Kelvin test seat for chip

Abstract

The utility model discloses a Kelvin test seat for a chip, an upper seat is provided with a test groove and an upper guide hole communicated with the test groove, the lower end of a bearing plate is provided with a PCB, the PCB is provided with a lower guide hole communicated with the upper guide hole, and a probe assembly comprises a plurality of probe units composed of a pair of test probes. The test probe is arranged in the upper guide hole and the lower guide hole and comprises a sleeve, an upper probe head, a lower probe head and a spring, the upper probe head comprises a cylinder part, a positioning part and a stabbing part, the positioning part is formed at the upper end of the cylinder part, the upper end face of the positioning part is in a horizontal state, positioning tangent planes are formed on the side walls of the two opposite sides respectively, and the stabbing part is formed on one side of the upper end face of the positioning part; the base is arranged at the lower end of the upper base and located below the bearing plate. The positioning part ensures that the upper needle head moves up and down in a vertical state, rotation is avoided, the side edge position of the upper needle head can be prevented from making contact with the inner wall of the upper guide hole and the like, the upper needle head is prevented from being blocked in the compression or reset process, and the test efficiency and precision are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of chip testing devices, and particularly relates to a Kelvin test socket for chips. Background Art

[0002] When testing a chip, the Kelvin test method has significant advantages compared with other test methods. It can eliminate the influence of wire resistance to make the measurement results reliable and accurate. Secondly, the current lead and voltage lead do not cross, realizing the flexibility and feasibility of measurement in complex circuits. In addition, the stability and repeatability of measurement can be improved by precisely controlling the current and voltage.

[0003] In the prior art, such as a Kelvin test socket for high-current chips with the application number 202221930389.6, its probe holes are improved into straight groove through-hole structures, making the contact between the test probe and the pins of the chip to be tested more accurate and improving the accuracy of chip testing. However, when the needle head and the needle tube (the needle head is arranged in the needle tube through a spring and can move up and down, and a limiting step is formed between the two to prevent the needle head from detaching from the needle tube) move inside the socket body of the test socket, the stepped mating surfaces of the two also move simultaneously. However, the upper end of the needle head has a large and entire upper inclined surface. During the process of piercing the oxide layer on the surface of the chip pin by the upper end of the needle head or during the process of the needle head abutting against and conducting with the PCB board, that is, during the process of the needle head being pressed, the support in the form of the inclined surface will cause uneven force on it, and the needle head may rotate around its axis in the needle tube to a certain extent, making it possible for the steps on the needle head and the steps in the needle tube to cause the needle head to get stuck due to rotation. Moreover, since the side edge formed by the inclined surface has a lower position, when it is pressed down and moves up and down in the test socket hole, the contact between the side edge at the lower position and the inner wall of the hole may also cause a jamming phenomenon. The above will affect the test efficiency and test effect. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a Kelvin test socket for chips. The positioning part of the upper needle head can ensure that the upper needle head moves up and down in a vertical state, avoiding rotation, and only the piercing part located on one side of the upper end of the positioning part makes the upper end of the positioning part have a higher position, which can avoid the contact between the side edge position and the inner walls of the upper guide hole, etc., and avoid the jamming phenomenon of the upper needle head during compression or reset, improving the test efficiency and accuracy.

[0005] To achieve the above purpose, the technical solution adopted by the utility model is: a Kelvin test socket for chips, comprising:

[0006] An upper seat, which is provided with a test slot for placing a chip, and is provided with an upper guide hole that vertically penetrates its body and is communicated with the test slot.

[0007] A carrier plate is fixed to the lower end of the upper seat and has a PCB board at its lower end. The carrier plate is provided with a lower guide hole which vertically penetrates the body and is connected to the upper guide hole. The vertical projection of the lower guide hole is located on the PCB board.

[0008] The probe assembly includes a plurality of probe units consisting of a pair of test probes, wherein the test probes are arranged in an upper guide hole and a lower guide hole, and include a sleeve, an upper needle, a lower needle and a spring. The sides of the upper needle and the lower needle close to each other are respectively limited in the sleeve and abut against the spring respectively, and the ends of the upper needle and the lower needle away from each other are respectively used to abut against the chip and the PCB board. The upper needle includes a column part, a positioning part and a thorn part. The positioning part is formed at the upper end of the column part, and its upper end surface is in a horizontal state, and positioning cut surfaces are respectively formed on the side walls on the opposite sides, and the thorn part is formed on one side of the upper end surface of the positioning part.

[0009] The base is arranged at the lower end of the upper seat and is located below the carrying plate.

[0010] As a further optimization, the upper seat includes a base plate and a limit plate, the base plate is provided with an upper groove, the upper guide hole is formed on the base plate and is connected with the upper groove, the limit plate is provided with a limit groove running through its body, the lower part of the limit plate is arranged in the upper groove and the limit groove forms the test groove.

[0011] As a further optimization, a guiding inclined plate is provided on the limiting plate, so that the chip can smoothly enter the test slot.

[0012] As a further optimization, a clearance groove is provided at the lower end of the guide inclined plate, located beside the limiting groove.

[0013] As a further optimization, the limit plate is locked on the base plate, and a positioning pin is provided between the two to ensure that the positions of the two are accurate when they are installed.

[0014] As a further optimization, the Kelvin test socket also includes a grounding component, which includes a grounding probe and a positioning block. The positioning block is arranged between the upper seat and the carrier plate. The positioning block is provided with a plurality of through holes vertically penetrating its body. The grounding probe is arranged in the through hole for abutting the chip and the PCB board.

[0015] As a further optimization, a first positioning groove is provided on the upper seat, a second positioning groove is provided on the supporting plate, and the positioning block includes an upper positioning block and a lower positioning block, the upper positioning block and the lower positioning block are respectively embedded in the first positioning groove and the second positioning groove, and an upper hole and a lower hole are respectively formed on the two, which are connected to form the through hole.

[0016] As a further optimization, the number of the grounding probes and through holes is four each.

[0017] As a further optimization, the positioning block is made of copper, which can increase electrical conductivity and thermal conductivity.

[0018] As a further optimization, the upper seat, and / or the carrier plate, and / or the base are made of high-temperature resistant engineering plastics; the upper needle tip and / or the lower needle tip are made of palladium alloy, which can improve wear resistance and service life.

[0019] Compared with the prior art, the utility model has the following beneficial effects: The positioning part on the upper needle tip can ensure that the upper needle tip moves up and down in a vertical state without rotation, and the stabbing part located only on one side of the upper end of the positioning part ensures that the upper end of the positioning part has a relatively high position, which can avoid contact with the inner wall of the upper guiding hole, thereby avoiding the jamming phenomenon of the upper needle tip during compression or reset, and improving the test efficiency and accuracy. Description of the Drawings

[0020] Figure 1 is an exploded view of the utility model.

[0021] Figure 2 is a structural diagram of the probe unit of the utility model located in the upper guiding hole and the lower guiding hole.

[0022] Figure 3 is a structural diagram of the upper needle tip of the utility model.

[0023] Figure 4 is a structural diagram of the lower needle tip of the utility model. Detailed Embodiments

[0024] The following are specific embodiments of the utility model in combination with the drawings to further describe the technical solutions of the utility model, but the utility model is not limited to these embodiments.

[0025] Such as Figures 1 to 3As shown in the figure, a Kelvin test socket for a chip includes an upper seat 10, a probe assembly 20, a carrier plate 30 and a base 40. The upper seat 10, the carrier plate 30 and the base 40 are all made of high-temperature resistant engineering plastics. The upper seat 10 is provided with a test slot for placing a chip 100 (such as a QFN48(7x7) chip), and an upper guiding hole 101 vertically penetrating its body and communicating with the test slot. The specific structure of the upper seat 10 includes a substrate 11 and a limiting plate 12. The substrate 11 is provided with an upper slot 110. The upper guiding hole 101 is formed on the substrate 11 and communicates with the upper slot 110. The limiting plate 12 is provided with a limiting slot 120 penetrating its body. The lower part of the limiting plate 12 is arranged in the upper slot 110 and the limiting slot 120 forms the above-mentioned test slot. The carrier plate 30 is fixed to the lower end of the upper seat 10 (substrate 11), and a PCB board is provided at its lower end. The carrier plate 30 is provided with a lower guiding hole 301 vertically penetrating its body and communicating with the upper guiding hole 101. The vertical projection of the lower guiding hole 301 is located on the PCB board. The probe assembly 20 includes a plurality of probe units composed of a pair of test probes 21. The test probes 21 are arranged in the upper guiding hole 101 and the lower guiding hole 301. It includes a sleeve 211, an upper needle head 212, a lower needle head 213 and a spring (not shown). The upper needle head 212 and the lower needle head 213 are both made of palladium alloy. One side of each of them close to the other is respectively limited in the sleeve 211 and abuts against the spring. The ends of them far from each other are respectively used to abut against the chip 100 and the PCB board. The upper needle head 212 includes a columnar part 2121, a positioning part 2122 and a stabbing part 2123. The positioning part 2122 is formed at the upper end of the columnar part 2121. Its upper end face is horizontal, and positioning cut surfaces 212a are respectively formed on the side walls of its opposite sides. The stabbing part 2123 is formed on one side of the upper end face of the positioning part 2122. The base 40 is arranged at the lower end of the upper seat 10 and below the carrier plate 30. The upper seat 10, the carrier plate 30 and the base 40 can be fixedly connected by passing a locking screw through the upper seat 10 and then locking it to the base 40, and the test probe 21 can be movably limited in the upper guiding hole 101 and the lower guiding hole 301; similarly, the limiting plate 12 can also be fixed to the substrate 11 by a locking screw, and a positioning pin is provided between the two to ensure the accuracy of their positions during initial installation.

[0026] In the present utility model, the upper needle 212 on the test probe 21 extends upward out of the upper guiding hole 101, and at least a part of its positioning portion 2122 and the piercing portion 2123 located on the positioning portion 2122 extend into the test groove. The lower needle 213 on the test probe 21 extends downward out of the lower guiding hole 301 and abuts against the PCB board fixed on the carrier plate 30. When testing is required, the chip 100 is placed into the test groove from top to bottom. The pins on the chip 100 abut against the piercing portion 2123. Along with the external downward pressure on the chip 100, the upper needle 212 and the sleeve 211 move downward in the upper guiding hole 101, and the upper needle 212 also moves synchronously within the sleeve 211. Due to the elastic restoring force of the spring, the piercing portion 2123 on the upper needle 212 can pierce the oxide layer on the surface of the chip pin and then achieve electrical signal connection with the PCB board through the compression of the test probe 21. The chip is tested by the testing machine through the test program. During this process, a pair of positioning cut surfaces 212a are provided on the positioning portion 2122, which can cooperate with the vertical surfaces on the upper inner wall of the upper guiding hole 101 to ensure the precise vertical movement of the positioning portion 2122 during the process of being pressed downward or reset. Moreover, the piercing portion 2123 formed only at one side position of the upper end of the positioning portion 2122 can enable the positioning portion 2122 to have a longer extension, avoiding the conventional method of forming a piercing portion by using an inclined cut surface at the upper part of the upper needle, and also avoiding the formation of side edges at a lower position of the upper needle. At least a part of the upper part of the positioning portion 2122 protrudes out of the upper guiding hole during the downward movement (the upper side edge of the positioning portion 2122 does not enter the upper guiding hole 101 to contact the inner wall of the upper guiding hole 101), and the arc-shaped side wall on the positioning portion 2122 can smoothly move within the upper guiding hole 101. Therefore, the upper needle 212 can maintain vertical movement in the compressed state or the reset state, and the probe does not rotate, avoiding the jamming phenomenon after the probe is compressed, and enabling fast and precise testing. In addition, the step 212b formed between the positioning portion 2122 and the columnar portion 2121 can also limit the height of the positioning portion 2122 protruding out of the upper guiding hole 101.

[0027] In the present utility model, the positioning portion 2122 on the upper needle 212 can ensure the vertical up-and-down movement of the upper needle 212 without rotation, and the piercing portion 2123 located only on one side of the upper end of the positioning portion 2122 can ensure that the upper end of the positioning portion 2122 has a relatively high position, avoiding its contact with the inner wall of the upper guiding hole 101, thereby avoiding the jamming phenomenon during the compression or reset process of the upper needle, and improving the efficiency and accuracy of testing.

[0028] The guiding inclined plate 121 is provided on the limiting plate 12, which can conveniently move the chip 100 downward along the guiding inclined plate 121 and, after positioning, make its pins precisely abut against the probe unit.

[0029] A relief groove 121 is provided beside the lower end of the guiding inclined plate 121 in the limiting groove 120, which can avoid interference with the upper part of the upper needle 212.

[0030] Combined Figure 1 、 Figure 3 and Figure 4 As shown, the Kelvin test socket further includes a grounding component 50. The grounding component 50 includes a grounding probe 51 and a positioning block. To make full use of the space, the grounding probe 51 is relatively located within the enclosed space of the probe component 20. It is an ordinary probe that generally does not output frequency and signal and can achieve good conduction for current output. The purpose is to prevent excessive current when testing the chip, lead a certain current out of the chip, prevent the chip from burning out, and has the function of protecting the chip. The grounding probe 51 is stably positioned and installed through the positioning block. The positioning block is made of copper and specifically includes an upper positioning block 52 and a lower positioning block 53. The upper seat 10 (substrate 11) is provided with a first positioning groove 102, and the carrier plate 30 is provided with a second positioning groove 302. The upper positioning block 52 and the lower positioning block 53 are respectively embedded in the first positioning groove 102 and the second positioning groove 302. After the carrier plate 30 is fixed to the upper seat 10 (substrate 11), the positioning block is positioned between the upper seat 10 and the carrier plate 30. Four vertically penetrating holes are respectively provided on the upper positioning block 52 and the lower positioning block 53 through their bodies. After the upper holes and the lower holes are connected, a through hole is formed, and the grounding probe 51 is arranged in the through hole.

[0031] The specific embodiments described in this text are only examples to illustrate the spirit of the present invention. Those skilled in the technical field to which the present invention belongs can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A Kelvin test socket for a chip, characterized in that, include: The upper seat is provided with a test slot for inserting a chip, and is provided with an upper guide hole which vertically penetrates the body and communicates with the test slot. A carrier plate is fixed to the lower end of the upper seat and has a PCB board at its lower end. The carrier plate is provided with a lower guide hole which vertically penetrates the body and is connected to the upper guide hole. The vertical projection of the lower guide hole is located on the PCB board. The probe assembly includes a plurality of probe units consisting of a pair of test probes, wherein the test probes are arranged in an upper guide hole and a lower guide hole, and include a sleeve, an upper needle, a lower needle and a spring. The sides of the upper needle and the lower needle close to each other are respectively limited in the sleeve and abut against the spring respectively, and the ends of the upper needle and the lower needle away from each other are respectively used to abut against the chip and the PCB board. The upper needle includes a column part, a positioning part and a thorn part. The positioning part is formed at the upper end of the column part, and its upper end surface is in a horizontal state, and positioning cut surfaces are respectively formed on the side walls on the opposite sides, and the thorn part is formed on one side of the upper end surface of the positioning part. The base is arranged at the lower end of the upper seat and is located below the carrying plate.

2. The Kelvin test socket for a chip according to claim 1, characterized in that, The upper seat includes a base plate and a limit plate, the base plate is provided with an upper groove, the upper guide hole is formed on the base plate and is connected with the upper groove, the limit plate is provided with a limit groove running through its body, the lower part of the limit plate is arranged in the upper groove and the limit groove forms the test groove.

3. The Kelvin test socket for a chip according to claim 2, characterized in that, The limiting plate is provided with a guide inclined plate.

4. The Kelvin test socket for a chip according to claim 3, characterized in that, The lower end of the guide inclined plate is provided with a clearance groove beside the limiting groove.

5. The Kelvin test socket for a chip according to claim 2, wherein, The limiting plate is locked on the base plate, and a positioning pin is arranged between the two.

6. The Kelvin test socket for a chip according to any one of claims 1 to 4, characterized in that, It also includes a grounding component, which includes a grounding probe and a positioning block. The positioning block is arranged between the upper seat and the supporting plate and is provided with a plurality of through holes vertically penetrating its body. The grounding probe is arranged in the through holes.

7. The Kelvin test socket for a chip according to claim 6, wherein The upper seat is provided with a first positioning groove, the supporting plate is provided with a second positioning groove, the positioning block comprises an upper positioning block and a lower positioning block, the upper positioning block and the lower positioning block are respectively embedded in the first positioning groove and the second positioning groove, and the upper hole and the lower hole are respectively formed on the two to form the through hole after being connected.

8. The Kelvin test socket for a chip according to claim 6, characterized in that, The number of the grounding probes and the number of the through holes are both four.

9. The Kelvin test socket for a chip according to claim 6, characterized in that, The positioning block is made of copper.

10. The Kelvin test socket for a chip according to claim 1, characterized in that, The upper seat, and / or the bearing plate, and / or the base are made of high temperature resistant engineering plastics; the upper needle head and / or the lower needle head are made of palladium alloy.

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