Test fixture for reducing contact resistance using mask plate method

Abstract

This application relates to the technical field of module testing, and in particular to a test fixture for reducing contact resistance using a mask method, comprising a test fixture and a mask. The test fixture has a receiving groove, and multiple probes are mounted at the bottom of the receiving groove. Elastic elements are fitted onto the probes, and the elastic elements are elastically connected to the probes. A cover plate is mounted on the elastic element, and the elastic element drives the cover plate away from the bottom of the receiving groove. The cover plate has test holes and mounting holes. The mask plate is inserted into the mounting holes. The mask plate is made of conductive material. A mounting groove is formed on the side of the mask plate near the probes, and the probes are inserted into the mounting groove. Multiple probes are fixedly connected to the side of the mask plate away from the probes, and the number of probes connected to the mask plate is greater than the number of probes connected. By using multiple probes to abut against the pads, the number of contact points and the contact area between the probes and the pads are increased. This application has the effect of reducing contact resistance and improving production efficiency.

Description

Technical Field

[0001] This application relates to the technical field of module testing, and in particular to a test socket for reducing contact resistance using a mask plate method. Background Technology

[0002] A power supply module is a power supply unit that can be directly mounted on a printed circuit board. Its key feature is its ability to provide power to application-specific integrated circuits (ASICs), digital signal processors (DSPs), microprocessors, memories, programmable gate arrays (PGAs), and other digital or analog loads. These modules are called load power supply systems or point-of-use power supply systems. Due to the numerous advantages of their modular structure, power supply modules are widely used in communication fields such as switching equipment, access equipment, mobile communications, microwave communications, optical transmission, and routers, as well as in automotive electronics, aerospace, and other industries.

[0003] In point-of-load (POT) power supply modules under test (TUPs), the probe contact testing method, where test sockets fix the probes, is commonly used. Currently, commonly available test sockets include the BGA series and QFN series, all employing probe contact testing. However, in probe contact testing, one test point corresponds to one probe. When the power module has many pins, it's difficult to ensure that each probe is on the same plane, leading to uneven contact between the probes and the power module pins.

[0004] Regarding the aforementioned technologies, under both external power and load conditions, the probe tip experiences a significant current. Due to uneven contact between the probe and the power module pins, the contact resistance is higher where the gap between the probe and the power module pins is larger, resulting in a higher current flow at the probe tip. This can lead to discharge at the gap between the probe and the power module pins, oxidizing the probe tip and further increasing the contact resistance. Consequently, the power module's output voltage decreases, causing significant errors in the power module's electrical performance specifications. Furthermore, frequent probe repair and replacement are required during production testing, increasing testing costs and reducing production efficiency. Summary of the Invention

[0005] In order to reduce contact resistance, decrease the frequency of probe maintenance and replacement, and improve production efficiency, this application provides a test fixture for reducing contact resistance using a mask plate method.

[0006] The test fixture for reducing contact resistance using a mask plate method provided in this application adopts the following technical solution:

[0007] A test fixture for reducing contact resistance using a mask plate method, comprising:

[0008] A test stand has a receiving groove, and multiple probes are installed at the bottom of the receiving groove. Each probe is fitted with an elastic element, which is elastically connected to the probe. A cover plate is installed on the elastic element, and the elastic element drives the cover plate away from the bottom of the receiving groove. The cover plate has a test hole and a mounting hole. The test hole is for one probe to pass through, and the mounting hole is for multiple probes in the same functional area to pass through.

[0009] A mask plate is inserted into the mounting hole. The mask plate is made of conductive material. Multiple mounting slots are opened on the side of the mask plate near the probe. Multiple probes are inserted into the multiple mounting slots in a one-to-one correspondence. Multiple probes are fixedly connected to the side of the mask plate away from the probe. The number of probes connected to the mask plate is greater than the number of probes connected.

[0010] By adopting the above technical solution, mounting holes are made on the cover plate near the probes in the same functional area of ​​the test socket to allow the probes in the same functional area to pass through. Then, the mask is inserted into the mounting holes to ensure that the probe, mask, and probe are electrically connected.

[0011] When testing the module under test, the pads of the module under test are brought into contact with multiple probes on the mask, and then the test socket is powered on to complete the test of the module under test.

[0012] This allows multiple probes to contact the pads during the testing of the module under test, increasing the number of contact points and the contact area between the probes and the pads. This reduces the contact resistance between the probes and the module under test during the testing process, thereby improving the stability of the module under test, increasing production efficiency, reducing the possibility of damaging the test socket, and lowering production costs.

[0013] Optionally, the mask plate has a guide slope on the side near the bottom of the receiving groove.

[0014] By adopting the above technical solution, the setting of the guide slope facilitates the insertion of the mask plate into the mounting hole.

[0015] Optionally, multiple mounting holes and multiple mask plates are provided, and the mask plates are inserted into the mounting holes one by one.

[0016] By adopting the above technical solution, mounting holes can be opened in each identical functional area. By using a mask plate and probes, the contact resistance of multiple functional areas can be reduced, making the probes on the test socket less prone to damage.

[0017] Optionally, the probes on each of the mask plates are all on the same plane.

[0018] By adopting the above technical solution, it is easy to process the probes on each mask on the same plane during the manufacturing process. This ensures that when the probes on the mask abut against the pads of the module under test, they are located on the same plane, making the contact between the probes and the pads of the module under test more stable and the contact resistance smaller.

[0019] Optionally, conductive silver paste is applied between the mask and the probe to fix the mask and the probe in place, and the end of the probe and the end of the probe located in the test hole are on the same plane.

[0020] By adopting the above technical solution, the probe and the mask are fixedly connected by conductive silver paste, which makes the probe and the mask have good conductivity and makes the connection of the mask more stable and less prone to shaking.

[0021] Optionally, a locking element is installed on the cover plate to lock the mask plate to the cover plate.

[0022] By adopting the above technical solution, the mask plate and the cover plate are locked together using locking components, reducing the possibility of the mask plate detaching from the mounting hole.

[0023] Optionally, the locking element includes a locking spring, one end of which passes through the cover plate and the other end extends into the mounting hole. A locking groove is provided on the mask plate so that the locking spring can be inserted into the locking groove.

[0024] By adopting the above technical solution, when the mask plate is inserted into the mounting hole, the locking spring is inserted into the locking groove. The locking spring limits the locking groove, thereby reducing the possibility of the mask plate detaching from the mounting hole.

[0025] Optionally, the locking spring is inserted between the two probes, and an abutment rod is fixedly connected between the probes. The abutment rod is located on the side of the locking spring near the bottom of the receiving groove, and the abutment rod is used to abut the locking spring.

[0026] By adopting the above technical solution, when testing the module, the module under test presses the cover plate, causing the cover plate to move towards the bottom of the receiving groove, and the elastic element is compressed. At this time, the probe passes through the test hole and contacts the pad of the module under test.

[0027] As the cover plate moves toward the bottom of the receiving groove, the abutment rod abuts against the locking spring, causing the locking spring to bend. This causes the end of the locking spring extending to the mounting hole to retract into the cover plate, thereby releasing the locking spring from locking the mask plate. This allows the mask plate to be lifted by the probe, thus abutting the probe against the pad of the module under test.

[0028] Once the test is complete, the module under test and the cover plate are slowly moved away from the bottom of the receiving slot by the elastic element. At this time, the mask plate is inserted into the mounting hole again, and the locking spring is reset to lock the mask plate again.

[0029] When the mask needs to be replaced, the cover plate can be pressed directly. When the cover plate moves downward, the abutment rod abuts against the locking spring, causing the locking spring to bend and thus release the locking spring from the mask. This allows the mask to be lifted by the probe and pushed out of the mounting hole, making it easy to remove the mask.

[0030] Optionally, the cover plate has a groove with an arc-shaped cross-section, and the abutment rod has a protrusion that matches the groove so that the protrusion can press the locking spring into the groove.

[0031] By adopting the above technical solution, the use of arc-shaped grooves and protrusions makes the locking spring less prone to bending due to pressure from the protrusions, thus preventing the locking spring from failing and extending its service life.

[0032] Optionally, the side of the mask plate away from the bottom of the receiving groove is located inside the mounting hole, so that the probe is located inside the mounting hole, or the end of the probe away from the mask plate is flush with the surface of the cover plate.

[0033] By adopting the above technical solution, when testing the module under test, the pads of the module under test are made to abut against the cover plate, so as to avoid the module under test being abutted by the probe when it is placed, which would cause the module under test to tilt.

[0034] In summary, this application includes at least one of the following beneficial technical effects:

[0035] By combining the test socket, probes, elastic elements, cover plate, mounting holes, mask plate, and probes, multiple probes abut against the pads of the module under test during the testing process. This increases the number of contact points and the contact area between the probes and the pads, reduces the contact resistance between the probes and the module under test during the testing process, and thus improves the stability of the module under test during the testing process. This achieves the effects of improving production efficiency, reducing the possibility of damaging the test socket, and reducing production costs.

[0036] By applying conductive silver paste between the mask and the probe, the mask and the probe are fixedly connected, and the probe is installed on the same plane as the probes in other areas. This makes the mask installation more stable during installation and testing, and it is not easy for it to shake.

[0037] The mask plate is locked onto the cover plate by the cooperation of the cover plate, the locking spring, and the abutment rod. Pressing the cover plate can release the locking spring from the mask plate, thus making it easy to replace the mask plate. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a test socket for reducing contact resistance using a mask plate method according to Embodiment 1 of this application.

[0039] Figure 2 This is an exploded view of the test fixture in Embodiment 1 of this application.

[0040] Figure 3 This is a schematic diagram of the mask plate in Embodiment 1 of this application.

[0041] Figure 4 This is an exploded view of the probe in Embodiment 1 of this application.

[0042] Figure 5 This is a schematic diagram of the test socket in Embodiment 2 of this application.

[0043] Figure 6 yes Figure 5 Sectional view at point AA.

[0044] Figure 7 yes Figure 6 Enlarged view of point B in the middle.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. Test base; 11. Receiving groove; 12. Limiting rod; 2. Mask plate; 21. Mounting groove; 22. Probe; 23. Guide slope; 24. Locking groove; 3. Probe; 31. Elastic element; 311. Spring; 312. Sliding sleeve; 4. Cover plate; 41. Test hole; 42. Mounting hole; 43. Groove; 5. Cover plate; 51. Pressure plate; 52. Knob; 53. Snap-fit ​​ear; 6. Locking element; 61. Locking spring; 62. Abutment rod; 63. Protrusion. Detailed Implementation

[0047] The following is in conjunction with the appendix Figure 1-7 This application will be described in further detail.

[0048] This application discloses a test fixture for reducing contact resistance using a mask plate method. Example

[0049] Reference Figure 1-3A test fixture for reducing contact resistance using a mask plate method includes a test fixture 1 and a mask plate 2. The test fixture 1 has a receiving groove 11, and multiple probes 3 are mounted at the bottom of the receiving groove 11. An elastic element 31 is fitted onto each probe 3, and the elastic element 31 is elastically connected to the probe 3. A cover plate 4 is mounted on the elastic element 31, and the elastic element 31 drives the cover plate 4 away from the bottom of the receiving groove 11. The cover plate 4 has a test hole 41 and a mounting hole 42. The test hole 41 allows one probe 3 to pass through, and the mounting hole 42 allows multiple probes 3 of the same functional area to pass through. The mask plate 2 is inserted into the mounting hole 42. The mask plate 2 is made of conductive material. A mounting groove 21 is formed on the side of the mask plate 2 closest to the probe 3, and the probe 3 is inserted into the mounting groove 21. Multiple probes 22 are fixedly connected to the side of the mask plate 2 away from the probe 3, and the number of probes 22 connected to the mask plate 2 is greater than the number of probes 3 connected.

[0050] During the testing of the module under test, multiple probes 22 are used to contact the pads of the module under test, increasing the number of contact points and the contact area between the probes 22 and the pads of the module under test. This reduces the contact resistance between the probes 3 and the module under test during the test, thereby improving the stability of the module under test, increasing production efficiency, reducing the possibility of damaging the test socket, and reducing production costs.

[0051] In this embodiment, a cover plate 5 is rotatably connected to the test base 1. A pressure plate 51 is inserted into the cover plate 5. A limit block is connected to the part of the pressure plate 51 that passes through the cover plate 5 so that the pressure plate 51 slides only in a direction perpendicular to the cover plate 5. A knob 52 is threadedly connected to the end of the cover plate 5 away from the test base 1. The knob 52 is engaged on the side of the cover plate 5 away from the test base 1 so that the knob 52 rotates only on the cover plate 5.

[0052] A limiting rod 12 is fixedly connected to one side of the test seat 1, and a snap-fit ​​ear 53 is rotatably connected to the cover plate 5. By snapping the snap-fit ​​ear 53 onto the limiting rod 12, the test seat 1 and the cover plate 5 are closed.

[0053] Reference Figure 2 and 4 The elastic element 31 includes a spring 311 and a sliding sleeve 312. The sliding sleeve 312 is sleeved on the probe 3. One end of the spring 311 is fixedly connected to the probe 3, and the other end is fixedly connected to the sliding sleeve 312. The spring 311 drives the sliding sleeve 312 to move away from the bottom of the receiving groove 11. The cover plate 4 overlaps the sliding sleeve 312, so that when the spring 311 drives the sliding sleeve 312 to move away from the bottom of the receiving groove 11, it simultaneously drives the cover plate 4 to move away from the bottom of the receiving groove 11.

[0054] When testing the module under test, first open the cover plate 5, place the module under test on the cover plate 4, close the cover plate 5 and make the locking lug 53 lock onto the limiting rod 12, rotate the knob 52 to make the pressure plate 51 press the module under test, the module under test presses the cover plate 4, the cover plate 4 compresses the spring 311 until the probe 3 located in the test hole 41 and the probe 22 on the mask plate 2 abut against the pad of the module under test, and then start testing the module under test.

[0055] The mask plate 2 can be made of silver or copper. To save costs, copper is selected as the material for the mask plate 2 in this embodiment. The size of the mask plate 2 is perfectly matched with the size of the mounting hole 42 so that the sidewall of the mask plate 2 is pressed against the inner sidewall of the mounting hole 42, making the mask plate 2 more stable when inserted into the mounting hole 42.

[0056] In this embodiment, there are two probes 3 in the same functional area. The same functional area indicates that the test socket contains similar circuit elements, signal transmission paths, or other related functions, thus allowing for similar testing steps or methods. Mounting holes 42 are formed in the areas of two adjacent probes 3 located in the same functional area on the cover plate 4, and the ends of the probes 3 in the same functional area are machined into a columnar shape. The columnar probes 3 facilitate insertion into the mounting slots 21 of the mask plate 2. Five probes 22 are fixedly connected to the cover plate 4. The position and shape of the probes 22 can be set according to the pads of the module under test in the corresponding area.

[0057] Since the pads of the module under test are usually larger than the actual contact area of ​​the probe 3, in this embodiment, five probes 22 are used to contact the pads of the module under test, so that the five probes 22 can contact the edge of the pads of the module under test. Compared with the two probes 3 contacting the pads of the module under test, this greatly increases the contact points and contact area with the pads of the module under test, thereby reducing the contact resistance.

[0058] Because probe 3 is small and the probes 3 on test socket 1 are relatively dense, existing processes are difficult to improve the area where a single probe 3 is located. In order to facilitate increasing the number of contact points and contact area between probe 3 and the pads of the module under test, thereby reducing the contact resistance between probe 3 and the module under test (for specific formulas, please refer to Yang Jinghua—A Brief Discussion on the Calculation Method of Contact Resistance and Electrodynamic Repulsion of Isolation Contacts), this application integrates the probe 3 areas of the same functional area of ​​the module under test, and uses laser to divide the corresponding areas of the cover plate 4 and probe 3, increasing the operable area. This facilitates increasing the number of contact points and contact area between the pads and probe 22 in the same functional area of ​​the module under test, thereby reducing the contact resistance between probe 3 and the module under test.

[0059] Reference Figure 2 and Figure 3In an optional embodiment, a guide slope 23 is provided on the side of the mask plate 2 near the bottom of the receiving groove 11. The guide slope 23 reduces the area of ​​the end face of the mask plate 2 near the end of the receiving groove 11, making it easier to insert the mask plate 2 into the mounting hole 42.

[0060] Both mounting holes 42 and mask plates 2 are provided with multiple mounting holes 42. In this embodiment, both mounting holes 42 and mask plates 2 are provided with three mounting holes 42. The number of mounting holes 42 can be divided according to the functional area of ​​the module under test. Mounting holes 42 can be opened on the cover plates 4 around the probes 3 that test the same functional area. The mask plates 2 are inserted into the mounting holes 42 one by one.

[0061] Mounting holes 42 can be opened on the cover plate 4 corresponding to each identical functional area. The contact resistance of each functional area can be reduced by using the mask plate 2 and the probe 22, making the probes 3 of multiple functional areas on the test base 1 less prone to damage.

[0062] Because there are a large number of probes 3, it is difficult to ensure that all probes 3 on the test socket 1 are located on the same plane during the manufacturing process. However, each mask plate 2 has five probes 22, making it easier to manufacture the probes 22 on the mask plate 2 so that they are located on the same plane. When the probes 22 on the same plane come into contact with the pads of the module under test, there is less chance of gaps, making the testing of the module under test more stable.

[0063] The probes 22 on each mask 2 are all on the same plane, which ensures that the probes 22 on each mask 2 can be located on the same plane when they abut against the pads of the module. This makes the contact between the probes 22 of each functional area and the pads of the module more stable, and thus reduces the contact resistance.

[0064] To prevent the mask 2 from falling off during use after it is installed on the probe 3, conductive silver paste is applied between the mask 2 and the probe 3. The conductive silver paste is used to fix the mask 2 and the probe 3 to the mask 2, so that the probe 3 and the mask 2 have good conductivity. At the same time, it makes the connection of the mask 2 more stable and less prone to shaking.

[0065] The end of the probe 22 on the mask plate 2 and the end of the probe 3 located in the test hole 41 are on the same plane, so that when the probe 22 on the mask plate 2 contacts the pad on the module under test, the end of the probe 3 can also contact the pad, thereby avoiding poor contact between the probe 3 or the probe 22 and the pad on the module under test.

[0066] The implementation principle of Embodiment 1 of this application is as follows: the same functional area of ​​the module to be tested is determined, then the corresponding mounting hole 42 is opened on the cover plate 4, and the end of the probe 3 located in the mounting hole 42 area is replaced with a column, and conductive silver paste is applied to the end of the probe 3. Then the mounting groove 21 on the mask plate 2 is aligned with the probe 3, and the probe 3 is inserted into the mounting groove 21, while the end of the probe 22 is located on the same plane as the ends of the probe 3 in other areas.

[0067] When testing the module under test, the module under test is installed on the cover plate 4, then the cover plate 5 is placed on top, and the knob 52 is rotated so that the pressure plate 51 presses the module under test against the probe 3 and the probe 22 presses against the pads of the module under test, and then the module under test is tested.

[0068] During the test, multiple probes 22 are used to contact the pads, increasing the number of contact points and the contact area between the probes 22 and the pads. This reduces the contact resistance between the probes 3 and the module under test during the test, thereby improving the stability of the module test, increasing production efficiency, reducing the possibility of damaging the test socket, and reducing production costs. Example

[0069] During the testing of the module under test, the tip of probe 22 is most prone to discharge, which can cause oxidation. Once the tip of probe 22 is oxidized, the entire mask 2 must be replaced. However, in Embodiment 1, the mask 2 and probe 3 are fixedly connected by conductive silver paste, making it inconvenient to replace the mask 2 in Embodiment 1.

[0070] Reference Figure 5-7 The difference between Example 2 and Example 1 is that in Example 2, a locking member 6 is used to lock the mask plate 2 and the cover plate 4 to prevent the mask plate 2 from detaching from the cover plate 4. At the same time, it is convenient to use the locking member 6 to unlock the cover plate 4 and replace the cover plate 4.

[0071] The locking element 6 includes a locking spring 61 and an abutment rod 62. One end of the locking spring 61 passes through the cover plate 4 and the other end extends into the mounting hole 42. The end located inside the cover plate 4 is fixedly connected to the cover plate 4. The mask plate 2 has a locking groove 24. When the mask plate 2 is inserted into the mounting hole 42, the locking spring 61 is inserted into the locking groove 24. The locking spring 61 limits the locking groove 24, thereby reducing the possibility of the mask plate 2 coming out of the mounting hole 42.

[0072] Furthermore, since the mask plate 2 has a guide slope 23 on the side near the bottom of the receiving groove 11, the guide slope 23 not only facilitates the insertion of the mask plate 2 into the mounting hole 42, but also allows the guide slope 23 and the locking groove 24 to be positioned on the same side of the mask plate 2. Thus, when the mask plate 2 is installed in the mounting hole 42, the guide slope 23 first abuts against the locking spring 61, causing the locking spring 61 to gradually retract into the cover plate 4 under the gradual compression of the guide slope 23. This facilitates the continued movement of the mask plate 2 toward the interior of the mounting hole 42 until the locking groove 24 moves to the corresponding position with the locking spring 61, at which point the locking spring 61 pops out, locking the mask plate 2 onto the cover plate 4.

[0073] When the locking spring 61 locks the mask plate 2 onto the cover plate 4, the side of the mask plate 2 away from the bottom of the receiving groove 11 is located inside the mounting hole 42, and the probe 22 is located inside the mounting hole 42, or the end of the probe 22 away from the mask plate 2 is flush with the surface of the cover plate 4. In this embodiment, it is preferable that the end of the probe 22 away from the mask plate 2 is flush with the surface of the cover plate 4. Since the module under test is placed on the cover plate 4, in order to avoid the module under test directly abutting against the probe 22 when the pressure plate 51 is pressing the module under test, which would cause the end of the probe 22 to be damaged by force, the end of the probe 22 is completely accommodated in the mounting hole 42. This avoids the module under test being abutted by the probe 22 when the module under test is placed, which would cause the module under test to be uneven and cause the end of the probe 22 to be damaged by force.

[0074] In this embodiment, the locking spring 61 is inserted between two adjacent probes 3, and the abutment rod 62 is fixedly connected to the probe 3 or the test seat 1. The abutment rod 62 is located on the side of the locking spring 61 near the bottom of the receiving groove 11. When the cover plate 4 moves toward the bottom of the receiving groove 11, the abutment rod 62 can abut against the locking spring 61.

[0075] The abutting rod 62 abuts against the locking spring 61, causing the locking spring 61 to deform, thereby retracting the part extending into the mounting hole 42 into the cover plate 4, and thus causing the locking spring 61 to disengage from the locking groove 24, releasing the locking spring 61 from the mask plate 2.

[0076] In an optional embodiment, a groove 43 is provided in the cover plate 4. The cross-section of the groove 43 is arc-shaped. The arc-shaped groove 43 facilitates better transition when the locking spring 61 deforms, so as to facilitate the reset of the locking spring 61. A protrusion 63 is fixedly connected to the abutment rod 62. The protrusion 63 matches the groove 43 so that the protrusion 63 can press the locking spring 61 into the groove 43.

[0077] By utilizing the interlocking arc-shaped groove 43 and protrusion 63, the locking spring 61 is less prone to significant bending when repeatedly compressed, thus preventing it from losing its shape and failing. The compression from the arc-shaped groove 43 and protrusion 63 ensures good springback even when the locking spring 61 is repeatedly bent, thereby extending its service life.

[0078] The implementation principle of Example 2 is as follows: When the mask plate 2 needs to be replaced, the cover plate 4 is manually pressed, causing the cover plate 4 to move towards the bottom of the receiving groove 11. At this time, the abutment rod 62 abuts against the locking spring 61, causing the locking spring 61 to bend. The end of the locking spring 61 extending to the mounting hole 42 retracts into the cover plate 4, and the locking spring 61 disengages from the locking groove 24, releasing the lock on the mask plate 2. At this time, the probe 3 is inserted from the mounting groove 21 into the mask plate 2 and abuts against the mask plate 2. The mask plate 2 is disengaged from the mounting hole 42 due to the abutment of the probe 3. The cover plate 4 is released, and the cover plate 4 is quickly reset by the elasticity of the elastic element 31. At this time, the mounting groove 21 cannot enter the mounting hole 42 due to the friction between it and the inner wall of the mounting hole 42, causing the probe 3 to disengage from the mounting groove 21. The mask plate 2 falls onto the cover plate 4, thus completing the disassembly of the mask plate 2.

[0079] Align the mask 2 to be replaced with the mounting hole 42, press the mask 2 until the locking spring 61 is inserted into the locking groove 24, and the installation of the mask 2 is completed.

[0080] When testing the module under test (DUT), rotating knob 52 causes pressure plate 51 to press and move the DUT, bringing the DUT's pads into contact with probe 3 or probe 22. Simultaneously, the DUT presses the cover plate 4 towards the bottom of the receiving groove 11. As the cover plate 4 moves towards the bottom of the receiving groove 11, the abutment rod 62 abuts against the locking spring 61, causing the locking spring 61 to bend. This causes the end of the locking spring 61 extending into the mounting hole 42 to retract into the cover plate 4, thereby releasing the locking spring 61 from locking the mask plate 2. At this point, the mask plate 2 is lifted by probe 3, causing probe 22 on the mask plate 2 to abut against the DUT's pads. During testing, the mask plate 2 can detach from the cover plate 4, allowing for better contact between probe 22 and the DUT's pads.

[0081] After the test is completed, the knob 52 is rotated in the opposite direction, causing the pressure plate 51 to gradually move away from the bottom of the receiving groove 11. At this time, the module under test and the cover plate 4 are driven by the elastic element 31 to slowly move away from the bottom of the receiving groove 11. The mask plate 2 is squeezed by the module under test and is inserted into the mounting hole 42 again until the locking spring 61 resets and locks the mask plate 2 again. Therefore, after the module under test is taken out, the mask plate 2 is still locked in the mounting hole 42, which facilitates continuous testing of the module under test.

[0082] In this embodiment, the locking element 6 not only facilitates the disassembly and replacement of the mask plate 2, but also allows the mask plate 2 to detach from the mounting hole 42 and abut against the pads of the module under test when the module under test is being tested. After the test is completed, the mask plate 2 can be installed back into the mounting hole 42, enabling the test fixture to perform continuous testing and greatly improving the testing efficiency.

[0083] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A test fixture for reducing contact resistance using a mask plate method, characterized in that, include: Test base (1), the test base (1) has a receiving groove (11) and a plurality of probes (3) are installed at the bottom of the receiving groove (11). An elastic element (31) is sleeved on the probe (3) and the elastic element (31) is elastically connected to the probe (3). A cover plate (4) is installed on the elastic element (31) and the elastic element (31) drives the cover plate (4) away from the bottom of the receiving groove (11). The cover plate (4) has a test hole (41) and a mounting hole (42). The test hole (41) is used for one probe (3) to pass through, and the mounting hole (42) is used for multiple probes (3) in the same functional area to pass through. A mask plate (2) is inserted into the mounting hole (42). The mask plate (2) is made of conductive material. A mounting groove (21) is provided on the side of the mask plate (2) near the probe (3). The probe (3) is inserted into the mounting groove (21). Multiple probes (22) are fixedly connected to the side of the mask plate (2) away from the probe (3). The number of probes (22) connected to the mask plate (2) is greater than the number of probes (3) connected.

2. The test fixture for reducing contact resistance using a mask plate method according to claim 1, characterized in that: The mask plate (2) has a guide slope (23) on the side near the bottom of the receiving groove (11).

3. A test fixture for reducing contact resistance using a mask plate method according to claim 1, characterized in that: Multiple mounting holes (42) and multiple mask plates (2) are provided, and the mask plates (2) are inserted into the mounting holes (42) one by one.

4. A test fixture for reducing contact resistance using a mask plate method according to claim 3, characterized in that: The probes (22) on each of the mask plates (2) are on the same plane.

5. A test fixture for reducing contact resistance using a mask plate method according to any one of claims 1-4, characterized in that: Conductive silver paste is applied between the mask plate (2) and the probe (3) to fix the mask plate (2) and the probe (3) in place. The end of the probe (22) and the end of the probe (3) located in the test hole (41) are on the same plane.

6. A test fixture for reducing contact resistance using a mask plate method according to any one of claims 1-4, characterized in that: A locking element (6) is installed on the cover plate (4), which is used to lock the mask plate (2) to the cover plate (4).

7. A test fixture for reducing contact resistance using a mask plate method according to claim 6, characterized in that: The locking element (6) includes a locking spring (61), one end of which passes through the cover plate (4) and the other end extends into the mounting hole (42). A locking groove (24) is provided on the mask plate (2) so that the locking spring (61) can be inserted into the locking groove (24).

8. A test fixture for reducing contact resistance using a mask plate method according to claim 7, characterized in that: The locking spring (61) is inserted between the two probes (3), and an abutment rod (62) is fixedly connected between the probes (3). The abutment rod (62) is located on the side of the locking spring (61) near the bottom of the receiving groove (11), and the abutment rod (62) is used to abut the locking spring (61).

9. A test fixture for reducing contact resistance using a mask plate method according to claim 8, characterized in that: The cover plate (4) has a groove (43) with a circular arc cross section. The abutment rod (62) is provided with a protrusion (63) that matches the groove (43) so that the protrusion (63) can press the locking spring (61) into the groove (43).

10. A test fixture for reducing contact resistance using a mask plate method according to claim 6, characterized in that: The side of the mask plate (2) away from the bottom of the receiving groove (11) is located in the mounting hole (42) so that the probe (22) is located in the mounting hole (42), or the end of the probe (22) away from the mask plate (2) is flush with the surface of the cover plate (4).

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