CN114206005A - Method and system for reducing absorption or emission power of printed circuit board circuit - Google Patents
Method and system for reducing absorption or emission power of printed circuit board circuit Download PDFInfo
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- CN114206005A CN114206005A CN202111504091.9A CN202111504091A CN114206005A CN 114206005 A CN114206005 A CN 114206005A CN 202111504091 A CN202111504091 A CN 202111504091A CN 114206005 A CN114206005 A CN 114206005A
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- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000010521 absorption reaction Methods 0.000 title claims abstract description 11
- 230000005670 electromagnetic radiation Effects 0.000 claims abstract description 21
- 238000009826 distribution Methods 0.000 claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 claims abstract description 11
- 239000000523 sample Substances 0.000 claims description 34
- 230000005855 radiation Effects 0.000 claims description 28
- 238000005259 measurement Methods 0.000 claims description 17
- 238000012545 processing Methods 0.000 claims description 7
- 238000013528 artificial neural network Methods 0.000 claims description 6
- 238000004458 analytical method Methods 0.000 claims description 4
- 239000002131 composite material Substances 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 3
- 238000005457 optimization Methods 0.000 claims description 3
- 238000007781 pre-processing Methods 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012549 training Methods 0.000 description 1
Images
Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/0005—Apparatus or processes for manufacturing printed circuits for designing circuits by computer
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0213—Electrical arrangements not otherwise provided for
- H05K1/0216—Reduction of cross-talk, noise or electromagnetic interference
- H05K1/0218—Reduction of cross-talk, noise or electromagnetic interference by printed shielding conductors, ground planes or power plane
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0213—Electrical arrangements not otherwise provided for
- H05K1/0237—High frequency adaptations
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0213—Electrical arrangements not otherwise provided for
- H05K1/0237—High frequency adaptations
- H05K1/024—Dielectric details, e.g. changing the dielectric material around a transmission line
Abstract
The invention relates to the field of printed circuits, in particular to a method and a system for reducing the absorption or emission power of a printed circuit board circuit, which comprises the steps of scanning the circuit board to obtain a data image and the size of each element; optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board; measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area; and adding a shielding layer at the strong interference area. Through the mode, the emission frequency of the element on the circuit board can be reduced firstly, so that the electromagnetic interference to the adjacent element can be reduced firstly, then the areas with strong interference can be found by measuring the electromagnetic distribution condition on the improved circuit board, and then the shielding layers can be respectively installed in the areas, so that the anti-electromagnetic interference capability is further improved.
Description
Technical Field
The present invention relates to the field of printed circuits, and more particularly, to a method and system for reducing the power absorbed or transmitted by a printed circuit board.
Background
With the development of electronic science and technology, the electromagnetic environment of various electronic devices becomes worse and worse, and the printed circuit board circuit is more and more easily interfered by the external electromagnetic environment. This requires increased interference resistance of the printed circuit board circuitry.
The existing circuit board has poor anti-interference performance, and the use stability of the circuit board is reduced.
Disclosure of Invention
The invention aims to provide a method and a system for reducing the absorption or emission power of a printed circuit board circuit, aiming at improving the anti-interference capability of the circuit board and ensuring that the circuit board runs more stably.
In order to achieve the above object, in a first aspect, the present invention provides a method for reducing the absorption or emission power of a circuit on a printed circuit board, comprising scanning the circuit board to obtain a data image and the size of each element;
optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board;
measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
and adding a shielding layer at the strong interference area.
The method for scanning the circuit board to obtain the data image and the size of each element comprises the following specific steps:
photographing the circuit board;
preprocessing the photo;
identifying the electronic element by the preprocessed image based on an identification model obtained by a deep neural network;
and measuring and calibrating the electronic components to obtain the size of each electronic component.
The method comprises the following specific steps of optimizing parameters of high-frequency elements on the circuit board and manufacturing the low-power circuit board:
acquiring a high-frequency electronic element on a circuit board;
reducing the geometric size of the high-frequency electronic element;
increasing the dielectric constant of the circuit board dielectric layer;
and manufacturing the low-power circuit board.
The method comprises the following specific steps of measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area:
placing the first probe and the second probe on a low-power circuit board for measurement to obtain a high-frequency circuit radiation electromagnetic interference time domain signal;
processing and separating a high-frequency circuit radiation electromagnetic interference time domain signal into an independent common mode radiation signal and a differential mode radiation signal by using a blind signal analysis method;
and reconstructing each independent electromagnetic radiation source forming the electromagnetic interference composite field to obtain a strong interference area.
When the first probe and the second probe are placed on the low-power circuit board for measurement, the distances between the first probe and the second probe and the circuit plane are equal.
The specific steps of adding the shielding layer at the strong interference area are as follows:
dividing the strong interference area to obtain a plurality of sub-interference areas;
designing a shielding layer based on the sub-interference region;
the shield is assembled to the low power circuit board.
In a second aspect, the present invention also provides a system for reducing the power absorbed or transmitted by a printed circuit board circuit, comprising: a scanning component, an optimizing component, an electromagnetic radiation intensity detecting component and an assembling component,
the scanning assembly is used for scanning the circuit board to generate a data image and the size of each element;
the optimization component is used for optimizing parameters of the high-frequency element on the circuit board;
the electromagnetic radiation intensity detection assembly is used for measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
the assembly component is used for adding a shielding layer at a strong interference area.
The invention relates to a method and a system for reducing the absorption or emission power of a printed circuit board circuit, which comprises the steps of scanning the circuit board to obtain a data image and the size of each element; optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board; measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area; and adding a shielding layer at the strong interference area. Through the mode, the emission frequency of the element on the circuit board can be reduced firstly, so that the electromagnetic interference to the adjacent element can be reduced firstly, then the areas with strong interference can be found by measuring the electromagnetic distribution condition on the improved circuit board, and then the shielding layers can be respectively installed in the areas, so that the anti-electromagnetic interference capability is further improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a flow chart of a method of reducing the absorbed or transmitted power of printed circuit board circuitry in accordance with the present invention.
Fig. 2 is a flow chart of the present invention for scanning a circuit board to obtain a data image and dimensions of various components.
FIG. 3 is a flow chart of the present invention for optimizing parameters of high frequency components on a circuit board and fabricating a low power circuit board.
Fig. 4 is a flow chart of measuring the electromagnetic radiation field intensity distribution of the low-power circuit board to obtain the strong interference area according to the present invention.
Fig. 5 is a flow chart of the present invention for adding a shielding layer at a strong interference region.
FIG. 6 is a flow chart of the present invention for recognizing electronic components based on a recognition model obtained by a deep neural network from a preprocessed image.
Fig. 7 is a flow chart of the present invention for measuring and calibrating electronic components to obtain the dimensions of each electronic component.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
Referring to fig. 1 to 7, in a first aspect, the present invention provides a method for reducing absorption or emission power of a circuit of a printed circuit board, including:
s101, scanning the circuit board to obtain a data image and the size of each element;
the method comprises the following specific steps:
s201, shooting the circuit board;
and a high-precision camera is adopted to photograph the circuit board, preferably to photograph in a forward direction so as to reduce distortion generated during photographing, thereby improving the precision of post image processing.
S202, preprocessing the picture;
and processing the photographed picture, wherein the processing process comprises graying the picture, denoising points and the like, so that the processed picture can be conveniently identified at a later stage.
S203, recognizing the electronic element by the preprocessed image based on a recognition model obtained by a deep neural network;
in order to facilitate automatic processing, the electronic elements can be automatically identified by adopting a computer vision technology, and the shapes of the electronic elements on the circuit board are regular, so that the electronic elements can be conveniently identified.
The method comprises the following specific steps:
s601, inputting electronic elements in a sample library into a deep neural network for training to obtain a recognition model;
the sample library stores a database of existing component pictures, so that the deep neural network can be trained to obtain a corresponding recognition model based on the pictures.
S602, the preprocessed image is identified through an identification model.
And identifying the image processed by the steps so as to obtain the corresponding electronic component type.
S204, the electronic components are measured and calibrated to obtain the size of each electronic component.
The method comprises the following specific steps:
s701, measuring the electronic element;
the electronic component dimensions in the image are measured.
S702 calibrates the electronic component based on the photographing parameter.
When shooting, the position of the camera can influence the measured accurate value, so that the shooting parameters of the camera can be read to correct the measured value.
S102, optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board;
the method comprises the following specific steps:
s301, acquiring a high-frequency electronic element on a circuit board;
the high-frequency electronic components are mainly radio-frequency components, such as antennas.
S302, reducing the geometric size of the high-frequency electronic element;
the thickness and width of the tracks can be generally deteriorated by reducing the height of the microstrip line of the antenna.
S303, increasing the dielectric constant of the circuit board dielectric layer;
the dielectric layer is a plate for keeping insulativity between the circuit and each layer, is commonly called as a base material, increases dielectric constant, can enhance the capability of the plate for keeping charges, and can effectively reduce the absorption or emission power of the printed circuit board circuit.
S304, manufacturing the low-power circuit board.
The improved electronic component is re-assembled with other components, so that a low-power circuit board can be obtained.
S103, measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
the method comprises the following specific steps:
s401, placing a first probe and a second probe on a low-power circuit board for measurement to obtain a high-frequency circuit radiation electromagnetic interference time domain signal;
and respectively connecting a first probe and a second probe with a first channel and a second channel of the dual-trace oscilloscope, wherein the first probe and the second probe are of the same type, and the two probes are both electric field probes or magnetic field probes.
Respectively placing a first probe and a second probe near a high-frequency circuit for n times of measurement, and obtaining a high-frequency circuit radiation EMI time domain signal from a dual-trace oscilloscope; the number of times n of measurement is related to the number of electromagnetic interference sources radiated in the high-frequency circuit to be measured, and for the high-frequency circuit, n is 4 or n is 5, and the distances between the two probes and the circuit plane are equal during each measurement.
S402, processing and separating the high-frequency circuit radiation electromagnetic interference time domain signal into an independent common mode radiation signal and a differential mode radiation signal by using a blind signal analysis method;
the blind signal analysis method refers to blind signal separation, which refers to the separation of a plurality of observed mixed signals into an unobserved original signal. The mixed signal is typically observed from the outputs of multiple sensors, and the output signals of the sensors are independent (linearly uncorrelated).
Comparing the measurement results, and if the measurement result of the first probe of a certain radiation interference source is greater than the measurement result of the second probe, indicating that the radiation characteristic of the radiation interference source is mainly common-mode radiation; if the measurement result of the first probe of a certain radiation interference source is greater than the measurement result of the second probe, the radiation characteristic of the radiation interference source is mainly differential mode radiation, if the measurement result of the first probe of the certain radiation interference source is not greatly different from the measurement result of the second probe of the certain radiation interference source and is more prominent, the radiation source is not a common mode source but a differential mode source, and if the measurement result of the first probe and the measurement result of the second probe of the certain radiation interference source are obviously smaller, the radiation interference source does not belong to the radiation source.
S403, reconstructing each independent electromagnetic radiation source forming the radiation electromagnetic interference composite field to obtain a strong interference area.
The reconstruction may result in independent interferers, and based on these independent interferers and the set interference threshold, the area exceeding the interference threshold may be set as a strong interference area.
S104, adding a shielding layer at a strong interference area.
The method comprises the following specific steps:
s501, dividing the strong interference area to obtain a plurality of sub-interference areas;
for better design and installation of the shielding, the regions of strong interference can be segmented.
S502, designing a shielding layer based on the sub-interference region;
a shielding layer made of a metal sheet having conductivity is provided on the basis of each of the divided sub-interference regions.
S503 assembles the shield layer onto the low power circuit board.
The shield layer may be mounted to the low power circuit board by means of adhesive.
One of the invention
In a second aspect, the present invention also provides a system for reducing the power absorbed or transmitted by a printed circuit board circuit, comprising: a scanning component, an optimizing component, an electromagnetic radiation intensity detecting component and an assembling component,
the scanning assembly is used for scanning the circuit board to generate a data image and the size of each element;
the optimization component is used for optimizing parameters of the high-frequency element on the circuit board;
the electromagnetic radiation intensity detection assembly is used for measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
the assembly component is used for adding a shielding layer at a strong interference area.
The invention relates to a method and a system for reducing the absorption or emission power of a printed circuit board circuit, which comprises the steps of scanning the circuit board to obtain a data image and the size of each element; optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board; measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area; and adding a shielding layer at the strong interference area. Through the mode, the emission frequency of the element on the circuit board can be reduced firstly, so that the electromagnetic interference to the adjacent element can be reduced firstly, then the areas with strong interference can be found by measuring the electromagnetic distribution condition on the improved circuit board, and then the shielding layers can be respectively installed in the areas, so that the anti-electromagnetic interference capability is further improved.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (7)
1. A method for reducing the absorbed or transmitted power of printed circuit board circuit,
the method comprises the following steps: scanning the circuit board to obtain a data image and the size of each element;
optimizing parameters of high-frequency elements on the circuit board, and manufacturing a low-power circuit board;
measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
and adding a shielding layer at the strong interference area.
2. The method of reducing power absorbed or transmitted by a printed circuit board circuit of claim 1,
the specific steps of scanning the circuit board to obtain the data image and the size of each element are as follows:
photographing the circuit board;
preprocessing the photo;
identifying the electronic element by the preprocessed image based on an identification model obtained by a deep neural network;
and measuring and calibrating the electronic components to obtain the size of each electronic component.
3. The method of reducing power absorbed or transmitted by a printed circuit board circuit of claim 1,
the specific steps of optimizing the parameters of the high-frequency element on the circuit board and manufacturing the low-power circuit board are as follows:
acquiring a high-frequency electronic element on a circuit board;
reducing the geometric size of the high-frequency electronic element;
increasing the dielectric constant of the circuit board dielectric layer;
and manufacturing the low-power circuit board.
4. The method of reducing power absorbed or transmitted by a printed circuit board circuit of claim 1,
the method for measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain the strong interference area comprises the following specific steps:
placing the first probe and the second probe on a low-power circuit board for measurement to obtain a high-frequency circuit radiation electromagnetic interference time domain signal;
processing and separating a high-frequency circuit radiation electromagnetic interference time domain signal into an independent common mode radiation signal and a differential mode radiation signal by using a blind signal analysis method;
and reconstructing each independent electromagnetic radiation source forming the electromagnetic interference composite field to obtain a strong interference area.
5. The method of reducing power absorbed or transmitted by a printed circuit board circuit of claim 4,
when the first probe and the second probe are placed on the low-power circuit board for measurement, the distances between the first probe and the second probe and the circuit plane are equal.
6. A method of reducing power absorbed or transmitted by printed circuit board circuitry as recited in claim 5,
the specific steps of adding the shielding layer at the strong interference area are as follows:
dividing the strong interference area to obtain a plurality of sub-interference areas;
designing a shielding layer based on the sub-interference region;
the shield is assembled to the low power circuit board.
7. A system for reducing the absorption or emission power of printed circuit board circuits, applied to the method for reducing the absorption or emission power of printed circuit board circuits as claimed in any one of claims 1 to 6,
the method comprises the following steps: a scanning component, an optimizing component, an electromagnetic radiation intensity detecting component and an assembling component,
the scanning assembly is used for scanning the circuit board to generate a data image and the size of each element;
the optimization component is used for optimizing parameters of the high-frequency element on the circuit board;
the electromagnetic radiation intensity detection assembly is used for measuring the electromagnetic radiation field intensity distribution condition of the low-power circuit board to obtain a strong interference area;
the assembly component is used for adding a shielding layer at a strong interference area.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111504091.9A CN114206005A (en) | 2021-12-10 | 2021-12-10 | Method and system for reducing absorption or emission power of printed circuit board circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111504091.9A CN114206005A (en) | 2021-12-10 | 2021-12-10 | Method and system for reducing absorption or emission power of printed circuit board circuit |
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| CN114206005A true CN114206005A (en) | 2022-03-18 |
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| CN202111504091.9A Pending CN114206005A (en) | 2021-12-10 | 2021-12-10 | Method and system for reducing absorption or emission power of printed circuit board circuit |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2682776Y (en) * | 2003-11-24 | 2005-03-02 | 神基科技股份有限公司 | Electromagnetic wave suppressing and shielding structure for circuit substrate interference source |
| CN101839949A (en) * | 2010-05-25 | 2010-09-22 | 东南大学 | High frequency circuit radiation electromagnetic inference analysis method |
| CN201590990U (en) * | 2009-09-28 | 2010-09-22 | 青岛海信移动通信技术股份有限公司 | Electromagnetic shielding cover and electronic device |
| CN110602873A (en) * | 2019-09-16 | 2019-12-20 | 西北核技术研究院 | Method for reducing absorption or emission power of printed circuit board circuit and prediction method |
| CN111353410A (en) * | 2020-02-25 | 2020-06-30 | 北京师范大学珠海分校 | Electromagnetic interference analysis method, device, equipment and storage medium |
| CN113159064A (en) * | 2021-04-06 | 2021-07-23 | 高书俊 | Method and device for detecting electronic element target based on simplified YOLOv3 circuit board |
-
2021
- 2021-12-10 CN CN202111504091.9A patent/CN114206005A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2682776Y (en) * | 2003-11-24 | 2005-03-02 | 神基科技股份有限公司 | Electromagnetic wave suppressing and shielding structure for circuit substrate interference source |
| CN201590990U (en) * | 2009-09-28 | 2010-09-22 | 青岛海信移动通信技术股份有限公司 | Electromagnetic shielding cover and electronic device |
| CN101839949A (en) * | 2010-05-25 | 2010-09-22 | 东南大学 | High frequency circuit radiation electromagnetic inference analysis method |
| CN110602873A (en) * | 2019-09-16 | 2019-12-20 | 西北核技术研究院 | Method for reducing absorption or emission power of printed circuit board circuit and prediction method |
| CN111353410A (en) * | 2020-02-25 | 2020-06-30 | 北京师范大学珠海分校 | Electromagnetic interference analysis method, device, equipment and storage medium |
| CN113159064A (en) * | 2021-04-06 | 2021-07-23 | 高书俊 | Method and device for detecting electronic element target based on simplified YOLOv3 circuit board |
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