ESD (Electro-Static Discharge) test fixture and method
By designing an ESD test fixture including a movable bracket and a support device, the problem of poor test accuracy and consistency in existing ESD testing methods is solved, and more efficient and accurate test results are achieved.
Patent Information
- Application Number
- CN202411728746.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-03-07
AI Technical Summary
The existing ESD testing methods have problems with poor test accuracy and consistency, which leads to high uncertainty in the test results.
An ESD test fixture is provided, including a movable bracket and a support device, and the test point is aligned and contacted with the electrostatic gun head by adjusting the fixture to improve the accuracy and consistency of the test.
Through the use of ESD test fixtures, the speed and efficiency of test point alignment are significantly improved, and the accuracy and consistency of test results are improved.
Smart Images
Figure CN119574924A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of ESD testing, and in particular to an ESD testing fixture and method. Background Art
[0002] ESD (Electrostatic discharge) is the most common electromagnetic interference, which can affect the functions of various electronic products and even damage them in serious cases. Therefore, ESD anti-interference ability has become an important indicator for measuring electronic products. As the core component of electronic products, chips have increasingly higher requirements for electrostatic protection.
[0003] ESD test is one of the EMC (Electron Magnetic Compatibility) test items. Usually, an ESD generator is used to simulate the electrostatic discharge phenomenon in reality and perform ESD test on electronic products. The conventional test method is to use a handheld electrostatic gun to make the gun tip (discharge electrode) of the electrostatic gun contact the product to be tested, and then apply electrostatic discharge. When performing chip ESD testing, electrostatic interference must be applied to each pin of the chip. Therefore, it is necessary to hold the electrostatic gun and make the gun tip contact the test points of each pin of the chip in turn. The whole operation is time-consuming and laborious. In addition, since manual operation is not stable, there will be certain differences in the contact position, angle, and pressure between the gun tip and the test point each time contact occurs. Therefore, the conventional ESD test method still has the problem of poor test accuracy and consistency, resulting in high uncertainty in the test results. Summary of the invention
[0004] The embodiments of the present application provide an ESD test fixture and method to facilitate accurate positioning and effective contact between the electrostatic gun tip and the test point, and to achieve rapid switching of the test point, thereby improving the accuracy and consistency of the ESD test and improving the test efficiency.
[0005] On the one hand, an embodiment of the present application provides an ESD test fixture, comprising: a movable bracket, and a supporting device arranged on the movable bracket;
[0006] The supporting device is used to place the device under test, and the device under test includes one or more test points;
[0007] The movable bracket is used to drive the device under test to shift in the horizontal direction through the supporting device so that the current test point is aligned with the electrostatic gun head, and then drive the device under test to shift in the vertical direction so that the current test point is in contact with or separated from the electrostatic gun head.
[0008] Optionally, the device under test includes: a PCB board, and one or more chips under test arranged on the PCB board;
[0009] The supporting device comprises: at least three supporting columns, which are used for fixing and supporting the PCB board.
[0010] Optionally, at least three positioning holes are provided on the PCB board;
[0011] The support column comprises an upper column and a lower column, the diameter of the upper column is smaller than the diameter of the lower column and is adapted to the diameter of the positioning hole;
[0012] The lower column is connected and fixed to the movable bracket; the upper column passes through the positioning hole to support and fix the PCB board.
[0013] Optionally, the movable bracket includes: a sliding device, and an elastic device arranged on the sliding device;
[0014] The elastic device is used to fix the supporting device and drive the device to be tested to shift in the vertical direction so that the test point contacts or separates from the electrostatic gun head;
[0015] The sliding device is used to drive the device to be tested to shift in the horizontal direction so that the test point is aligned with the electrostatic gun head.
[0016] Optionally, the sliding device comprises: a base, a foot pad, and a lower clamping block;
[0017] The foot pad is arranged on the lower bottom surface of the base;
[0018] The lower clamping block is arranged on the upper surface of the base.
[0019] Optionally, the surface of the foot pad is an arc-shaped structure.
[0020] Optionally, the foot pad and the base are an integral structure.
[0021] Optionally, the elastic device comprises: a sliding column, a spring, a top seat, a column cap, and an upper clamping block;
[0022] The sliding column is vertically mounted on the base and is used to fix and support the top seat;
[0023] The top seat is provided with a through hole adapted to the sliding column, and the top seat is sleeved on the sliding column through the through hole;
[0024] The spring is sleeved below the top seat on the sliding column;
[0025] The column cap is sleeved on the top of the top seat on the sliding column and can slide up and down along the sliding column to provide a vertical movement travel space for the top seat and limit the upward movement space of the top seat;
[0026] The upper clamping block is arranged on the lower surface of the top seat and corresponds to the lower clamping block, and is used to limit the maximum displacement in the vertical direction and prevent the top seat from colliding with the base.
[0027] Optionally, the lower clamping block and the upper clamping block are made of soft material.
[0028] Optionally, the fixture further includes: a pressure sensing device for determining the pressure of the electrostatic gun tip on the test point to ensure reliable contact between the electrostatic gun tip and the test point and avoid damage to the electrostatic gun tip.
[0029] Optionally, the pressure sensing device comprises: a control panel, and a pressure sensor, a control unit, and an information indicating unit arranged on the control panel; the control panel is arranged on the elastic device;
[0030] The pressure sensor is used to sense the downward pressure of the electrostatic gun tip and convert the pressure into an electrical signal and output it to the control unit;
[0031] The control unit is used to output a control signal to the information indication unit according to the electrical signal;
[0032] The information indicating unit is used to indicate pressure information according to the control signal.
[0033] Optionally, the information indicating unit is a dual-color LED lamp, and the control signal is a voltage signal;
[0034] When the voltage signal is less than a first set value, the bicolor LED lamp generates a first color light;
[0035] When the voltage signal is greater than a second set value, the dual-color LED lamp generates a second color light.
[0036] Optionally, the fixture further comprises:
[0037] An optical magnifying device, used to magnify the area of the test point;
[0038] The optical magnifying device comprises: a fixed bracket and a magnifying glass; the fixed bracket is installed on the elastic device, and the magnifying glass is installed on the fixed bracket.
[0039] Optionally, the fixing bracket comprises: a fixing clamp, a vertical arm and a retractable and rotatable horizontal arm;
[0040] The vertical arm is mounted on the elastic device through a fixing clip, and is used to connect and fix the horizontal arm, and provide a displacement space for the horizontal arm in the vertical direction;
[0041] One end of the horizontal arm is vertically connected to the top of the vertical arm, and the other end is connected to the magnifying glass, and provides a displacement space for the magnifying glass in the horizontal direction;
[0042] The horizontal arm is provided with an adjusting button for adjusting the state of the horizontal arm, so as to adjust the length and rotation angle of the horizontal arm and the rotation angle of the magnifying glass, or to fix the horizontal arm and the magnifying glass.
[0043] On the other hand, an embodiment of the present application further provides an ESD testing method, the method comprising:
[0044] Placing a device under test on an ESD test fixture, wherein the device under test includes one or more test points;
[0045] Adjust the position of the electrostatic gun so that the head of the electrostatic gun is facing downward and suspended in the air close to the device to be tested;
[0046] Determine the current test point, and make the current test point contact with the electrostatic gun head by adjusting the ESD test fixture; the adjusting of the ESD test fixture comprises: firstly controlling the ESD test fixture to shift in the horizontal direction so that the current test point on the device under test is aligned with the electrostatic gun head; then controlling the ESD test fixture to shift in the vertical direction to drive the device under test to rise so that the current test point contacts with the electrostatic gun head;
[0047] After the adjustment is completed, the electrostatic gun is started to discharge and the test of the current test point is completed.
[0048] Optionally, the method further comprises:
[0049] During the adjustment of the ESD test fixture, the pressure of the electrostatic gun tip on the current test point is obtained in real time;
[0050] When the pressure is 0 or the pressure is greater than the set value, the ESD test fixture is moved away, and the process returns to the step of adjusting the position of the electrostatic gun.
[0051] Optionally, the method further comprises:
[0052] During the adjustment of the ESD test fixture, the current test point area is magnified and observed;
[0053] If the electrostatic gun tip is not aligned with the current test point, readjust it.
[0054] The ESD test fixture and method provided in the embodiment of the present application can place the device under test on the ESD test fixture when performing an ESD test on the device under test, and the current test point can be easily brought into contact with the electrostatic gun tip by adjusting the ESD test fixture, thereby improving the speed and efficiency of test point alignment. Moreover, in the process of adjusting the ESD test fixture, coarse adjustment and fixation are first performed, and then fine adjustment and control are performed, thereby improving efficiency and accuracy.
[0055] Furthermore, a sliding device and an elastic device are respectively provided on the ESD, so that the coarse adjustment and fine adjustment processes can be conveniently realized.
[0056] Furthermore, by arranging a pressure sensing device on the sliding device, the pressure of the electrostatic gun tip on the test point can be sensed in real time when the ESD test fixture drives the device to be tested to shift in the vertical direction, thereby ensuring the reliability of the contact between the test point and the electrostatic gun tip. At the same time, it also protects the electrostatic gun tip and prevents it from being damaged by excessive pressure.
[0057] Furthermore, by providing an optical magnifying device, the test point area can be magnified and observed, thereby better ensuring the reliability of the alignment between the test point and the electrostatic gun tip. BRIEF DESCRIPTION OF THE DRAWINGS
[0058] The accompanying drawings are used to provide a clearer understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation to the present application. In the accompanying drawings:
[0059] Figure 1 This is a structural schematic diagram of an ESD test fixture provided in an embodiment of the present application;
[0060] Figure 2 It is a structural schematic diagram of a supporting device in an ESD test fixture provided in an embodiment of the present application;
[0061] Figure 3 This is a structural schematic diagram of a movable bracket in an ESD test fixture provided in an embodiment of the present application;
[0062] Figure 4 This is a front view of a specific structure of the ESD test fixture provided in an embodiment of the present application;
[0063] Figure 5 yes Figure 4 A top view of the ESD test fixture shown;
[0064] Figure 6 It is a structural schematic diagram of a pressure sensing device in an ESD test fixture provided in an embodiment of the present application;
[0065] Figure 7This is a structural schematic diagram of an optical amplification device in an ESD test fixture provided in an embodiment of the present application;
[0066] Figure 8 is a flow chart of the ESD testing method provided in the embodiment of the present application;
[0067] Fig. 9 This is a schematic diagram of using the ESD test fixture provided in an embodiment of the present application to perform horizontal displacement on the device under test;
[0068] Fig.10 This is a schematic diagram of using the ESD test fixture provided in an embodiment of the present application to perform vertical displacement on a device under test.
[0069] Reference numerals:
[0070] 100 devices under test; 101 test points; 301 positioning holes; 1201 through holes;
[0071] 10 movable bracket; 11 sliding device; 12 elastic device;
[0072] 111 base; 112 foot pad; 113 lower clamping block;
[0073] 121 top seat; 122 sliding column; 123 upper clamping block; 124 spring; 125 column cap; 126 flange structure;
[0074] 20 supporting device; 21 lower column; 22 upper column;
[0075] 30 pressure sensing device; 31 control panel; 32 control unit; 33 pressure sensor; 34 information indication unit;
[0076] 40 optical magnifying device; 41 fixing clamp; 42 vertical arm; 43 horizontal arm; 44 magnifying glass;
[0077] 45 adjustment knobs;
[0078] 200 electrostatic gun; 201 electrostatic gun tip. DETAILED DESCRIPTION
[0079] In order to make the above-mentioned purposes, features and beneficial effects of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0080] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.
[0081] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0082] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.
[0083] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0084] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.
[0085] In order to solve the problem of poor accuracy and consistency of test results caused by manual operation when performing chip ESD testing in the prior art, an embodiment of the present application provides an ESD test fixture and method. The ESD test fixture can assist in quickly completing the alignment and reliable contact between the test point and the electrostatic gun tip, thereby improving the test efficiency and the accuracy of the test results.
[0086] like Figure 1 , which is a schematic diagram of the structure of an ESD test fixture provided in an embodiment of the present application.
[0087] The ESD test fixture comprises: a movable bracket 10 and a supporting device 20 arranged on the movable bracket.
[0088] The supporting device 20 is used to place the device under test 100, and the device under test 100 includes one or more test points;
[0089] The movable bracket 10 is used to drive the device under test 100 to shift in the horizontal direction through the supporting device 20 so that the current test point is aligned with the electrostatic gun head, and then drive the device under test 100 to shift in the vertical direction so that the current test point is in contact with or separated from the electrostatic gun head.
[0090] It should be noted that during the test, the electrostatic gun can be fixed on an adjustable bracket and brought close to the test point, with the electrostatic gun head facing downward and suspended close to the device under test 100. Then the movable bracket 10 is adjusted to drive the device under test 100 on the support device 20 to shift horizontally first, align the test point with the electrostatic gun head, and then shift the device under test 100 in the vertical direction, so that the test point contacts the electrostatic gun head. After the adjustment is completed, the electrostatic gun is started to discharge and the test point is tested.
[0091] If there are multiple test points on the device under test 100 that need to be tested, each test point can be adjusted in turn according to the above adjustment method to make the current test point contact with the electrostatic gun tip to complete the test.
[0092] It should be noted that during the test, the position of the electrostatic gun can be kept fixed, and only the position of the ESD test fixture can be adjusted. Since the test point needs to be in contact with the electrostatic gun head during the test, after completing the test of the current test point, it is necessary to first adjust the movable bracket 10 to drive the device under test 100 to shift in the vertical direction, so that the current test point is separated from the electrostatic gun head, and then shift it in the horizontal direction, wait for the next test point to be aligned with the electrostatic gun head, and then shift it in the vertical direction so that the next test point is in contact with the electrostatic gun head.
[0093] When multiple test points need to be tested, the adjustment process for the position of each test point is the same.
[0094] The device to be tested may include: a PCB board, and one or more chips to be tested arranged on the PCB board; each chip to be tested may have one or more test points.
[0095] In order to make the device under test more stable on the support device 20, the support device 20 may include at least three support columns for fixing and supporting the PCB board. In some embodiments, two symmetrical support columns may be provided on the left and right sides, for a total of four support columns. Figure 1 The movable support 10 is shown with both sides close to the edge region.
[0096] In some embodiments, the device under test 100 can be tested with or without power. In addition, the device under test 100 can carry one or more chips under test, and the multiple chips under test can be heterogeneous chips (ie, chips of different types).
[0097] like Figure 2, which is a schematic diagram of the structure of a support device in an ESD test fixture provided in an embodiment of the present application.
[0098] In a non-limiting embodiment of the supporting device 20 , the supporting column includes an upper column 22 and a lower column 21 , and a diameter of the upper column 22 is smaller than a diameter of the lower column 21 .
[0099] In this example, the lower column 21 supports the device under test 100 , and the upper column 22 positions the device under test.
[0100] Lower column 21 and Figure 1 The movable bracket 10 located below is connected and fixed thereto; the upper column 22 is connected and fixed to the device under test 100. For example, a positioning hole 301 corresponding to the position of the upper column 22 and having a size that matches the position of the upper column 22 is set on the device under test 100, such as a PCB board. The upper column 22 supports and fixes the PCB board through the corresponding positioning hole 301. The structure is simple and convenient for installing and replacing the device under test. For devices under test 100 of different sizes and shapes, the position and spacing of the support column can be adjusted, or a plurality of different support column fixing positions can be set on the movable bracket 10 to facilitate the adjustment of the support column so that it can better adapt to devices under test 100 of different sizes and shapes.
[0101] It should be noted that, in some embodiments, the support device 20 and the device under test 100 may also adopt other connection structures, which are not limited in the embodiments of the present application. Figure 1 The connection method with the movable bracket 10 is not limited in the embodiment of the present application and can be designed accordingly according to the specific structure of the supporting device 20.
[0102] like Figure 3 , which is a schematic diagram of the structure of a movable bracket in an ESD test fixture provided in an embodiment of the present application.
[0103] In this example, the movable bracket 10 includes: a sliding device 11, and an elastic device 12 arranged on the sliding device 11. Wherein:
[0104] Also refer to Figure 1 The elastic device 12 is used to fix the above-mentioned supporting device 20, driving the device under test 100 to shift in the vertical direction so that the test point on the device under test 100 is in contact with or separated from the electrostatic gun head; the sliding device 11 is used to drive the device under test 100 to shift in the horizontal direction so that the test point is aligned with the electrostatic gun head.
[0105] Reference Figure 3In a non-limiting embodiment, the sliding device 11 may include: a base 111, a foot pad 112, and a lower clamping block 113. The foot pad 112 is disposed on the bottom surface of the base 111; and the lower clamping block 113 is disposed on the upper surface of the base 111.
[0106] The foot pad 112 can raise the base 111 to be higher than the work surface, so that when sliding, only the foot pad 112 is in contact with the work surface, which can greatly reduce the sliding resistance.
[0107] In order to make the sliding device 11 move more smoothly, the surface of the foot pad 112 can be designed as an arc structure. The material of the foot pad 112 can be hard plastic, or a metal material with an insulating layer, etc., with a smooth surface to ensure that the entire test fixture can move smoothly on the insulating pad.
[0108] In some embodiments, the base 111 may be a rectangular or square structure, and a foot pad 112 may be symmetrically arranged on each of the four side regions of the base 111. The foot pad 112 and the base 111 may be an integral structure or a split structure, which is not limited in the embodiments of the present application. The base 111 is the main load-bearing component of the lower half of the test fixture. On the one hand, the foot pad 112 can drive the base 111 to move the entire test fixture horizontally. On the other hand, the base 111 is the supporting component of the entire test fixture and needs to have sufficient weight to ensure the stability of the entire test fixture.
[0109] Continue to refer to Figure 3 In a non-limiting embodiment, the elastic device 12 may include: a top seat 121, a sliding column 122, an upper clamping block 123, a spring 124, and a column cap 125. Wherein:
[0110] The sliding column 122 is vertically mounted on the base 111 and fixed to the base 111 to fix and support the top seat 121;
[0111] The top seat 121 is provided with a through hole 1201 adapted to the sliding column 122, and the top seat 121 is sleeved on the sliding column 122 through the through hole 1201;
[0112] The spring 124 is a spiral structure, sleeved on the sliding column 122, and located below the top seat 121;
[0113] The column cap 125 is sleeved on the sliding column 122 and is located above the top seat 121. The column cap 125 can be an integrated structure fixed on the top seat 121, or a separate component, which is not limited in the present embodiment. The column cap 125 provides a vertical travel space for the top seat 121 and limits the movement space of the top seat 121. Figure 3 As shown, a flange structure 126 may be provided at the top end of the sliding post 122 .
[0114] The method of fixing the sliding column 122 and the base 111 is not limited in the embodiments of the present application. For example, in some embodiments, a through hole can be opened on the base 111, and the bottom end of the sliding column 122 can be passed through the through hole and fixed to the lower surface of the base 111 with a nut, or a corresponding mounting structure is set on the upper surface of the base 111, and the sliding column 122 is fixed by the mounting structure.
[0115] In this example, the sliding column 122 serves as a supporting component for vertical displacement, and the spring 124 serves as an elastic component for vertical displacement, which contracts when subjected to downward pressure and expands when the pressure is released.
[0116] The upper clamping block 123 is arranged on the lower surface of the top seat 121 and corresponds to the lower clamping block 113 on the base 111. The upper clamping block 123 and the lower clamping block 113 serve as buffer blocks and together form a vertical clamping assembly for limiting the maximum displacement in the vertical direction and preventing the top seat 121 from colliding with the base 111.
[0117] The upper clamping block 123 and the lower clamping block 113 may be made of the same or different materials, and specifically may be made of soft materials, such as foam, plastic, silicone, and the like.
[0118] The upper clamping block 123 may be adhered to the lower surface of the top seat 121 by glue; similarly, the lower clamping block 113 may be adhered to the upper surface of the base 111 by glue.
[0119] like Figure 4 FIG. 1 is a front view of a specific structure of an ESD test fixture provided in an embodiment of the present application. Figure 5 yes Figure 4 Top view of the ESD test fixture shown.
[0120] In this embodiment, the ESD test fixture may further include: a pressure sensor device 30, which is used to determine the pressure of the electrostatic gun tip on the test point to ensure reliable contact between the electrostatic gun tip and the test point and avoid damage to the electrostatic gun tip due to excessive pressure.
[0121] In other embodiments, the ESD test fixture may further include: an optical magnifying device for magnifying the area of the test point so that the tester can more clearly observe whether the test point and the electrostatic gun tip are aligned and in contact with each other.
[0122] The following are combined Figure 6 and Figure 7 The structures of the pressure sensing device 30 and the optical amplifying device are described in detail.
[0123] Reference Figure 6 , Figure 6It is a structural schematic diagram of a pressure sensing device in an ESD test fixture provided in an embodiment of the present application.
[0124] In this example, the pressure sensing device 30 includes: a control panel 31, a pressure sensor 33, a control unit 32, and an information indicating unit 34 arranged on the control panel 31; the control panel 31 is arranged on Figure 4 On the elastic device 12. Wherein:
[0125] The pressure sensor 33 is used to sense the downward pressure of the electrostatic gun head and convert the pressure into an electrical signal and output it to the control unit 32; its principle is to indirectly obtain the downward pressure of the electrostatic gun on the device under test by measuring the downward pressure of the device under test;
[0126] The control unit 32 is used to output a control signal to the information indication unit 34 according to the electrical signal;
[0127] The information indicating unit 34 is used to indicate the pressure information according to the control signal. The information indicating unit 34 can be implemented in a variety of ways and can play a role of prompting and warning. For example:
[0128] In some implementations, the information indicating unit 34 may be a display screen, such as an LCD screen or a digital tube, which may display the current pressure, or display prompt information, and the like.
[0129] In some embodiments, the information indicating unit 34 may also be a signal light, such as a bicolor LED light. The control signal is a voltage signal; when the voltage signal is less than a first set value (such as 0V), the bicolor LED light generates a first color light (such as green); when the voltage signal is greater than a second set value (such as 5V), the bicolor LED light generates a second color light (such as red).
[0130] It should be noted that the above-mentioned information indication unit 34 may also have other implementation methods and control methods, which are not limited in the embodiments of the present application.
[0131] Reference Figure 7 , is a structural schematic diagram of an optical amplification device in an ESD test fixture provided in an embodiment of the present application.
[0132] In this example, the optical magnifying device 40 includes: a fixed bracket and a magnifying glass 44; the fixed bracket is mounted on Figure 2 The elastic device 12 is mounted on the elastic device 12, for example, mounted on one end of the top seat 121 of the elastic device 12; the magnifying glass 44 is mounted on the fixed bracket.
[0133] like Figure 7 As shown, in a non-limiting embodiment, the fixing bracket may include: a fixing clamp 41 , a vertical arm 42 , and a retractable and rotatable horizontal arm 43 .
[0134] The vertical arm 42 is installed on the top seat 121 of the elastic device 12, and is used to connect and fix the horizontal arm 43, and can provide displacement space for the horizontal arm 43 in the vertical direction.
[0135] One end of the horizontal arm 43 is vertically connected to the top of the vertical arm 42, and the other end is connected to the magnifying glass 44, and provides a displacement space in the horizontal direction for the magnifying glass 44. Figure 4 The horizontal arm 43 can realize the horizontal rotation function. In actual operation, the horizontal arm 43 can be rotated first to move the magnifying glass 44, so as to facilitate the displacement of the ESD test fixture, so that the test point on the device under test 100 is aligned with the electrostatic gun, and then the magnifying glass 44 is rotated to the original position to observe whether the electrostatic gun is aligned with the test point on the device under test 100.
[0136] For example, in some embodiments, an adjustment button 45 may be provided on the horizontal arm 43, and the state of the horizontal arm 43 may be adjusted by the adjustment button 45 to adjust the length and horizontal rotation angle of the horizontal arm 43, or to fix the horizontal arm 43 and the magnifying glass 44. Specifically, by rotating the adjustment button 45 to put the adjustment button 45 in a "loose" state, the length and horizontal rotation angle of the horizontal arm 43 may be freely adjusted, and the rotation angle of the magnifying glass 44 may also be adjusted; when the adjustment button 45 is in a "tight" state, the horizontal arm 43 and the magnifying glass 44 are fixed.
[0137] In this embodiment, the magnifying glass 44 serves as an imaging component and may include a frame and a convex lens. The frame connects the horizontal arm 43 and the convex lens, and the convex lens realizes the image magnification function.
[0138] The ESD test fixture provided in the embodiment of the present application can place the device under test on the ESD test fixture when performing an ESD test on the device under test. By adjusting the ESD test fixture, the current test point can be easily brought into contact with the electrostatic gun tip, thereby improving the speed and efficiency of test point alignment. Moreover, in the process of adjusting the ESD test fixture, coarse adjustment and fixation are first performed, and then fine adjustment and control are performed, which can greatly improve the test efficiency and accuracy.
[0139] Accordingly, the embodiment of the present application also provides an ESD testing method. Figure 8 A flow chart of the ESD testing method provided in an embodiment of the present application is shown. Fig. 9 and Fig.10 It is a schematic diagram of the horizontal and vertical displacement of the device under test during the test process.
[0140] Also refer to Fig. 9 and Fig.10 , the ESD test process is as follows:
[0141] In step 801 , a device under test is placed on an ESD test fixture, wherein the device under test includes one or more test points.
[0142] Also refer to Figure 4 and Fig. 9 As shown, the device under test 100 is placed on the support device 20 of the ESD test fixture. There are multiple test points 101 on the device under test 100, and each test point 101 needs to be tested in sequence.
[0143] In step 802, the position of the electrostatic gun is adjusted so that the electrostatic gun head is facing downward and suspended in the air close to the device under test.
[0144] like Fig. 9 As shown, the position of the electrostatic gun 200 is adjusted so that the electrostatic gun head 201 is facing downward and suspended in the air close to the device under test 100 .
[0145] In step 803, a current test point is determined, and the ESD test fixture is adjusted to make the current test point contact with the electrostatic gun tip.
[0146] The specific adjustment process is as follows: first, the ESD test fixture is controlled to shift in the horizontal direction so that the current test point on the device under test is aligned with the electrostatic gun head; then the ESD test fixture is controlled to shift in the vertical direction to drive the device under test to rise so that the current test point contacts the electrostatic gun head.
[0147] The horizontal shift process includes the following steps: ① vertically press down the top seat 121 of the ESD test fixture, for example, by pressing the upper edges of the left and right sides of the top seat 121 with your fingers, to apply downward pressure, driving the device under test 100 to descend so that it is lower than the electrostatic gun head 201; ② horizontally move the entire ESD test fixture, driving the device under test 100 to translate so that the test point 101 on it is aligned with the electrostatic gun head, such as Fig. 9 shown.
[0148] The vertical displacement process includes the following steps: ③ Gradually release the downward pressure on the top seat 121 to allow it to rebound vertically, driving the device under test 100 to rise, so that the test point 101 on it contacts the electrostatic gun head 201, such as Fig.10 shown.
[0149] In step 804, after the adjustment is completed, the electrostatic gun 200 is started to discharge and the test of the current test point is completed.
[0150] In some embodiments, the following steps may also be included:
[0151] In the process of adjusting the ESD test fixture, before the above step 804, the pressure of the electrostatic gun head 201 on the current test point is obtained in real time; when the pressure is 0 or the pressure is greater than the set value, the ESD test fixture is removed, and the process returns to the above step 802 to readjust the vertical position of the electrostatic gun. For example, Figure 6 The information indicating unit 34 determines whether the current pressure is appropriate. If the pressure is too high or too low, the ESD test fixture needs to be removed and the process returns to step 802.
[0152] In some embodiments, the following steps may also be included:
[0153] In the process of adjusting the ESD test fixture, before step 804, Figure 7 The optical magnifying device 40 shown magnifies and observes the current test point area to observe whether the electrostatic gun tip 201 and the test point 101 are aligned. If they are not completely aligned, the above step 803 is repeated.
[0154] It should be noted that the discharge parameters of the electrostatic gun 200 can be set according to actual needs. Usually, the electrostatic gun is connected to the electrostatic generator and has corresponding control buttons and start buttons, which can discharge through the electrostatic gun head 201.
[0155] After completing the test of one test point, the above process can be repeated, firstly the device under test 100 is shifted horizontally and the next test point is aligned with the electrostatic gun head 201; then the device under test 100 is shifted vertically and the test point is in contact with the electrostatic gun head 201; finally the electrostatic gun 200 is started to discharge and the test of the test point is completed. The same process is repeated until all test points are tested.
[0156] The ESD testing method provided in the embodiment of the present application, when testing the test points on the device to be tested, adjusts the position of the test points through the ESD testing fixture, first performs coarse adjustment and fixation, and then performs fine adjustment and control, which effectively improves the test efficiency and the accuracy of the test results.
[0157] Furthermore, the optical magnifying device on the ESD test fixture is used to magnify and observe the test point area, thereby ensuring the accuracy of alignment between the test point and the electrostatic gun tip.
[0158] Furthermore, by utilizing the pressure sensing device on the ESD test fixture, the accuracy of the alignment between the test point and the electrostatic gun tip and the reliability of the contact between the test point and the electrostatic gun tip are better guaranteed, thereby better ensuring the accuracy of the test results.
[0159] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application shall be subject to the scope defined by the claims.
Claims
1. An ESD test fixture, characterized in that: include: A movable bracket, and a supporting device arranged on the movable bracket; The supporting device is used to place the device under test, and the device under test includes one or more test points; The movable bracket is used to drive the device under test to shift in the horizontal direction through the supporting device so that the current test point is aligned with the electrostatic gun head, and then drive the device under test to shift in the vertical direction so that the current test point is in contact with or separated from the electrostatic gun head.
2. The ESD test fixture according to claim 1, characterized in that: The device under test comprises: a PCB board, and one or more chips under test arranged on the PCB board; The supporting device comprises: at least three supporting columns, which are used for fixing and supporting the PCB board.
3. The ESD test fixture according to claim 2, characterized in that: The PCB board is provided with at least three positioning holes; The support column comprises an upper column and a lower column, the diameter of the upper column is smaller than the diameter of the lower column and is adapted to the diameter of the positioning hole; The lower column is connected and fixed to the movable bracket; the upper column passes through the positioning hole to support and fix the PCB board.
4. The ESD test fixture according to claim 1, characterized in that: The movable bracket comprises: a sliding device, and an elastic device arranged on the sliding device; The elastic device is used to fix the supporting device and drive the device to be tested to shift in the vertical direction so that the test point contacts or separates from the electrostatic gun head; The sliding device is used to drive the device to be tested to shift in the horizontal direction so that the test point is aligned with the electrostatic gun head.
5. The ESD test fixture according to claim 4, characterized in that: The sliding device comprises: a base, a foot pad, and a lower clamping block; The foot pad is arranged on the lower bottom surface of the base; The lower clamping block is arranged on the upper surface of the base.
6. The ESD test fixture according to claim 5, characterized in that: The surface of the foot pad is an arc-shaped structure.
7. The ESD test fixture according to claim 5, characterized in that: The foot pad and the base are an integrated structure.
8. The ESD test fixture according to claim 5, characterized in that: The elastic device comprises: a sliding column, a spring, a top seat, a column cap, and an upper clamping block; The sliding column is vertically mounted on the base and is used to fix and support the top seat; The top seat is provided with a through hole adapted to the sliding column, and the top seat is sleeved on the sliding column through the through hole; The spring is sleeved below the top seat on the sliding column; The column cap is sleeved on the top of the top seat on the sliding column and can slide up and down along the sliding column to provide a vertical movement travel space for the top seat and limit the upward movement space of the top seat; The upper clamping block is arranged on the lower surface of the top seat and corresponds to the lower clamping block, and is used to limit the maximum displacement in the vertical direction and prevent the top seat from colliding with the base.
9. The ESD test fixture according to claim 8, characterized in that: The lower clamping block and the upper clamping block are made of soft material.
10. The ESD test fixture according to claim 4, characterized in that: The fixture also includes: The pressure sensing device is used to determine the pressure of the electrostatic gun tip on the test point to ensure reliable contact between the electrostatic gun tip and the test point and avoid damage to the electrostatic gun tip.
11. The ESD test fixture according to claim 10, characterized in that: The pressure sensing device comprises: a control panel, and a pressure sensor, a control unit, and an information indicating unit arranged on the control panel; the control panel is arranged on the elastic device; The pressure sensor is used to sense the downward pressure of the electrostatic gun tip and convert the pressure into an electrical signal and output it to the control unit; The control unit is used to output a control signal to the information indication unit according to the electrical signal; The information indicating unit is used to indicate pressure information according to the control signal.
12. The ESD test fixture according to claim 11, characterized in that: The information indicating unit is a two-color LED lamp, and the control signal is a voltage signal; When the voltage signal is less than a first set value, the bicolor LED lamp generates a first color light; When the voltage signal is greater than a second set value, the dual-color LED lamp generates a second color light.
13. The ESD test fixture according to any one of claims 4 to 12, characterized in that: The fixture also includes: An optical magnifying device, used to magnify the area of the test point; The optical magnifying device comprises: a fixed bracket and a magnifying glass; the fixed bracket is installed on the elastic device, and the magnifying glass is installed on the fixed bracket.
14. The ESD test fixture according to claim 13, characterized in that: The fixing bracket comprises: a fixing clamp, a vertical arm and a retractable and rotatable horizontal arm; The vertical arm is mounted on the elastic device through a fixing clip, and is used to connect and fix the horizontal arm, and provide a displacement space for the horizontal arm in the vertical direction; One end of the horizontal arm is vertically connected to the top of the vertical arm, and the other end is connected to the magnifying glass, and provides a displacement space for the magnifying glass in the horizontal direction; The horizontal arm is provided with an adjusting button for adjusting the state of the horizontal arm, so as to adjust the length and rotation angle of the horizontal arm and the rotation angle of the magnifying glass, or to fix the horizontal arm and the magnifying glass.
15. An ESD testing method, characterized in that: The method comprises: Placing a device under test on an ESD test fixture, wherein the device under test includes one or more test points; Adjust the position of the electrostatic gun so that the head of the electrostatic gun is facing downward and suspended in the air close to the device to be tested; Determine the current test point, and make the current test point contact with the electrostatic gun head by adjusting the ESD test fixture; the adjusting of the ESD test fixture comprises: firstly controlling the ESD test fixture to shift in the horizontal direction so that the current test point on the device under test is aligned with the electrostatic gun head; then controlling the ESD test fixture to shift in the vertical direction to drive the device under test to rise so that the current test point contacts with the electrostatic gun head; After the adjustment is completed, the electrostatic gun is started to discharge and the test of the current test point is completed.
16. The ESD testing method according to claim 15, characterized in that: The method further comprises: In the process of adjusting the ESD test fixture, obtaining the pressure of the electrostatic gun tip on the current test point in real time; When the pressure is 0 or the pressure is greater than the set value, the ESD test fixture is moved away, and the process returns to the step of adjusting the position of the electrostatic gun.
17. The ESD testing method according to claim 15 or 16, characterized in that: The method further comprises: During the adjustment of the ESD test fixture, the current test point area is magnified and observed; If the electrostatic gun tip is not aligned with the current test point, readjust it.