CN116321676A - Circuit board assembly, radiation spurious emission anomaly detection method and electronic device - Google Patents

Abstract

The application discloses a circuit board assembly, a radiation stray emission anomaly detection method and electronic equipment. The circuit board assembly includes: a main board, on which a signal detection circuit is arranged; the shielding cover is arranged above the main board and connected with the main board, and a cavity is formed by enclosing the shielding cover and the main board; the bracket is arranged above the shielding cover and connected with the main board, a signal processing circuit is arranged on the bracket and is used for receiving stray signals leaked from the shielding cover, filtering the stray signals to obtain harmonic signals, and sending the harmonic signals to the signal detection circuit; the signal detection circuit is used for receiving the harmonic signals, detecting the energy of the harmonic signals, and determining that the electronic equipment has radiation spurious emission abnormality when the energy of the harmonic signals exceeds a threshold value. According to the electronic device, the signal processing circuit is arranged on the support, and the signal detection circuit is arranged on the main board, so that whether the electronic device is abnormal in radiation spurious emission or not can be detected in real time.

Description

Circuit board assembly, radiation spurious emission anomaly detection method and electronic device

technical field

The application belongs to the field of electronic technology, and in particular relates to a circuit board assembly, a method for detecting abnormal radiation stray emission, and electronic equipment.

Background technique

Radio frequency interference is a sore point and difficult problem in the mobile communication industry at present. The radio frequency interference generated by one electronic device may seriously affect the normal communication of other electronic devices. The radio frequency interference certification test item (EMC test) is also one of the certification test items most concerned by all manufacturers. Among them, Radiated Spurious Emission (RSE) is the most stringent and prone to problems.

During the production process of electronic equipment, manufacturers will test the RSE level of electronic equipment. However, after the electronic equipment is produced, RSE abnormality may occur in the electronic equipment due to reasons such as transportation and environmental humidity. The manufacturer cannot detect the RSE level of the electronic equipment after the production of the electronic equipment is completed.

Contents of the invention

The present application aims to provide a circuit board assembly, a method for detecting abnormal radiation stray emission and electronic equipment, so as to solve the problem that the RSE level of the electronic equipment cannot be detected after the electronic equipment is produced.

In order to solve the above-mentioned technical problems, the application is implemented as follows:

In the first aspect, the embodiment of the present application proposes a circuit board assembly, including:

A main board, the main board is provided with a signal detection circuit;

A shielding cover is arranged above the main board and connected to the main board, and a cavity is formed between the shielding cover and the main board;

a bracket, arranged above the shielding cover and connected to the main board, a signal processing circuit is provided on the bracket, the signal processing circuit is used to receive stray signals leaked from the shielding cover, and filter the scattered signal to obtain a harmonic signal, and send the harmonic signal to the signal detection circuit;

The signal detection circuit is used to receive the harmonic signal, detect the energy of the harmonic signal, and determine that the electronic device has abnormal radiation spurious emission when the energy of the harmonic signal exceeds a threshold.

In the second aspect, an embodiment of the present application proposes a method for detecting abnormal spurious emission of radiation, which is applied to the circuit board assembly described in the first aspect of the present invention, and the method includes: receiving from A stray signal leaked from the shield; filter the stray signal to obtain a harmonic signal; detect the energy of the harmonic signal; and determine that the electronic device is present when the energy of the harmonic signal exceeds a threshold Radiation spurious emission anomalies.

In a third aspect, the embodiment of the present application provides an electronic device, including the circuit board assembly described in the first aspect of the present invention.

In the embodiment of the present application, by setting the bracket on the main board, the bracket is provided with a signal processing circuit that can receive the stray signal leaked from the shield, and the signal processing circuit can filter the stray signal to obtain the harmonic signal, and send the harmonic signal to the signal detection circuit on the motherboard, the signal detection circuit detects the energy of the received harmonic signal, and when the energy of the harmonic signal exceeds the threshold, it is determined that the electronic device has an abnormal radiation spurious emission. After the equipment is produced, it is also possible to detect in real time whether the electronic equipment has abnormal radiation spurious emissions.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and understandable from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is a schematic diagram of a circuit board assembly in an embodiment of the present invention;

Fig. 2 is the schematic diagram of another kind of circuit board assembly in the embodiment of the present invention;

3 is a schematic diagram of a signal processing circuit in an embodiment of the present invention;

Fig. 4 is the schematic diagram of microstrip bandpass filter in the embodiment of the present invention;

FIG. 5 is a schematic diagram of another circuit board assembly in an embodiment of the present invention.

Reference signs:

100-mainboard; 101-third microstrip antenna; 102-transceiver; 200-shielding cover; 201-opening; 300-bracket; 301-first microstrip antenna; 302-microstrip bandpass filter; Two microstrip antennas.

Detailed ways

Embodiments of the present invention will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

The features of the terms "first" and "second" in the description and claims of the present application may explicitly or implicitly include one or more of these features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial", The orientation or positional relationship indicated by "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or element Must be in a particular orientation, be constructed in a particular orientation, and operate in a particular orientation, and therefore should not be construed as limiting the invention.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

The following describes a circuit board assembly, a radiation spurious emission abnormality detection method and an electronic device according to an embodiment of the present application with reference to FIGS. 1 to 5 .

According to one embodiment of the present invention, a circuit board assembly is provided. As shown in FIG. 1 , the circuit board assembly includes: a main board 100 on which a signal detection circuit is arranged. The shielding case 200 is disposed above the main board 100 and connected to the main board 100 , and a cavity is formed between the shielding case 200 and the main board 100 . The bracket 300 is arranged above the shielding cover 200 and connected to the main board 100 , the bracket 300 is provided with a signal processing circuit, and the signal processing circuit is used to receive stray signals leaked from the shielding cover 200 and performing filtering processing on the stray signal to obtain a harmonic signal, and sending the harmonic signal to the signal detection circuit. The signal detection circuit is used to receive the harmonic signal, detect the energy of the harmonic signal, and determine that the electronic device has abnormal radiation spurious emission when the energy of the harmonic signal exceeds a threshold.

The bracket 300 can be clamped on the main board 100 through a buckle structure, and the bracket 300 can also be fixed on the main board 100 by screws. Other connection methods can also be used between the bracket 300 and the main board 100. In this embodiment, the connection mode between the bracket and the main board No limit. There may be a gap between the bracket 300 and the shielding cover 200, and there may be a gap between the bracket 300 and the main board 100, and the size of the gap may be set according to actual requirements.

The shielding case 200 can be welded on the main board 100 . If the soldering between the shielding case 200 and the main board 100 is weak, stray signals may leak from the shielding case 200 . The signal processing circuit on the bracket 300 will receive stray signals. The signal processing circuit filters the stray signals to obtain harmonic signals. The signal processing circuit sends the harmonic signal to the signal detection circuit on the main board 100, and detects the energy of the harmonic signal through the signal detection circuit on the main board 100. If the energy of the harmonic signal exceeds a threshold value, it means that the electronic device has radiated spurious emissions. abnormal. After detecting abnormal radiation spurious emission of electronic equipment, the detection result can be reported to the manufacturer of the electronic equipment, which is convenient for the manufacturer to recycle and reduce the defective products on the market.

According to the circuit board assembly of the embodiment of the present invention, by setting the bracket on the main board, the bracket is provided with a signal processing circuit that can be used to receive the stray signal leaked from the shield, and the signal processing circuit can filter the stray signal to obtain Harmonic signal, and send the harmonic signal to the signal detection circuit on the main board, the signal detection circuit detects the energy of the received harmonic signal, and when the energy of the harmonic signal exceeds the threshold, it is determined that the electronic device has an abnormal radiation spurious emission, After the electronic equipment is produced, it is also possible to detect in real time whether the electronic equipment has abnormal radiation spurious emission.

Optionally, as shown in FIG. 2 , the shielding case 200 has an opening 201, and the signal processing circuit includes: a first microstrip antenna 301 disposed above the opening 201 of the shielding case 200 or at the edge of the shielding case 200 place, for receiving the spurious signal; microstrip bandpass filter 302, the first end of the microstrip bandpass filter 302 is connected to the first microstrip antenna 301, for filtering the leakage signal The signal at the fundamental frequency is output as a harmonic signal; the second microstrip antenna 303 is connected to the second end of the microstrip bandpass filter 302, and is used to transmit the harmonic signal to the signal detection circuit .

The shielding case 200 has an opening 201 , and a first microstrip antenna 301 is disposed on the support 300 at a position opposite to the opening 201 . The stray signal will leak out from the opening 201 on the shielding cover 200, and the first microstrip antenna 301 is arranged above the opening 201, which can facilitate the first microstrip antenna 301 to receive the stray signal.

Stray signals may also leak from the edge of the shield 200, and the first microstrip antenna 301 can also be arranged at the edge of the shield 200, so that the first microstrip antenna 301 can receive the stray signal leaked from the edge of the shield 200. Signal. In order to ensure that stray signals leaked from any position of the shielding case 200 can be received, a first microstrip antenna 301 can be provided above the opening 201 of the shielding case 200 and at the edge of the shielding case 200 .

As shown in FIG. 3 , the first end of the microstrip bandpass filter 302 is connected to the first microstrip antenna 301 through a microstrip line. The second end of the microstrip bandpass filter 302 is connected to the second microstrip antenna 302 through a microstrip line. After the first microstrip antenna 301 receives the spurious signal, the spurious signal is transmitted to the microstrip bandpass filter 302 through the microstrip line. The microstrip bandpass filter 302 filters the spurious signals to obtain harmonic signals, and transmits the harmonic signals to the second microstrip antenna 303 through the microstrip line. The second microstrip antenna 303 sends the harmonic signal to the signal detection circuit on the main board 100 .

In one example, as shown in FIG. 3 , the microstrip bandpass filter 302 is a fifth-order Chebyshev hairpin bandpass filter. The microstrip bandpass filter 302 includes five hairpin resonators, and the hairpin resonators are obtained by converting the half-wavelength stepped impedance resonator coupling structure into a U-shape. The performance of the microstrip bandpass filter 302 is determined by the structural parameters of each hairpin resonator. As shown in Fig. 4, the arm length of the hairpin resonator is L, the spacing of the hairpin resonators is S, the line width of the hairpin resonator is W, and the tap position is t. By adjusting the structural size of the hairpin bandpass filter, the frequency response of the hairpin bandpass filter can be adjusted. The formula for calculating the arm length L of a hairpin resonator is as follows:

Among them, h is the thickness of the dielectric plate of the microstrip structure, ε _r is the relative permittivity of the medium, and λ ₀ is the free-space propagation wavelength at the center frequency point of the filter. The calculation formula of the tap position t is as follows:

Among them, R is the characteristic impedance of the tap line, Z0 is the characteristic impedance of the hairpin resonator, and Q is the external coupling coefficient of the hairpin resonator.

In this embodiment, by arranging the first microstrip antenna above the opening of the shielding cover, the first microstrip antenna can more easily receive the stray signal leaked from the opening of the shielding cover, and improve the detection of abnormal radiation spurious emission of electronic equipment precision.

Optionally, as shown in FIG. 5 , the signal detection circuit includes: a third microstrip antenna 101, arranged on the motherboard 100 at a position opposite to the second microstrip antenna 303, and the third microstrip antenna The antenna 101 is outside the shielding case 200 and used to receive the harmonic signal sent by the second microstrip antenna 303 . The transceiver 102 is connected to the third microstrip antenna 101 and is configured to detect the energy of the harmonic signal, and determine that the electronic device has abnormal radiation spurious emission when the energy of the harmonic signal exceeds a threshold.

A third microstrip antenna 101 and a transceiver 102 are provided on the main board 100 . The third microstrip antenna 101 is disposed on the main board 100 opposite to the second microstrip antenna 303 . Specifically, the third microstrip antenna 101 may be disposed below the second microstrip antenna 303 . The transceiver 102 can be arranged at any position on the motherboard 100 .

The third microstrip antenna 101 can receive the harmonic signal sent by the second microstrip antenna 303 . The third microstrip antenna 101 is connected with the transceiver 102 through the microstrip line, the third microstrip antenna 101 can send the received harmonic signal to the transceiver 102 through the microstrip line, and detect the energy of the harmonic signal by the transceiver 102 . If it is detected that the energy of the harmonic signal exceeds the threshold, it is determined that the electronic device has abnormal radiation spurious emission.

In this embodiment, by arranging the third microstrip antenna on the main board at a position opposite to the second microstrip antenna, it is convenient for the third microstrip antenna to receive the harmonic signal sent by the second microstrip antenna.

Optionally, as shown in FIG. 5 , the transceiver 102 is disposed in the cavity, and the transceiver 102 is connected to the third microstrip antenna 101 through a microstrip line.

The transceiver 102 is disposed in the cavity formed by the shielding case 200 and the motherboard 100 , and the transceiver 102 is under the shielding case 200 . There is a receiver circuit in the transceiver 102, which can amplify, mix, filter and detect the harmonic signal, so as to obtain the frequency and energy information of the harmonic signal, and then judge whether the electronic device has abnormal radiation spurious emission.

The transceiver generates radio frequency signals when it is working. In this embodiment, the transceiver is placed in the cavity formed by the shielding cover and the main board to shield the radio frequency interference of the transceiver and allow the transceiver to work normally.

Optionally, the microstrip bandpass filter is any one of a hairpin bandpass filter, an interdigitated bandpass filter, and a SIR (Stepped Impedance Resonators, stepped impedance resonator) parallel coupled bandpass filter .

Optionally, the shielding case 200 has a plurality of openings 201 , and the first microstrip antenna 301 is provided at a position corresponding to each opening 201 on the bracket 300 .

There may be a plurality of openings 201 on the shielding case 200 , and when stray leakage occurs, stray signals may leak out from the plurality of openings 201 of the shielding case 200 . A first microstrip antenna 301 is provided at a position corresponding to each opening 201 on the bracket 300 , and the first microstrip antenna 301 can receive the stray signal leaked from the corresponding opening 201 . For example, if four openings 201 are provided on the shielding case 200 , then four first microstrip antennas 301 are provided on the bracket 300 . Each first microstrip antenna 301 is connected to the first end of the microstrip bandpass filter.

In this embodiment, when the shielding cover has multiple openings, a first microstrip antenna corresponding to each opening can be provided to receive stray signals leaking from any opening, avoiding omissions, and ensuring that all signals can be received. spurious signals, improve detection accuracy.

Optionally, the first microstrip antenna 301 is disposed on the support 300 at a position corresponding to the edge of the shielding case 200 .

Spurious signals may also leak from the edges of the shield 200 . The edge of the shielding case 200 refers to the connection between the shielding case 200 and the main board 100 . A first microstrip antenna 301 is provided at the edge of the shielding case 200, and the first microstrip antenna 301 can receive stray signals leaked from the edge of the shielding case 200, further improving detection accuracy.

Optionally, the signal processing circuit can be implemented in any of the following ways: microstrip structure, laser direct structuring (Laser-Direct-structuring, LDS), liquid crystal polymer (Liquid Crystal Polymer, LCP), flexible circuit board (Flexible Printed Circuit, FPC). The signal processing circuit is implemented by using a flexible circuit board. The material of the flexible circuit board is relatively soft, so that the circuit board components can be bent at will, which can adapt to the internal space of the electronic device and improve the utilization rate of the internal space of the electronic device. The antenna can be formed by chemical plating on the circuit board assembly by laser direct forming technology. Signal processing circuits can also be implemented using liquid crystal polymers.

This embodiment introduces a method for detecting abnormality of stray radiation emission, which is applied to the circuit board assembly described in any embodiment of the present invention, and the method includes steps 101-104.

Step 101: Receive the stray signal leaked from the shield.

The stray signal leaked from the shield is received by the first microstrip antenna on the bracket. This can be a stray signal leaking from any opening in the shield, or a spurious signal leaking from the edge of the shield.

Step 102: Filtering the stray signal to obtain a harmonic signal.

After the first microstrip antenna receives the spurious signal, the first microstrip antenna sends the spurious signal to the microstrip bandpass filter. The microstrip bandpass filter performs filtering processing on the spurious signal, and filters out the signal of the fundamental frequency in the spurious signal to obtain the harmonic signal.

Step 103: Detect the energy of the harmonic signal.

After filtering the spurious signals, the microstrip bandpass filter sends the harmonic signals to the second microstrip antenna. Under the joint action of the second microstrip antenna and the third microstrip antenna, the third microstrip antenna receives the harmonic signal. The third microstrip antenna sends the harmonic signal to the transceiver, and the energy of the harmonic signal is detected by the transceiver.

Step 104: When the energy of the harmonic signal exceeds a threshold, determine that the electronic device has an abnormal radiation spurious emission.

According to the detection result of the harmonic signal, it is judged whether the electronic equipment has abnormal radiation spurious emission. If the energy of the harmonic signal exceeds the threshold, the electronic device is considered to have abnormal radiation spurious emissions.

In this embodiment, by receiving the stray signal leaked from the shielding cover, filtering the stray signal to obtain the harmonic signal, detecting the energy of the harmonic signal, and judging whether the electronic device has abnormal radiation spurious emission according to the detection result, it can detect in real time Whether the electronic equipment has abnormal radiation spurious emission.

This embodiment introduces an electronic device, which has the circuit board assembly as described in any one of the above embodiments, and can detect in real time whether the electronic device has abnormal radiation spurious emission.

In the description of this specification, references to the terms "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific examples," or "some examples" are intended to mean that the implementation A specific feature, structure, material, or characteristic described by an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes, modifications, substitutions and modifications can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the invention is defined by the claims and their equivalents.

Claims (10)

1. A circuit board assembly, comprising:

the main board is provided with a signal detection circuit;

the shielding cover is arranged above the main board and connected with the main board, and a cavity is formed by enclosing the shielding cover and the main board;

the bracket is arranged above the shielding cover and connected with the main board, a signal processing circuit is arranged on the bracket and is used for receiving stray signals leaked from the shielding cover, filtering the stray signals to obtain harmonic signals, and sending the harmonic signals to the signal detection circuit;

the signal detection circuit is used for receiving the harmonic signals, detecting the energy of the harmonic signals, and determining that the electronic equipment has radiation spurious emission abnormality when the energy of the harmonic signals exceeds a threshold value.

2. The circuit board assembly of claim 1, wherein the shield has an opening, the signal processing circuit comprising:

the first microstrip antenna is arranged above the opening of the shielding case or at the edge of the shielding case and is used for receiving the stray signals;

the first end of the microstrip band-pass filter is connected with the first microstrip antenna and is used for filtering signals with fundamental wave frequency in the leakage signals and outputting harmonic signals;

and the second microstrip antenna is connected with the second end of the microstrip band-pass filter and is used for transmitting the harmonic signals to the signal detection circuit.

3. The circuit board assembly of claim 2, wherein the signal detection circuit comprises:

the third microstrip antenna is arranged on the main board at a position opposite to the second microstrip antenna, and is arranged on the outer side of the shielding cover and used for receiving the harmonic signals sent by the second microstrip antenna;

and the transceiver is connected with the third microstrip antenna and is used for detecting the energy of the harmonic signal, and determining that the electronic equipment has abnormal radiation spurious emission when the energy of the harmonic signal exceeds a threshold value.

4. A circuit board assembly according to claim 3, wherein the transceiver is disposed within the cavity, the transceiver being connected to the third microstrip antenna by a microstrip line.

5. The circuit board assembly of claim 2, wherein the microstrip bandpass filter is any one of a hairpin bandpass filter, an interdigital bandpass filter, and an SIR parallel coupled bandpass filter.

6. The circuit board assembly of claim 2, wherein the shield has a plurality of openings, and the first microstrip antenna is provided on the support at a location corresponding to each of the openings.

7. The circuit board assembly of claim 2, wherein the first microstrip antenna is disposed on the support at a location corresponding to an edge of the shield.

8. The circuit board assembly of claim 1, wherein the signal processing circuit is implemented by any one of: microstrip structure, laser direct structuring technology, liquid crystal polymer, flexible circuit board.

9. A method for detecting radiation spurious emissions anomalies, wherein the method is applied to the circuit board assembly of any one of claims 1 to 8, the method comprising:

receiving stray signals leaking from the shield;

filtering the spurious signals to obtain harmonic signals;

detecting energy of the harmonic signal;

and under the condition that the energy of the harmonic signal exceeds a threshold value, determining that the electronic equipment has radiation spurious emission abnormality.

10. An electronic device having the circuit board assembly of any one of claims 1-8.

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