PCBA impedance testing fixture
By designing PCBA impedance testing fixtures and utilizing a combination of telescopic probes and shielding plates, the problem of customizing test boards for different types of circuit boards was solved, enabling universal testing of multiple circuit board models and reducing testing costs.
Patent Information
- Application Number
- CN202522669819.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-17
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-12-17
AI Technical Summary
Existing test boards need to be customized for different PCBA circuit board models, resulting in high testing costs and making it impossible to achieve universal testing for multiple circuit board models.
Design a PCBA impedance testing fixture, including a test board, a probe board, and a shield. By setting telescopic probes and multiple sets of pads on the probe board, and using the shield to selectively expose the telescopic probes to connect with test points of different types of circuit boards, universal testing of multiple circuit board models can be achieved.
Impedance testing of different circuit boards can be achieved by changing the shielding plate, which reduces testing costs and improves the versatility and economy of the test board.
Smart Images
Figure CN224946090U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of circuit board processing technology, specifically to a PCBA impedance testing fixture. Background Technology
[0002] During the production of PCBA circuit boards, impedance testing is often required on the completed PCBA circuit boards to verify whether they meet the design requirements.
[0003] When performing impedance testing on PCBA circuit boards, a test board is used. The test board can provide basic operating conditions such as power supply and grounding for the PCBA circuit board. The test board is also electrically connected to the impedance test points of the PCBA circuit board to analyze the impedance of the PCBA circuit board through the electrical signal (usually voltage) at the impedance test points.
[0004] The electrical connection between the existing test board and the PCBA circuit board is achieved by probes fixedly mounted on the test board contacting the pads on the PCBA circuit board. Specifically, the test board has probe positions corresponding to the pads of power, ground, and impedance test points on a certain type and model of PCBA circuit board. During testing, the PCBA circuit board is inserted into the probes on the test board, so that the probes contact the corresponding pads.
[0005] PCBA circuit boards of the same type but different models have the same operating conditions and the same number of impedance test points. The only difference is the position of the power, ground, and impedance test pads on the PCBA circuit board. Since the probe positions on the test board are fixed, it is necessary to customize test boards for different models of PCBA circuit boards in actual testing. The cost of the test boards is relatively high, which increases the testing cost. Utility Model Content
[0006] The purpose of this invention is to provide a PCBA impedance testing fixture.
[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:
[0008] A PCBA impedance testing fixture includes a test board, wherein the test board is provided with multiple sets of first pads, and the multiple sets of first pads are respectively set to test points on multiple types of PCBA circuit boards under test;
[0009] It also includes a probe board fixed on the test board, wherein telescopic probes are provided on the probe board in one-to-one correspondence with the first pad;
[0010] It also includes replaceable shielding plates stacked on the probe plate. Each shielding plate corresponds to a PCBA circuit board under test. Each shielding plate has a through hole for the top of the telescopic probe to be exposed. Each through hole on each shielding plate corresponds to a test point on the corresponding PCBA circuit board under test.
[0011] As a further improvement of this utility model, a first magnetic sheet is embedded in the probe plate, and a second magnetic sheet is provided on the shielding plate for attracting the first magnetic sheet.
[0012] As a further improvement of this utility model, the probe plate is provided with positioning posts around its perimeter.
[0013] As a further improvement of this utility model, it also includes a cover plate, one end of which is connected to a positioning post on one side by a hinge, and the other end of which is snapped to a positioning post on the opposite side.
[0014] As a further improvement of this utility model, the cover plate has a soft pad on the side that mates with the PCBA circuit board to be tested.
[0015] As a further improvement of this utility model, the probe plate and the shielding plate are both made of insulating plastic.
[0016] Compared with the prior art, the technical advantages of this utility model are as follows:
[0017] The test board and probe board of this utility model are equipped with multiple sets of first pads and telescopic probes at the test points on different models of PCBA circuit boards. The telescopic probes used for electrical connection with the PCBA circuit board under test are selected by a shielding plate. Only the shielding plate needs to be replaced (the shielding plate is much cheaper than the test board), and the test board can be used for impedance testing of various models of PCBA circuit boards without replacing the test board. It has good versatility and economy. Attached Figure Description
[0018] Figure 1 This is an exploded structural diagram of a PCBA impedance testing fixture and a PCBA circuit board under test according to a specific embodiment of this utility model.
[0019] Figure 2 This is a schematic diagram of the structure of a PCBA impedance testing fixture when the shield is removed in a specific embodiment of this utility model;
[0020] Figure 3 This is a schematic diagram of the structure of a PCBA impedance testing fixture after installing a shielding plate in a specific embodiment of this utility model;
[0021] Figure 4This is a structural schematic diagram of a PCBA impedance testing fixture in use according to a specific embodiment of this utility model;
[0022] Figure 5 This is a schematic diagram of the cross-sectional structure of the telescopic probe. Detailed Implementation
[0023] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the protection scope of the present invention.
[0024] Please see Figures 1 to 4 A PCBA impedance testing fixture includes a test board 1, on which multiple sets of first pads 11 are provided, and the multiple sets of first pads 11 are respectively set to test points on multiple types of PCBA circuit boards 2 to be tested.
[0025] It also includes a probe plate 3 fixed on the test plate 1, and telescopic probes 31 are provided on the probe plate 3 in one-to-one correspondence with the first pad 11;
[0026] It also includes a replaceable shielding plate 6 stacked on the probe plate 3. The shielding plate 6 is configured one-to-one with the PCBA circuit board 2 under test. The shielding plate 6 is provided with a through hole 61 for the top of the telescopic probe 31 to be exposed. The through hole 61 on each shielding plate 6 is configured to correspond to the test point on the corresponding PCBA circuit board 2 under test.
[0027] The term "multiple PCBA circuit boards under test 2" refers to PCBA circuit boards 2 of the same type but different models. These PCBA circuit boards 2 operate under the same conditions and have the same number of impedance test points; the only difference lies in the location of the power, ground, and impedance test pads on the different models. By simply resolving the connection issues with the test points on the different models of PCBA circuit boards 2, multiple PCBA circuit boards 2 can be tested using a test board 1 with the same circuit structure.
[0028] The test points on the PCBA circuit board 2 under test refer to the pads for power supply, grounding, and impedance test points on the PCBA circuit board 2 under test.
[0029] It should be noted that the circuit structure on the test board 1 is not the focus of this utility model. Existing circuits can be used, such as a power supply circuit electrically connected to the power supply and grounding pads on the PCBA circuit board 2, and a sampling circuit electrically connected to the impedance test point pads on the PCBA circuit board 2.
[0030] The test board 1 may also include an interface for connecting to external impedance analysis equipment (such as a multimeter or oscilloscope).
[0031] Multiple sets of first pads 11 are electrically connected to the circuits on the test board 1. For example, the first pad 11 used to electrically connect to the power and ground pads on the PCBA circuit board 2 under test is electrically connected to the power circuit on the test board 1; the first pad 11 used to electrically connect to the impedance test point on the PCBA circuit board 2 under test is electrically connected to the sampling circuit on the test board 1.
[0032] The present invention aims to solve the connection problem of test points on test board 1 and PCBA circuit boards 2 of the same type but different models, so as to improve the reusability of test board 1.
[0033] The probe plate 3 is fixedly mounted on the test board 1. The bottom end of the telescopic probe 31 contacts the first pad 11. In use, a shielding plate 6 corresponding to the PCBA circuit board 2 under test is selected. The shielding plate 6 has through holes 61 corresponding to the test points on the PCBA circuit board 2 under test, so that the top of the telescopic probe 31 corresponding to the test point on the PCBA circuit board 2 under test extends out through the through holes 61 and makes electrical contact with the test point. The tops of the remaining telescopic probes 31 are pressed down and blocked by the shielding plate 6, and do not contact the PCBA circuit board 2 under test. By replacing the shielding plate 6, electrical connections can be made between the test board 1 and the test points on different models of PCBA circuit boards 2.
[0034] Please see Figure 5 The telescopic probe 31 includes a needle body 311 located in the middle and needle tips 312 located at both ends of the needle body 311. A spring is provided inside the needle body 311 to abut against the needle tips 312 at both ends, so that the needle tips 312 extend out of the needle body 311 when no external force is applied, and retract into the needle body 311 when compressed. The needle body 311 of the telescopic probe 31 is fixedly connected to the probe plate 3.
[0035] Furthermore, a first magnetic sheet 32 is embedded in the probe plate 3, and a second magnetic sheet (not shown) is provided on the shielding plate 6 for attracting the first magnetic sheet 32. The second magnetic sheet is embedded in the bottom of the shielding plate 6, and the second magnetic sheet is aligned with the first magnetic sheet 32. When the shielding plate 6 is stacked on the probe plate 3, the first and second magnetic sheets attract each other, and the shielding plate 6 combines with its own weight to better overcome the spring force in the telescopic probe 31. This allows the shielding plate 6 to press down the top needle 312 of the unused telescopic probe 31, while the top of the telescopic probe 31 that needs to be used is exposed on the top of the shielding plate 6.
[0036] Furthermore, the probe plate 3 is provided with positioning posts 4 around its perimeter. The positioning posts 4 are used to engage with the edge of the shielding plate 6 and play a positioning role when the shielding plate 6 is placed. The through holes 61 on the shielding plate 6 are more easily aligned with the telescopic probe 31.
[0037] Furthermore, it also includes a cover plate 5, one end of which is connected to a positioning post 4 on one side via a hinge, and the other end of which is snap-fitted to a positioning post 4 on the opposite side. The cover plate 5 is used to press against the top surface of the PCBA circuit board 2 during testing to ensure that the test point is in effective contact with the tip of the telescopic probe 31.
[0038] Furthermore, the cover plate 5 has a soft pad 7 on the side that mates with the PCBA circuit board 2 to be tested. The soft pad 7 is preferably an insulating silicone pad. The soft pad 7 allows the cover plate 5 to make flexible contact with the PCBA circuit board 2, preventing the PCBA circuit board 2 from being damaged by the cover plate 5.
[0039] Furthermore, both the probe plate 3 and the shielding plate 6 are made of insulating plastic.
[0040] Compared with the prior art, the technical advantages of this utility model are as follows:
[0041] The present invention provides a test board 1 and probe board 3 with multiple sets of first pads 11 and telescopic probes 31 at the test points on different models of PCBA circuit boards 2. The telescopic probes 31 used for electrical connection with the PCBA circuit board 2 under test are selected by a shielding plate 6. Only the shielding plate 6 needs to be replaced (the shielding plate 6 is much cheaper than the test board 1), and the test board 1 does not need to be replaced. It can be used for impedance testing of various models of PCBA circuit boards 2, and has good versatility and economy.
[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of this utility model.
Claims
1. A PCBA impedance testing fixture, comprising a test board, characterized in that, The test board is provided with multiple sets of first pads, and the multiple sets of first pads are respectively set to test points on multiple types of PCBA circuit boards under test. It also includes a probe board fixed on the test board, wherein telescopic probes are provided on the probe board in one-to-one correspondence with the first pad; It also includes replaceable shielding plates stacked on the probe plate. Each shielding plate corresponds to a PCBA circuit board under test. Each shielding plate has a through hole for the top of the telescopic probe to be exposed. Each through hole on each shielding plate corresponds to a test point on the corresponding PCBA circuit board under test.
2. The PCBA impedance testing fixture according to claim 1, characterized in that, The probe plate is embedded with a first magnetic sheet, and the shielding plate is provided with a second magnetic sheet for attracting the first magnetic sheet.
3. The PCBA impedance testing fixture according to claim 1, characterized in that, The probe plate is equipped with positioning posts around its perimeter.
4. The PCBA impedance testing fixture according to claim 3, characterized in that, It also includes a cover plate, one end of which is connected to a positioning post on one side via a hinge, and the other end of which is snapped to a positioning post on the opposite side.
5. The PCBA impedance testing fixture according to claim 4, characterized in that, The cover plate has a soft pad on the side that mates with the PCBA circuit board to be tested.
6. The PCBA impedance testing fixture according to claim 1, characterized in that, Both the probe plate and the shielding plate are made of insulating plastic.