplanar waveguide line output end are arranged on opposite sides of the PCB copper-clad plate, and are electrically connected to the chip pad respectively;

[0007] A conductive adhesive film is provided on the upper surface of the PCB copper clad plate;

[0008] A chip positioning frame is provided on the upper surface of the conductive adhesive film, the chip positioning frame is provided with a chip positioning groove which passes through the upper and lower parts, and the chip positioning groove corresponds to the chip pad in the upper and lower parts; and

[0009] Two radio frequency connectors are arranged on opposite sides of the fixed base, wherein one of the radio frequency connectors is electrically connected to the input end of the coplanar waveguide line, and the other radio frequency connector is electrically connected to the output end of the coplanar waveguide line.

[0010] In a possible implementation, the microwave device radio frequency test fixture further includes a pressure cover, and the pressure cover is detachably disposed above the chip positioning frame.

[0011] In a possible implementation, the pressure cover is further provided with an elastic pressure block corresponding to the chip positioning groove.

[0012] In a possible implementation, a positioning pin is further provided on the gland.

[0013] In a possible implementation, the fixed base is provided with a first fixing hole and a second fixing hole, the first fixing hole is a through hole, the second fixing hole at least passes through the upper surface of the fixed base, and the second fixing hole is a threaded hole; the chip positioning frame is provided with a third fixing hole corresponding to the second fixing hole, and the PCB copper clad plate is provided with a fourth fixing hole corresponding to the second fixing hole, and the third fixing hole and the fourth fixing hole are both through holes.

[0014] In a possible implementation, a nickel-gold layer is provided on the upper surface of the PCB copper-clad board, and the thickness of the nickel-gold layer is greater than 0.05 μm.

[0015] In a possible implementation, the PCB copper-clad plate is further provided with a plurality of pin insertion holes, and inner walls of the pin insertion holes are provided with a copper material layer.

[0016] In a possible implementation manner, the radio frequency connector is an SMA radio frequency connector.

[0017] In a possible implementation, a guiding slope is formed on an inner wall of an upper portion of the chip positioning groove.

[0018] In a possible implementation manner, the radio frequency connector is connected to the corresponding coplanar waveguide wire input end or the coplanar waveguide wire output end through soldering.

[0019] Compared with the prior art, the microwave device radio frequency test fixture provided by the utility model has the following beneficial effects:

[0020] The microwave device radio frequency test fixture provided by the utility model comprises a fixed base, a PCB copper-clad plate, a conductive adhesive film, a chip positioning frame and two radio frequency connectors. When in use, the fixed base can be fixed on a seismic isolation platform or other operating platform, and the two radio frequency connectors, the coplanar waveguide input end on the PCB copper-clad plate, the chip pad and the coplanar waveguide output end form a test path. The chip pins of the microwave device to be tested are placed downward into the chip positioning groove, so that the chip pins are connected to the chip pads. After the chip is firmly fixed, power is turned on for testing. In the utility model, the two radio frequency connectors are respectively arranged on opposite sides of the fixed base, one of the radio frequency connectors is electrically connected to the coplanar waveguide input end, and the other radio frequency connector is electrically connected to the coplanar waveguide output end. The distance between the two radio frequency connectors is short, and the loss of the radio frequency signal on the coplanar waveguide is small. The chip positioning frame has a chip positioning groove that can limit the chip of the microwave device, and the chip pad has good contact with the chip, and the test loss is small, which helps to ensure the stability of the chip during the test, thereby obtaining a more accurate radio frequency test result. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the structure of a fixture for radio frequency testing of microwave devices provided in one embodiment of the utility model;

[0022] Figure 2 A fixing base and two radio frequency connectors in a fixture for radio frequency testing of microwave devices provided in one embodiment of the utility model;

[0023] Figure 3 This is a schematic diagram of the structure of a PCB copper-clad plate in one embodiment of the utility model;

[0024] Figure 4 for Figure 3 A partial enlarged view of the middle A part;

[0025] Figure 5 This is a schematic diagram of the structure of a gland in one embodiment of the utility model;

[0026] Description of reference numerals:

[0027] 1. Fixture for RF testing of microwave devices;

[0028] 10. Fixed base; 11. First fixing hole; 12. Second fixing hole;

[0029] 20. PCB copper clad board; 21. Coplanar waveguide input terminal; 22. Chip pad; 221. Pin insertion hole; 23. Coplanar waveguide output terminal; 24. Fourth fixing hole; 25. Power pad;

[0030] 30. Chip positioning frame; 31. Chip positioning groove; 32. Third fixing hole;

[0031] 40. RF connector;

[0032] 50. Pressure cover; 51. Elastic pressure block; 52. Positioning pin. DETAILED DESCRIPTION

[0033] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] It should be noted that when an element is referred to as being "fixed to", "fixed" or "fixedly disposed" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" or "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. When an element is referred to as being "set to" or "disposed on" another element, it may be directly on the other element or there may be a central element. "Multiple" refers to two or more quantities. "At least one" refers to one or more quantities. "Several" refers to one or more quantities.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0036] Please also read Figures 1 to 5 , the fixture 1 for radio frequency testing of microwave devices provided in an embodiment of the utility model is described below.

[0037] See also Figure 1 The utility model provides a fixture 1 for radio frequency testing of microwave devices, comprising a fixed base 10, a PCB copper clad plate 20, a conductive adhesive film, a chip positioning frame 30 and two radio frequency connectors 40, wherein the PCB copper clad plate 20 is arranged on the upper surface of the fixed base 10, and the PCB copper clad plate 20 has a chip pad 22, a coplanar waveguide line input end 21 and a coplanar waveguide line output end 23, the coplanar waveguide line input end 21 and the coplanar waveguide line output end 23 are arranged on opposite sides of the PCB copper clad plate 20, and are respectively electrically connected to the chip pad 22; the conductive adhesive film is arranged on the upper surface of the PCB copper clad plate 20; the chip positioning frame 30 is arranged on the upper surface of the conductive adhesive film, and the chip positioning frame 30 is provided with a chip positioning groove 31 which passes through from top to bottom, and the chip positioning groove 31 corresponds to the chip pad 22 from top to bottom; the two radio frequency connectors 40 are respectively arranged on opposite sides of the fixed base 10, wherein one radio frequency connector 40 is electrically connected to the coplanar waveguide line input end 21, and the other radio frequency connector 40 is electrically connected to the coplanar waveguide line output end 23.

[0038] Compared with the prior art, the microwave device radio frequency test fixture 1 provided by the embodiment of the utility model has the following beneficial effects:

[0039] The fixture 1 for radio frequency testing of microwave devices provided by the embodiment of the utility model comprises a fixed base 10, a PCB copper-clad plate 20, a conductive adhesive film, a chip positioning frame 30 and two radio frequency connectors 40. When in use, the fixed base 10 can be fixed on a seismic isolation platform or other operating platform. The two radio frequency connectors 40, the coplanar waveguide input end 21 on the PCB copper-clad plate 20, the chip pad 22 and the coplanar waveguide output end 23 form a test path. The chip pins of the microwave device to be tested are placed downward into the chip positioning groove 31, so that the pins of the chip are connected to the chip pads 22. After the chip is firmly fixed, power is turned on for testing. In the embodiment of the utility model, two RF connectors 40 are respectively arranged on opposite sides of the fixed base 10, one of the RF connectors 40 is electrically connected to the coplanar waveguide line input end 21, and the other RF connector 40 is electrically connected to the coplanar waveguide line output end 23. The distance between the two RF connectors 40 is short, and the loss of the RF signal on the coplanar waveguide line is small. The chip positioning frame 30 has a chip positioning groove 31 that can limit the chip of the microwave device, which helps to ensure the stability of the chip during the test, thereby obtaining a more accurate RF test result.

[0040] In this embodiment, the fixed base 10 is used to provide a supporting and fixing position for various components installed thereon. The fixed base 10 can be fixed on a table top such as an operating table when in use. To facilitate fixation, a clamp can be set on the table top such as an operating table to firmly clamp the fixed base 10.

[0041] The PCB copper clad board 20 preferably adopts ROS4350 material, and the number of board layers can be specifically 2. The PCB copper clad board 20 is provided with a chip pad 22, a coplanar waveguide line input terminal 21 and a coplanar waveguide line input terminal 21. The surface of the chip pad 22 can be treated with nickel-gold immersion, and the thickness of the nickel-gold layer is greater than 0.05 microns to ensure good welding between the power supply line and the PCB copper clad board 20, and avoid the occurrence of cold welding and short circuit.

[0042] The PCB copper clad board 20 can be connected to the fixed base 10 by welding, screw connection, bonding, etc. When screw connection is adopted, a fixing hole (specifically the fourth fixing hole 24) for the bolt to pass through needs to be opened on the PCB copper clad board 20.

[0043] The material of the chip positioning frame 30 is preferably aluminum, and the surface is sandblasted and oxidized black. The chip positioning frame 30 is used to accommodate and limit the chip to prevent the chip from moving during testing. In order to further improve the fixing effect of the chip, elastic cover plates, suction heads and other parts that cooperate with the chip positioning grooves 31 can also be provided to press the chip tightly to ensure that the chip pins are connected to the conductive film and the chip pads 22 on the PCB copper clad plate 20.

[0044] The conductive film is placed between the PCB copper clad plate 20 and the chip positioning frame 30, and its outer dimensions should be larger than the chip package dimensions to ensure smooth conduction. The thickness of the conductive film can be 0.15 mm.

[0045] When using the fixture 1 for RF testing of microwave devices provided by the embodiment of the utility model, firstly, the fixed base 10, the PCB copper-clad plate 20 and the two RF connectors 40 are well soldered by solder paste, the fixed base 10 is placed on a seismic isolation table or other operating platform, and the fixed base 10 is fixed by a fixture or fastener to ensure that the fixed base 10 will not shake in the horizontal and vertical directions during the test. Then, the test system is built, the transmission and reception of RF signals are realized by a vector network analyzer, the microwave device is powered on and the current is monitored, and the test state is calibrated using a power meter and an electronic calibration component.

[0046] After all the settings are completed, use the RF line to connect the RF connector 40, and connect it to the input port and output port of the calibrated vector network analyzer respectively. Use a wire to connect the powered pad 25 on the PCB copper-clad board 20 to the power supply. After all the connections are correct, place the device to be tested in the chip positioning groove 31 of the chip positioning frame 30 and fix it. Power on the device through the power supply, and the program controls the opening of the gate voltage and the leakage voltage and the search for the static working current. After finding the working current, turn on the RF power switch of the vector network analyzer, and test the corresponding conditions for different indicators. The vector network analyzer sends a radio frequency signal to the coplanar waveguide input terminal 21. Further, the radio frequency signal is sent through the coplanar waveguide output terminal 23 after being processed by the chip, and is transmitted to the receiving port of the vector network analyzer through the radio frequency line. The vector network analyzer processes the received radio frequency signal, evaluates the chip performance through analysis, and after the test is completed, takes out the chip that has been tested, puts in the next one, and reruns the test program.

[0047] It should be noted that since the chip is always accompanied by heat during the power-on test, the conductive film used has good contact with the fixture PCB copper clad plate 20, has the advantages of good heat dissipation and long life. A piece of conductive film can be reused in the fixture for tens of thousands of times. When the service life is reached, it can be seen that the performance indicators of the tested chip are significantly different from before. Therefore, the conductive film should be replaced in time after being damaged due to excessive heat.

[0048] In some possible embodiments, the fixture 1 for radio frequency testing of microwave devices further includes a pressure cover 50, which is detachably disposed above the chip positioning frame 30. The pressure cover 50 and the chip positioning frame 30 or the fixed base 10 can be detachably connected by means of a clamp, a screw, a thread, etc. The pressure cover 50 is used to press the chip of the microwave device downward to ensure that the chip is in close contact with the chip pad 22.

[0049] See also Figure 5 In some possible embodiments, the pressure cap 50 is further provided with an elastic pressure block 51 corresponding to the chip positioning groove 31, and the elastic pressure block 51 is used to press the chip to be tested after the pressure cap 50 is installed. The elastic pressure block 51 can be made of a rubber material with elastic deformation characteristics, or an elastic spring can be provided on the side of the pressure block away from the chip to ensure that the pressure cap 50 has a certain elasticity in contact with the product during the pressure test, so that the product cap will not be damaged by too much pressure.

[0050] See also Figure 5 In some possible embodiments, a positioning pin 52 is further provided on the pressure cover 50 , and the positioning pin 52 can cooperate with the chip positioning frame 30 or the fixed base 10 to ensure that the pressure cover 50 is accurately positioned.

[0051] See also Figure 2 , Figure 3 and Figure 4 In some possible embodiments, the fixing base 10 is provided with a first fixing hole 11 and a second fixing hole 12, the first fixing hole 11 is a through hole, the second fixing hole 12 passes through the upper surface of the fixing base 10, and the second fixing hole 12 is a threaded hole; the chip positioning frame 30 is provided with a third fixing hole 32 corresponding to the second fixing hole 12, and the PCB copper clad plate 20 is provided with a fourth fixing hole 24 corresponding to the second fixing hole 12, and the third fixing hole 32 and the fourth fixing hole 24 are both through holes.

[0052] In this embodiment, the fixed base 10 is provided with a plurality of through first fixing holes 11 for inserting screws to fix the fixed base 10 on a table surface such as a seismic isolation table. The second fixing holes 12 are threaded holes, and a plurality of third fixing holes 32 and fourth fixing holes 24 are provided corresponding to the second fixing holes 12, for connecting and fixing the chip positioning frame 30, the PCB copper clad plate 20 and the fixed base 10 by screws.

[0053] See also Figure 1 In some possible embodiments, a guiding slope is formed on the inner wall of the upper portion of the chip positioning groove 31. In this embodiment, a guiding slope is formed on the inner wall of the upper portion of the chip positioning groove. When placing the chip, the chip can be accurately positioned with the power supply and RF pins on the chip pad 22 through the positioning effect of the guiding slope of the positioning frame and the chip positioning groove 31, and can be well contacted with each other using the conductive adhesive film.

[0054] See also Figure 3 and Figure 4 In some possible embodiments, the PCB copper clad plate is further provided with a plurality of pin insertion holes 221, and the inner wall of the pin insertion hole 221 is provided with a copper material layer. The pin insertion hole 221 is a through hole, and the inner wall surface is provided with a copper material, which can connect the middle pin of the chip with the fixed base 10, ensuring that the chip is well grounded and the core area has good heat dissipation.

[0055] See also Figure 1 and Figure 2 In some possible embodiments, the RF connector 40 is an SMA RF connector 40. In this embodiment, the RF connector 40 is an SMA RF connector 40, which is welded and connected to the coplanar waveguide input terminal 21, the coplanar waveguide output terminal 23 and the fixture base on the PCB copper clad plate 20 by using an SMA RF connector 40 without a connection wall. Since there is no connection wall, the loss of the RF signal at the SMA RF connector 40 is reduced, which helps to obtain more accurate test results.

[0056] In some possible embodiments, the RF connector 40 is connected to the corresponding coplanar waveguide input terminal 21 or coplanar waveguide output terminal 23 by soldering. In this embodiment, the PCB copper clad board 20 and the signal line on the SMA RF connector 40 are connected by soldering with solder paste, which can ensure the stable transmission of the RF signal.

[0057] like Figure 3 As shown, a plurality of grounding holes are densely provided on the PCB copper clad board 20. The grounding holes can reduce the influence of electromagnetic interference of the circuit on the copper clad board on the device test, thereby ensuring the accuracy of the test results.

[0058] It can be understood that the various parts in the above-mentioned embodiments can be freely combined or deleted to form different combination embodiments. The specific contents of each combination embodiment will not be repeated here. After this description, it can be considered that the utility model specification has recorded various combination embodiments and can support different combination embodiments.

[0059] 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 and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fixture for radio frequency testing of microwave devices, characterized in that: include: Fixed base; A PCB copper-clad plate is arranged on the upper surface of the fixed base, and the PCB copper-clad plate has a chip pad, a coplanar waveguide line input end and a coplanar waveguide line output end, and the coplanar waveguide line input end and the coplanar waveguide line output end are arranged on opposite sides of the PCB copper-clad plate, and are electrically connected to the chip pad respectively; A conductive adhesive film is provided on the upper surface of the PCB copper clad plate; A chip positioning frame is provided on the upper surface of the conductive adhesive film, the chip positioning frame is provided with a chip positioning groove which passes through the upper and lower parts, and the chip positioning groove corresponds to the chip pad in the upper and lower parts; and Two radio frequency connectors are arranged on opposite sides of the fixed base, wherein one of the radio frequency connectors is electrically connected to the input end of the coplanar waveguide line, and the other radio frequency connector is electrically connected to the output end of the coplanar waveguide line.

2. The fixture for microwave device radio frequency testing according to claim 1, characterized in that: The fixture for radio frequency testing of microwave devices also includes a pressure cover, which is detachably arranged above the chip positioning frame.

3. The fixture for microwave device radio frequency testing according to claim 2, characterized in that: The pressure cover is also provided with an elastic pressure block corresponding to the chip positioning groove.

4. The fixture for microwave device radio frequency testing according to claim 2, characterized in that: The gland is also provided with a positioning pin.

5. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: The fixing base is provided with a first fixing hole and a second fixing hole, the first fixing hole is a through hole, the second fixing hole at least passes through the upper surface of the fixing base, and the second fixing hole is a threaded hole; the chip positioning frame is provided with a third fixing hole corresponding to the second fixing hole, and the PCB copper clad plate is provided with a fourth fixing hole corresponding to the second fixing hole, and the third fixing hole and the fourth fixing hole are both through holes.

6. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: A nickel-gold layer is provided on the upper surface of the PCB copper-clad plate, and the thickness of the nickel-gold layer is greater than 0.05 μm.

7. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: The PCB copper-clad plate is also provided with a plurality of pin insertion holes, and the inner walls of the pin insertion holes are provided with a copper material layer.

8. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: The radio frequency connector is an SMA radio frequency connector.

9. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: The inner wall of the upper portion of the chip positioning groove is formed with a guiding inclined surface.

10. The fixture for radio frequency testing of microwave devices according to claim 1, characterized in that: The radio frequency connector is connected to the corresponding coplanar waveguide line input end or coplanar waveguide line output end through soldering.

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