Electrostatic discharge measuring method

Abstract

The invention relates to an electrostatic discharge measuring method, which is used for measuring electrostatic discharge applied to a test point of a case. The electrostatic discharge measuring method includes placing at least a portion of an electrostatic discharge measuring device in the case, coupling a first conductive element of the electrostatic discharge measuring device to the test point, and coupling a second conductive element of the electrostatic discharge measuring device to a ground terminal of the case to receive a reference voltage. Setting an electrostatic discharge simulator according to a type of the test point, applying an electrostatic discharge pulse to the chassis by using the electrostatic discharge simulator so as to generate a first voltage at the test point, and measuring a second voltage corresponding to the first voltage by using the electrostatic discharge measuring device, and measuring the influence of the electrostatic discharge pulse on the case according to the second voltage.

Description

Technical Field

[0001] The present application discloses an electrostatic discharge measurement method, and more particularly, an electrostatic discharge measurement method capable of setting an electrostatic discharge simulator according to the type of a test point. Background Art

[0002] The impact of electrostatic discharge (ESD) on electronic products is not only that the electrostatic discharge current is fed into the victim product, which may damage the victim product, but also that when electrostatic discharge occurs, the radiation noise generated by the discharge current may cause signal interference to the victim product. For example, according to the specifications defined by IEC 61000-4-2 or EN 61000-4-2 regulations, when the electrostatic discharge has a discharge of 4 kilovolts (kV), the product must be able to accept a discharge current of 15 amperes (A) within 1 nanosecond (ns), and the product must not have system function abnormalities in order to meet the regulatory requirements.

[0003] Currently, in the early stages of chassis development, the evaluation of ESD shielding effectiveness often relies on the experience of engineers. After checking the design drawings, they conduct visual discussions on the prototype chassis to evaluate possible ESD prevention and control measures, but cannot perform actual ESD measurements.

[0004] The actual measurement and evaluation of the chassis's ESD protection performance can only be performed after the system-related circuit boards' software and hardware are installed. Under such circumstances, the chassis's ESD shielding performance evaluation will be overly dependent on the engineers' experience, and will also fall into the dilemma of being forced to replace the early design with late debugging. If the chassis's ESD protection capability is not high enough in the future, it will be forced to modify the original design. Summary of the invention

[0005] An embodiment provides an electrostatic discharge measurement method for measuring the electrostatic discharge of a chassis, the chassis including a test point. The electrostatic discharge measurement method includes placing at least a portion of an electrostatic discharge measurement device in the chassis, coupling a first conductive element of the electrostatic discharge measurement device to the test point, coupling a second conductive element of the electrostatic discharge measurement device to a ground terminal of the chassis to receive a reference voltage, setting an electrostatic discharge simulator according to a type of the test point, applying an electrostatic discharge pulse to the chassis using the electrostatic discharge simulator to generate a first voltage at the test point, and measuring a second voltage corresponding to the first voltage using the electrostatic discharge measurement device to measure the effect of the electrostatic discharge pulse on the chassis according to the second voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1A schematic diagram of an electrostatic discharge measuring device measuring a point to be measured in a chassis according to an embodiment;

[0007] Figure 2 is a flow chart of an electrostatic discharge measurement method in an embodiment;

[0008] Figure 3 A schematic diagram showing a test point of the first type in an embodiment;

[0009] Figure 4 is a schematic diagram of a test point of the second type in an embodiment;

[0010] Figure 5 is a schematic diagram of a test point of the third type in the embodiment;

[0011] Figure 6 is a schematic diagram of a test point of the fourth type in the embodiment;

[0012] Figure 7 FIG. 1 is a schematic diagram showing that the test point is of the fifth type in the embodiment.

[0013] Explanation of symbols

[0014] 100: Electrostatic discharge measurement device

[0015] 110: first conductive element

[0016] 120: second conductive element

[0017] 130: Resistance

[0018] 140: Attenuator

[0019] 150: Oscilloscope

[0020] 150r: equivalent resistance

[0021] 200: Electrostatic discharge measurement method

[0022] 210 to 260: Steps

[0023] 310,410: Conductive objects

[0024] 420: Plastic isolation layer

[0025] 500: Chassis

[0026] 505: Board

[0027] 510: Electrostatic Discharge Simulator

[0028] 550: Plastic objects

[0029] 610,710: First conductive object

[0030] 620,720: Second conductive object

[0031] d1,d2: preset distance

[0032] G1: Conductive point

[0033] Iin: current

[0034] P1: point to be tested

[0035] PS: Pulse

[0036] V1: first voltage

[0037] V2: Second voltage

[0038] Vr: reference voltage DETAILED DESCRIPTION

[0039] Figure 1 1 is a schematic diagram of an electrostatic discharge measuring device 100 measuring a test point P1 of a chassis 500 in an embodiment. The electrostatic discharge measuring device 100 can be used to measure electrostatic discharge (ESD) at the test point P1. The electrostatic discharge measuring device 100 can include a first conductive element 110, a resistor 130, a second conductive element 120, an attenuator 140, and an oscilloscope 150.

[0040] For example, the first conductive element 110 may be a first alligator clip, the second conductive element 120 may be a second alligator clip, the first conductive element 110 may be coupled to the test point P1 of the chassis 500, and the conductive point G1 of the second conductive element 120 may receive a reference voltage Vr, such as a ground voltage. For example, the conductive point G1 may be a system ground point on the chassis 500.

[0041] Due to the electrostatic discharge at the test point P1, a current Iin may flow through the resistor 130, thereby generating a first voltage V1 at the end of the resistor 130. The attenuator 140 may convert the first voltage V1 into a second voltage V2. The first voltage V1 may be higher than the second voltage V2, and the value of the first voltage V1 divided by the second voltage V2 may be 20 decibels (dB), or 10. If the resistance value of the resistor 130 is represented by R1, the relationship between the current, voltage and resistance value may be as described in the following formula:

[0042] V1=Iin×R1=k×V2…eq-1

[0043] The parameter k may be a value obtained by dividing the first voltage V1 by the second voltage V2 , and k may be 20 dB, or the parameter k may be 10.

[0044] For example, the attenuator 140 may be a SubMiniature version A (SMA) attenuator. The oscilloscope 150 may be a digital storage oscilloscope (DSO) or other suitable oscilloscopes. Using the attenuator 140 to convert the first voltage V1 into the second voltage V2 can avoid damage to the oscilloscope 150. For example, the oscilloscope 150 may have an equivalent resistor 150r.

[0045] The resistance value of the resistor 130 may be between 1 ohm and 3 ohms. For example, the resistance value of the resistor 130 may be between 1.5 and 2.5 ohms. For example, the resistance value of the resistor 130 may be 2 ohms. The resistance value of the equivalent resistor 150r of the oscilloscope 150 may be between 40 ohms and 60 ohms. For example, the resistance value of the equivalent resistor 150r may be 50 ohms.

[0046] Herein, when referring to the first operating voltage and the second operating voltage of the ESD simulator 510, the first operating voltage may be the +4kV voltage value of the ESD simulator 510, and the second operating voltage may be the -4kV voltage value of the ESD simulator 510, wherein the ESD simulator 510 may be (but not limited to) a Dito EM-TEST ESD simulator.

[0047] Figure 2 2 is a flow chart of an electrostatic discharge measurement method 200 in an embodiment. The electrostatic discharge measurement method 200 can measure the electrostatic discharge of the test point P1 of the chassis 500. The electrostatic discharge measurement method 200 includes:

[0048] Step 210: placing at least a portion of the electrostatic discharge measurement device 100 in the chassis 500;

[0049] Step 220: coupling the first conductive element 110 of the electrostatic discharge measurement device 100 to the test point P1;

[0050] Step 230: coupling the second conductive element 120 of the electrostatic discharge measuring device 100 to the ground terminal G1 of the chassis 500 to receive the reference voltage Vr;

[0051] Step 240: Setting the electrostatic discharge simulator 510 according to the type of the test point P1;

[0052] Step 250: Use the ESD simulator 510 to apply an ESD pulse PS to the chassis 500 to generate a first voltage V1 at the test point P1; and

[0053] Step 260 : Use the ESD measuring device 100 to measure the second voltage V2 corresponding to the first voltage V1 , so as to measure the influence of the ESD pulse PS on the chassis 500 according to the second voltage V2 .

[0054] In step 210, the part of the electrostatic discharge measuring device 100 except the oscilloscope 150 can be placed in the chassis 500 for measurement. In step 220, if the first conductive element 110 is a first alligator clip, the jaw of the alligator clip can be clamped to the test point P1. In step 230, if the second conductive element 120 is a second alligator clip, the jaw of the alligator clip can be clamped to the ground terminal G1. In step 240, the first operating voltage and the second operating voltage of the electrostatic discharge simulator 510 can be set. In step 260, if the voltage value of the measured second voltage V2 is higher, the first voltage V1 is higher, and the user can judge the electrostatic discharge tolerance and reliability of the corresponding position of the chassis 500 accordingly.

[0055] Figure 3 Schematic diagram of the test point P1 of the first type in the embodiment. When the test point P1 is of the first type, the test point P1 may be a conductive object 310 connected to the plate surface 505 of the chassis 500, and the conductive object 310 may have a pointed end to form a protruding shape. For example, the conductive object 310 may be a screw made of a metal material and has a pointed end. In another example, the conductive object 310 may be a protruding element of a metal material. According to observation, electrostatic discharge often discharges at the protruding part of the conductive material element, so an electrostatic discharge test is often required here to measure the primary discharge and / or secondary discharge of the electrostatic discharge.

[0056] When the test point P1 is of the first type, the ESD simulator 510 may be set to have a first operating voltage and a second operating voltage, wherein the first operating voltage may correspond to a voltage between 3.9 volts and 4.2 volts, and the second operating voltage may correspond to a voltage between 4.3 volts and 4.6 volts. For example, the first operating voltage of the ESD simulator 510 may correspond to 4.07 volts, and the second operating voltage of the ESD simulator 510 may correspond to 4.42 volts.

[0057] Figure 4 4 is a schematic diagram of an embodiment in which the test point P1 is of the second type. When the test point P1 is of the second type, the test point P1 may be a conductive object 410 connected to the board 505 of the chassis 500, the conductive object 410 may have a tip to form a protrusion, and the plastic isolation layer 420 wraps at least a portion of the conductive tip object. For example, the conductive object 410 may be a screw made of a metal material, having a tip, and the plastic isolation layer 420 wraps at least a portion of the screw. In another example, the conductive object 410 may be a protruding element made of a metal material, and the plastic isolation layer 420 may wrap a portion of the conductive object 410.

[0058] When the test point P1 is of the first type, the ESD simulator 510 may be set to have a first operating voltage and a second operating voltage, wherein the first operating voltage may correspond to a voltage between 77.5 volts and 78.7 volts, and the second operating voltage may correspond to a voltage between 74 volts and 75.5 volts. For example, the first operating voltage of the ESD simulator 510 may correspond to 78.17 volts, and the second operating voltage of the ESD simulator 510 may correspond to 74.87 volts.

[0059] Regarding the first type and the second type, when the ground resistance is less than 50 milliohms (mΩ), the EDC current measurement foundation voltage should be less than or equal to 4 volts.

[0060] Figure 5 Schematic diagram of the test point P1 of the third type in an embodiment. When the test point P1 is the third type, the test point P1 can be a plastic object 550 connected to the board 505 of the chassis 500, and the plastic object 550 can have a tip to form a protrusion. For example, the plastic object 550 can be a screw made of plastic material with a tip.

[0061] When the test point P1 is of the third type, the electrostatic discharge simulator 510 may be set to have a first operating voltage and a second operating voltage, wherein the first operating voltage may correspond to a voltage between 0.8 volts and 0.9 volts, and the second operating voltage may correspond to a voltage between 0.85 volts and 0.95 volts. For example, the first operating voltage may correspond to 0.85 volts, and the second operating voltage may correspond to 0.89 volts.

[0062] Figure 6 Schematic diagram of the test point P1 of the fourth type in the embodiment. When the test point P1 is the fourth type, the test point P1 may be a first conductive object 610 connected to the board 505 of the chassis 500, the first conductive object 610 may have a first tip to form a first protrusion, and the second conductive object 620 may have a second tip to form a second protrusion. The first tip points to the second tip, and the first tip and the second tip may be separated by a predetermined distance d1. For example, the first conductive object 610 may be a metal screw, and the second conductive object 620 may be another metal screw, wherein the tips of the two metal screws may be arranged opposite to each other and separated by a predetermined distance d1. Since the tip of the conductive element is prone to electrostatic discharge, this type of test point P1 can be measured.

[0063] When the test point P1 is of the fourth type, the electrostatic discharge simulator 510 may be set to have a first operating voltage and a second operating voltage, wherein when the object under test is a locking bolt floating on the housing, the result of the first operating voltage (e.g., +4kV voltage value) may be between 8 volts and 9 volts, and the result of the second operating voltage (e.g., +4kV voltage value) may be between 8 volts and 9 volts. For example, the result of the first operating voltage may be 8.85 volts, and the result of the second operating voltage may be 8.11 volts. When the object under test is a locking bolt grounded to the housing, the result of the first operating voltage may be between 2 volts and 3 volts, and the result of the second operating voltage may be between 2 volts and 3 volts. For example, the result of the first operating voltage may be 2.71 volts, and the result of the second operating voltage may be 2.36 volts.

[0064] In addition, when the test point P1 is of the fourth type, for example, if the first operating voltage of the electrostatic discharge simulator 510 is a voltage value of +8kV and the second operating voltage is a voltage value of -8kV, when the object under test is a locking bolt floating on the housing, the result of the first operating voltage may be between 15 and 16 volts (e.g., 15.46 volts), and the result of the second operating voltage may be between 16 and 17 volts (e.g., 16.04 volts). When the object under test is a locking bolt grounded on the housing, the result of the first operating voltage may be between 4 and 5 volts (e.g., 4.20 volts), and the result of the second operating voltage may be between 4 and 5 volts (e.g., 4.14 volts).

[0065] In addition, when the test point P1 is of the fourth type, for example, if the first operating voltage of the electrostatic discharge simulator 510 is a +4kV voltage value, and the second operating voltage is a -4kV voltage value, then when the object under test is a floating HDD handle and bracket, the result of the first operating voltage may be between 75 and 80 volts (e.g., 79.56 volts), and the result of the second operating voltage may be between 75 and 80 volts (e.g., 77.75 volts).

[0066] When the test point P1 is of the fourth type, for example, when the object to be tested is a hard disk handle that is floating and the bracket is grounded, the result of the first operating voltage may be between 45 and 50 volts (for example, 48.42 volts), and the result of the second operating voltage may be between 55 and 58 volts (for example, 56.87 volts).

[0067] When the test point P1 is of the fourth type, for example, when the object to be tested is a hard disk handle and the bracket is grounded, the result of the first operating voltage can be between 8 and 10 volts (for example, 8.42 volts), and the result of the second operating voltage can be between 6 and 8 volts (for example, 6.34 volts).

[0068] Figure 7is a schematic diagram of the test point P1 of the fifth type in an embodiment. When the test point P1 is of the fifth type, the test point P1 may be a first conductive object 710 connected to the plate surface 505 of the chassis 500, the first conductive object 710 may have a tip to form a protrusion, the second conductive object 720 may have a sheet shape, and the second conductive object 720 and the first conductive object 710 may be separated by a predetermined distance d2. For example, the first conductive object 710 may be a metal screw, and the second conductive object 720 may be a sheet-shaped metal sheet inside the chassis 500, disposed above the first conductive object 710.

[0069] When the test point P1 is of the fifth type, the electrostatic discharge simulator 510 can be set to have a first operating voltage and a second operating voltage. When the metal portion of the second discharge of the electrostatic discharge is bonded to the bottom plane, and the bottom plane is close to and completely connected to the gap of the top plane, the electrostatic discharge warning value (EDC) corresponding to the first operating voltage may be between 4 and 5 volts (for example, 4.52 volts), the electrostatic discharge reliability value (EDR) corresponding to the first operating voltage may be between 15 and 16 volts (for example, 15.89 volts), the electrostatic discharge warning value (EDC) corresponding to the second operating voltage may be between 4 and 5 volts (for example, 4.35 volts), and the electrostatic discharge reliability value (EDR) corresponding to the second operating voltage may be between 20 and 21 volts (for example, 20.27 volts).

[0070] When the test point P1 is of the fifth type, and when the metal portion of the second discharge of the electrostatic discharge is adhered to the bottom plane and is close to but not continuously connected to the gap of the top plane, the electrostatic discharge warning value (EDC) corresponding to the first operating voltage may be between 4 and 5 volts (for example, 4.84 volts), the electrostatic discharge reliability value (EDR) corresponding to the first operating voltage may be between 20 and 22 volts (for example, 21.24 volts), the electrostatic discharge warning value (EDC) corresponding to the second operating voltage may be between 4 and 5 volts (for example, 4.32 volts), and the electrostatic discharge reliability value (EDR) corresponding to the second operating voltage may be between 18 and 19 volts (for example, 18.32 volts).

[0071] When the test point P1 is of the fifth type, and when the second discharge metal portion of the electrostatic discharge is bonded to the bottom plane and close to the opening on the top plane, the electrostatic discharge warning value (EDC) corresponding to the first operating voltage may be between 27 and 28 volts (for example, 27.87 volts), the electrostatic discharge reliability value (EDR) corresponding to the first operating voltage may be between 48 and 50 volts (for example, 49.51 volts), the electrostatic discharge warning value (EDC) corresponding to the second operating voltage may be between 27 and 29 volts (for example, 28.05 volts), and the electrostatic discharge reliability value (EDR) corresponding to the second operating voltage may be between 58 and 60 volts (for example, 59.82 volts).

[0072] The electrostatic discharge measurement device and the electrostatic discharge measurement method of the embodiment can be applied to a server, and the server can be used for artificial intelligence (AI) computing, edge computing, and can also be used as a 5G server, a cloud server, or an Internet of Vehicles server.

[0073] In summary, by using the electrostatic discharge measuring device 100 and the electrostatic discharge measuring device 200, it is convenient to perform simulation tests on the electrostatic discharge tolerance and reliability of each position of the chassis 500, so that the inconvenience caused by performing electrostatic discharge tests after the electronic components (such as processors, memory, etc.) are installed in the chassis can be avoided, and the risk of damage to the electronic components can also be reduced. In addition, by using the electrostatic discharge measuring method 200, the first discharge and the second discharge of electrostatic discharge can be conveniently and accurately tested for various types of test points P1 of the chassis 500. Therefore, the electrostatic discharge measuring method 200 of the embodiment is really helpful in dealing with the difficult problems in the field of electrostatic discharge testing.

[0074] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A method for measuring electrostatic discharge, characterized in that: The method is used to measure the electrostatic discharge of a chassis, the chassis comprising a test point, and the electrostatic discharge measurement method comprises: placing at least a portion of an electrostatic discharge measurement device within the chassis; coupling a first conductive element of the electrostatic discharge measurement device to the test point; coupling a second conductive element of the electrostatic discharge measuring device to a ground terminal of the chassis to receive a reference voltage; Setting an electrostatic discharge simulator according to a type of the test point; Applying an electrostatic discharge pulse to the chassis using the electrostatic discharge simulator to generate a first voltage at the test point; and The electrostatic discharge measuring device is used to measure a second voltage corresponding to the first voltage, so as to measure the electrostatic discharge pulse according to the second voltage.

2. The electrostatic discharge measurement method according to claim 1, characterized in that: The type of the test point is: A conductive object is connected to a plate surface of the chassis, and the conductive object has a pointed end to form a protruding shape.

3. The electrostatic discharge measurement method according to claim 2, characterized in that: The electrostatic discharge simulator is set to have a first operating voltage and a second operating voltage, wherein the first operating voltage corresponds to a voltage between 3.9 volts and 4.2 volts, and the second operating voltage corresponds to another voltage between 4.3 volts and 4.6 volts.

4. The electrostatic discharge measurement method according to claim 1, characterized in that: The type of the test point is: A conductive object is connected to a plate surface of the chassis, the conductive object has a tip to form a protrusion, and a plastic isolation layer wraps at least a part of the conductive object.

5. The electrostatic discharge measurement method according to claim 4, characterized in that: The electrostatic discharge simulator is set to have a first operating voltage and a second operating voltage, wherein the first operating voltage corresponds to a voltage between 77.5 volts and 78.7 volts, and the second operating voltage corresponds to another voltage between 74 volts and 75.5 volts.

6. The electrostatic discharge measurement method according to claim 1, characterized in that: The type of the test point is: A plastic object is connected to a plate surface of the case, and the plastic object has a tip to form a protrusion.

7. The electrostatic discharge measurement method according to claim 6, characterized in that: The electrostatic discharge simulator is set to have a first operating voltage and a second operating voltage, the first operating voltage is between 0.8 volts and 0.9 volts, and the second operating voltage is between 0.85 volts and 0.95 volts.

8. The electrostatic discharge measurement method according to claim 1, characterized in that: The type of the test point is: A first conductive object is connected to a panel of the chassis, and the first conductive object has a first tip to form a first protrusion; and A second conductive object has a second tip to form a second protrusion; The first tip points to the second tip, and a predetermined distance is provided between the first tip and the second tip.

9. The electrostatic discharge measurement method according to claim 1, characterized in that: The type of the test point is: A first conductive object is connected to a panel of the chassis, and the first conductive object has a tip to form a protrusion; and A second conductive object has a sheet shape, and the second conductive object and the first conductive object are separated by a predetermined distance.

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