ESD noise detection device

Abstract

The utility model provides an ESD noise detection device which is characterized by at least comprising a shielding box body, a wave-absorbing material pad, a magnetic field amplification module and an annular probe, the wave-absorbing material pad is arranged on the magnetic field amplification module, the annular probe is located at the position s away from the upper portion of the wave-absorbing material pad, and the annular probe and the wave-absorbing material pad are arranged in parallel; an opening is formed in the side wall of the shielding box body, and an electrostatic magnetic field enters the shielding box body through the opening. The ESD noise detection device is used for ESD noise detection. Since electromagnetic interference only enters from the opening of the shielding box body, other interference factors are small. And the detection device can quantitatively evaluate the ESD noise.

Description

Technical Field

[0001] The present invention relates to the technical field of noise detection, and in particular to an ESD noise detection device. Background Art

[0002] The parameters used by absorbing materials to characterize electromagnetic performance include dielectric constant, magnetic permeability, reflection loss, and transmission loss. At present, the influence of absorbing materials of specific products on ESD noise is usually characterized. The following problems exist in actual product testing:

[0003] (1) There are many factors that affect the actual product from ESD noise interference;

[0004] (2) In actual product testing, the difference in interference caused by different ESD voltage levels is not obvious, resulting in insufficient accuracy in characterizing the failure level of the device. In addition, ESD noise does not change linearly with the test level, so only qualitative comparison can be made, not quantitative evaluation. Summary of the invention

[0005] In order to overcome the problems existing in the related art, this specification provides an ESD noise detection device, which solves the problems that there are many interference factors in the existing ESD noise detection, avoids the problem that the interference difference caused by the voltage levels of ESD of different products is not obvious, and the ESD noise cannot be quantitatively evaluated.

[0006] According to an embodiment of the present specification, an ESD noise detection device is provided, which at least includes a shielding box, an absorbing material pad, a magnetic field amplification module, and an annular probe. The absorbing material pad is arranged on the magnetic field amplification module, the annular probe is located at a distance s above the absorbing material pad, and the annular probe is arranged parallel to the absorbing material pad. An opening is provided on the side wall of the shielding box, and the electrostatic magnetic field enters the shielding box through the opening.

[0007] Preferably, the magnetic field amplification module is a heat sink.

[0008] Preferably, the magnetic field amplification module is a metal block.

[0009] Preferably, the annular probe is connected to an external display device via a coaxial core wire.

[0010] Preferably, the shielding box is provided with a detachable panel, and the absorbing material pad and the magnetic field amplification module are placed into the shielding box through the detachable panel.

[0011] Furthermore, a filling strip is provided around a circle of the detachable panel to prevent electromagnetic escape.

[0012] Preferably, it also includes an insulating support module, which is placed in the shielding box, and the absorbing material pad and the magnetic field amplification module are arranged on the insulating support module.

[0013] Furthermore, the insulating support module is a cuboid or a cube and is placed on the bottom wall of the shielding box.

[0014] Furthermore, an insulating pad is provided between the insulating support module and the bottom wall of the shielding box.

[0015] Preferably, the insulating support module is a partition disposed in the shielding box.

[0016] The technical solutions provided by the embodiments of this specification may have the following beneficial effects:

[0017] The embodiments of this specification provide a device for ESD noise detection, because electromagnetic interference only enters from the opening of the shielding box, and is less affected by other interference factors. Moreover, the detection device can quantitatively evaluate ESD noise.

[0018] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the specification and, together with the description, serve to explain the principles of the specification.

[0020] Figure 1 is a side cross-sectional structural diagram of an embodiment of the application;

[0021] Figure 2 It is a front view of the application.

[0022] Reference numerals:

[0023] 1-shielded box; 11-detachable panel; 111-horizontal gap; 2-absorbing material pad; 3-magnetic field amplification module; 4-ring probe; 41-SMA connector; 5-insulation support module; 6-static gun; 7-filling strip DETAILED DESCRIPTION

[0024] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with this specification. Instead, they are merely examples of devices and methods consistent with some aspects of this specification as detailed in the appended claims.

[0025] The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this specification. The singular forms "a", "the" and "the" used in this specification and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0026] It should be understood that although the terms first, second, third, etc. may be used in this specification to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this specification, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0027] First of all, it is necessary to explain the ESD noise mentioned in the technical solution of this application. ESD (Electrostatic Discharge) noise refers to the electromagnetic interference caused by electrostatic discharge. Electrostatic discharge refers to the sudden discharge phenomenon caused by static electricity accumulation. This discharge will produce sudden high voltage and current, which may cause damage to electronic equipment, circuits and other sensitive equipment. ESD noise can interfere with the normal operation of electronic equipment, so when designing and using electronic equipment, it is necessary to consider how to prevent and reduce the impact of ESD.

[0028] The present application embodiment provides an ESD noise detection device, such as Figure 1-Figure 2As shown, at least a shielding box 1, an absorbing material pad 2, a magnetic field amplification module 3 and a ring probe 4 are included. In order to simulate the scene inside the device, the absorbing material pad 2 is arranged on the magnetic field amplification module 3, and the ring probe 4 is led out from the upper side wall of the shielding box 1, and the ring probe 4 is arranged in parallel with the absorbing material pad 2. An opening is provided on the side wall of the shielding box, and the electrostatic magnetic field enters the shielding box through the opening. Here, the shielding box is a metal box. The ring probe is wound by a core wire, and the ring probe wound by the core wire is used to receive signals. If the ring probe is coated with a core wire skin, it is mainly used to receive electromagnetic signals. If the core wire skin of the ring probe is peeled off, it can be used to receive electromagnetic signals and electrical signals. The electrostatic magnetic field is generated by an electrostatic gun 6 outside the shielding box. In order to avoid being affected by other factors, the electrostatic gun is preferably hit on the side wall of the shielding box to form a magnetic field closed loop. The surface of the magnetic field amplification module is metal. When disturbed by the electrostatic magnetic field, surface current will be generated on the metal surface, so that a high electromagnetic field is generated locally. When the locally high electromagnetic field is generated through the annular probe, a magnetic flux is generated, and an electromagnetic signal is received through the generated magnetic flux. The received electromagnetic field signal can be connected to an external display through the coaxial core wire of the annular probe for display. The display here can be an oscilloscope, etc. The magnetic field amplification module here can be a radiator or a metal block, etc., as long as the surface is metal and can be used to generate surface current. The annular probe is mainly used to simulate the circuit loop in the device, such as the loop of the power supply circuit. The annular probe can be fixedly set with the shielding box through, for example, an SMA connector 41. In the embodiment of the present application, the annular probe is located at a distance s above the absorbing material pad, and the distance s here is mainly to simulate the thickness of the chip. In addition, the shape of the annular probe can be circular or other shapes, which does not constitute a limitation. Because it is a simulation of the circuit loop scene in the chip, it is limited by the size of the chip, and the diameter of the annular probe is preferably below the millimeter level. In order to reduce the interference factors of the electrostatic magnetic field entering the shielding box, the opening is preferably a horizontal gap 111. Because electromagnetic interference only enters from the opening of the shielding box, it is less affected by other interference factors. Because the absorbing material can be replaced under the test environment, quantitative evaluation of ESD can be achieved.

[0029] In order to simulate the position of the magnetic field amplification module in the device, such as a radiator, it is necessary to insulate the magnetic field amplification module and raise it. In the embodiment of the present application, two insulating support modules provide two embodiments for raising the magnetic field amplification module. Of course, this is only for example and does not constitute a limitation.

[0030] Embodiment 1:

[0031] like Figure 1 As shown, the insulating support module 5 is a rectangular parallelepiped or a cube and is placed on the bottom wall of the shielding box.

[0032] In order to facilitate the adjustment of the distance s between the annular probe and the absorbing material pad, an insulating pad, such as a rubber pad, may be provided between the insulating support module and the bottom wall of the shielding box.

[0033] As a preferred embodiment, a C-shaped metal fence (not shown) may be provided at the bottom of the shielding box, so as to ensure that the position of the insulating support is fixed each time it is pushed into the box.

[0034] Embodiment 2:

[0035] The insulating support module is a partition (not shown) arranged in the shielding box, and both sides of the partition are arranged on the side walls of the shielding box, and can be fixed by means of adhesive or screws.

[0036] The insulating support modules in the above two embodiments may be made of hard foam / wood materials with low dielectric constant (close to air), etc., which do not deform with temperature changes.

[0037] In the embodiment of the present application, the shielding box 1 is provided with a detachable panel 11 , and the absorbing material pad and the magnetic field amplification module are placed into the shielding box through the detachable panel 11 .

[0038] In order to facilitate the installation and removal of the detachable panel, the detachable panel is preferably arranged on the side wall of the shielding box. As a further preferred embodiment, the opening on the side wall can be arranged on the detachable panel. In terms of technology, it can be formed in one step.

[0039] like Figure 2 As shown, in order to prevent electromagnetic escape, a filling strip 7 is arranged around the detachable panel. As a preferred embodiment, the filling strip can be made of, for example, foam or rubber strip, to ensure good overlap and sealing with the shielding box, thereby ensuring the consistency of the test.

[0040] The absorbing material in this application refers to a type of material that can absorb or significantly reduce the electromagnetic wave energy received on its surface, thereby reducing electromagnetic wave interference. In engineering, in addition to requiring the absorbing material to have a high absorption rate of electromagnetic waves in a wide frequency band, it is also required to have properties such as light weight, temperature resistance, moisture resistance, and corrosion resistance. For example: ferrite materials, metal powder materials, etc.

[0041] Absorbing materials can also be superimposed with heat conduction functions, which are usually called thermal conductive absorbing materials. Thermal conductive absorbing materials are composite materials that have the characteristics of thermal interface materials and have excellent absorption properties for electromagnetic waves. They can be directly applied between heat sources and heat sinks. While conducting heat, they can absorb leaked electromagnetic radiation to eliminate electromagnetic interference. Thermal conductive pads such as silicone or graphite can be integrated with absorbing materials as thermal conductive absorbing material pads.

[0042] As an example of a simulation test, during the test, the opening of the shielding box is shielded with conductive cloth, and then the conductive cloth is torn off for testing. If the difference between the two results is greater than 20dB, it means that the noise mainly comes from the horizontal gap on the side wall of the shielding box, and the test can be carried out. If the above requirements are not met, the overlap and shielding of the coaxial core wire, SMA connector and detachable panel should be investigated until the requirements are met and the test is started. The discharge mode of the electrostatic gun is selected as contact discharge, and the "AUTO" mode is selected, and the frequency is recommended to be 1Hz. In addition to the fixed position of the discharge point during the test, it is necessary to ensure that the angle of the electrostatic gun is also fixed. Select the "AUTO" mode for the oscilloscope, and record the "peak-peak" value of the voltage amplitude after the reading value is stable. After multiple rounds of testing, the average value is the test result. Replace the absorbing material and continue the test. Quantitative analysis can be achieved by replacing the absorbing material for comparison.

[0043] The above is a description of a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0044] Those skilled in the art will readily appreciate other embodiments of the specification after considering the specification and practicing the invention claimed herein. The specification is intended to cover any variations, uses or adaptations of the specification that follow the general principles of the specification and include common knowledge or customary techniques in the art that are not claimed in the specification. The specification and examples are to be considered exemplary only, and the true scope and spirit of the specification are indicated by the following claims.

[0045] It should be understood that the present description is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present description is limited only by the appended claims.

[0046] The above description is only a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this specification should be included in the scope of protection of this specification.

Claims

1. An ESD noise detection device, characterized in that: The invention at least comprises a shielding box, an absorbing material pad, a magnetic field amplification module and an annular probe. The absorbing material pad is arranged on the magnetic field amplification module, the annular probe is located at a distance s above the absorbing material pad, and the annular probe is arranged parallel to the absorbing material pad. An opening is arranged on the side wall of the shielding box, and the electrostatic magnetic field enters the shielding box through the opening.

2. The ESD noise detection device according to claim 1, characterized in that: The magnetic field amplification module is a heat sink.

3. The ESD noise detection device according to claim 1, characterized in that: The magnetic field amplification module is a metal block.

4. The ESD noise detection device according to claim 1, characterized in that: The ring probe is connected to an external display device via a coaxial core cable.

5. The ESD noise detection device according to claim 1, characterized in that: The shielding box is provided with a detachable panel, and the absorbing material pad and the magnetic field amplification module are placed in the shielding box through the detachable panel.

6. The ESD noise detection device according to claim 5, characterized in that: A filler strip is provided around the removable panel to prevent electromagnetic escape.

7. The ESD noise detection device according to claim 1, characterized in that: It also includes an insulating support module, which is placed in the shielding box, and the absorbing material pad and the magnetic field amplification module are arranged on the insulating support module.

8. The ESD noise detection device according to claim 7, characterized in that: The insulating support module is a rectangular parallelepiped or a cube and is placed on the bottom wall of the shielding box.

9. The ESD noise detection device according to claim 8, characterized in that: An insulating pad is provided between the insulating support module and the bottom wall of the shielding box.

10. The ESD noise detection device according to claim 7, characterized in that: The insulating support module is a partition plate arranged in the shielding box.

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