CN112115671B - Circuit structure for improving electromagnetic radiation of processor clock signal end and forming method thereof - Google Patents
Circuit structure for improving electromagnetic radiation of processor clock signal end and forming method thereof Download PDFInfo
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- 230000005670 electromagnetic radiation Effects 0.000 title claims abstract description 78
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- 230000005672 electromagnetic field Effects 0.000 abstract description 14
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/30—Circuit design
- G06F30/39—Circuit design at the physical level
- G06F30/392—Floor-planning or layout, e.g. partitioning or placement
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2115/00—Details relating to the type of the circuit
- G06F2115/12—Printed circuit boards [PCB] or multi-chip modules [MCM]
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Abstract
The invention provides a circuit structure for improving electromagnetic radiation of a processor clock signal end and a forming method thereof, wherein the circuit structure for improving electromagnetic radiation of the processor clock signal end comprises a processor, the processor comprises at least one clock signal end, a functional module, a pulse width modulation signal port and an IO port, wherein the functional module is electrically connected with the clock signal end, and a circuit is electrically connected between the pulse width modulation signal port and the IO port to form at least one offset loop, so that electromagnetic radiation generated by the electrical connection between the clock signal end and the functional module is offset. The circuit structure for improving the electromagnetic radiation of the clock signal end of the processor can realize electromagnetic field cancellation by utilizing elements in the processor, thereby realizing the improvement of the electromagnetic radiation of the clock signal end of the processor and generating no extra electromagnetic radiation.
Description
Technical Field
The invention relates to the technical field of electromagnetic radiation, in particular to a circuit structure for improving electromagnetic radiation of a clock signal end of a processor.
Background
Along with the increasing popularity of electronic products, the requirement on the safety of the electronic products is higher, electromagnetic radiation is a focus of attention, and the electronic products are mainly inspected through EMC tests, wherein the EMC tests are also called electromagnetic compatibility EMC, refer to comprehensive evaluation of the electromagnetic field interference (EMI) and anti-interference capability (EMS) of the electronic products, are one of the most important indexes of the quality of the electronic products, and aim to detect the influence of the electromagnetic radiation generated by the electronic products on human bodies, public place power grids and other normally working electronic products. The electromagnetic compatibility is a subject for researching that under the conditions of limited space, time and frequency spectrum resources, various electric equipment can coexist in a broad sense, and the biological equipment does not cause degradation, and comprises two parts, namely electromagnetic interference and electromagnetic sensitivity, wherein the electromagnetic interference test is used for measuring the intensity of electromagnetic wave signals which are generated by the tested equipment in a normal working state and emitted outwards to reflect the interference of surrounding electronic equipment, and the electromagnetic sensitivity test is used for measuring the intensity of the tested equipment on the interference resistance of the electromagnetic disturbance.
The RE test in the EMC test of the PCB level of the electronic product is a very important parameter in the security test index of the circuit board, various international standards have strict requirements on the index, and because electromagnetic radiation often appears in a plurality of unpredictable frequency bands and can be reflected according to actual test conditions, the RE test is very easy to exceed standard, so that an electronic hardware engineer of each electronic product can possibly spend a lot of time and a lot of test cost to solve the problem.
The first problem to be solved is to accurately position the problem, and no correction is needed in the positioning process, so that the problem is knocked everywhere like a headless fly. Two means are provided for problem positioning, namely, intuitive judgment of an engineer is considered, and the judgment is required to be completely carried out by virtue of EMC experience accumulated by the engineer; and secondly, comparing and testing, and carrying out detailed positioning judgment on the problems by means of combination of instruments and EMC experience. In two general aspects, firstly, various power cables and signal cables connected with the machine equipment are detected and positioned through pulling and inserting, and then different rectifying measures are adopted according to phenomena; secondly, whether reasonable has great relation with structural design, the leakage of the shielding body can have great influence on the excessive RE radiation.
The conventional solutions to RE radiation are two kinds, namely, trying to find a radiation source, reducing radiation by modifying the electrical parameters of the circuit resistance, while reducing the problem of RE test exceeding, other problems, such as poor signal quality caused by the reduction of signal driving capability, are often introduced, and more experiments are required to demonstrate the stability of the method, because of the problem of RE test exceeding, many previous circuit stability experiments are repeated, and the time cost is increased.
In addition, a part of the signals are difficult to remove from the circuit because of the circuit structure itself, and in this case, it is common practice in the prior art to add a metal shielding frame to shield the generated electromagnetic radiation. However, this approach has inherent drawbacks, firstly, because of the addition of the metal shielding frame, the number of parts of the circuit structure itself and the volume of the circuit structure tend to be increased, which obviously limits the applicability to some small and miniature electronic products; in addition, this approach also adds relatively high cost due to the addition of the metal shield, which also affects cost control of the product and consumer acceptance.
As shown in fig. 1, a test picture of RE radiation in the prior art is shown. As shown in the figure, four points 1, 2, 3 and 4 in the figure are points with EMC exceeding standard, wherein the frequency of the 1 st point is 125MHz, the frequency of the 2 nd point is 375MHz, the frequency of the 3 rd point is 625MHz, the frequency of the 4 th point is 875MHz, the 125MHz is the clock source, the other 3 frequencies are 3,5 and 7 times of the frequency of the 125MHz respectively, and the line pressing condition also exists.
Disclosure of Invention
It is an advantage of the present invention to provide a circuit arrangement for improving electromagnetic radiation at a processor clock signal terminal that enables electromagnetic field cancellation using components within a processor, thereby enabling an improvement of electromagnetic radiation at a processor clock signal terminal.
One advantage of the present invention is to provide a circuit structure for improving electromagnetic radiation of a processor clock signal end, wherein the circuit structure for improving electromagnetic radiation of a processor clock signal end utilizes redundant PWM interface or IO interface resources of a processor chip, adds a 125M clock signal in a reverse way, and can cancel theoretical and actual phenomena according to electromagnetic fields, and uses at least 1 PCB wiring in opposite directions to digest the electromagnetic fields internally, thereby improving electromagnetic radiation of the processor clock signal end.
An advantage of the present invention is to provide a circuit structure for improving electromagnetic radiation at a clock signal end of a processor, wherein the circuit structure for improving electromagnetic radiation at a clock signal end of a processor is provided with cancellation loops on the basis of the structure of the existing processor, so that a part of lines of each cancellation loop run parallel to and opposite to lines of the original radiation, and cancellation of electromagnetic radiation in the circuit structure is realized.
One advantage of the present invention is to provide a circuit structure for improving electromagnetic radiation at a clock signal end of a processor, wherein the number of layers of a PCB where a part of lines of each cancellation loop are located is the same as the number of layers of a PCB where lines between the clock signal end of the processor and a functional module are located, so as to improve the cancellation effect on electromagnetic radiation.
It is an advantage of the present invention to provide a circuit structure for improving electromagnetic radiation at the clock signal end of a processor, wherein the remaining lines of each cancellation loop are located in the inner layer of the PCB board where they are located, thereby reducing the generation of additional electromagnetic radiation.
It is an advantage of the present invention to provide a circuit structure for improving electromagnetic radiation at a clock signal terminal of a processor, wherein an operating frequency of a Pulse Width Modulation (PWM) signal port of the processor is identical to an operating frequency of the clock signal terminal, so as to enhance an electromagnetic cancellation effect of the circuit structure for improving electromagnetic radiation at the clock signal terminal of the processor and reduce a probability of generating additional electromagnetic radiation by a cancellation loop.
Another advantage of the present invention is to provide a method for forming a circuit structure for improving electromagnetic radiation of a clock signal end of a processor, wherein the method for forming a circuit structure for improving electromagnetic radiation of a clock signal end of a processor is improved by using an existing structure of the processor, and self-cancellation of electromagnetic radiation generated by the processor in a working process is realized by using a right-hand screw theorem and the like, and the method is simple and has reliable effect.
Another advantage of the present invention is to provide a method for forming a circuit structure for improving electromagnetic radiation at a clock signal end of a processor, where the method for forming a circuit structure for improving electromagnetic radiation at a clock signal end of a processor can control current and operating frequency in a cancellation loop through software, so as to improve cancellation effect on generated electromagnetic radiation, and the method is simple to operate and wide in application range.
In order to achieve at least the above advantages, the present invention provides a circuit structure for improving electromagnetic radiation of a clock signal end of a processor, the circuit structure for improving electromagnetic radiation of a clock signal end of a processor includes a processor, the processor includes at least one clock signal end, a functional module, a pwm signal port and an IO port, wherein the functional module is electrically connected to the clock signal end, and a circuit is electrically connected between the pwm signal port and the IO port to form at least one cancellation loop, so as to cancel electromagnetic radiation generated by the electrical connection between the clock signal end and the functional module.
In some embodiments, the clock signal terminal is electrically connected to the functional module through a first connection circuit, and the cancellation loop includes at least one second connection circuit, where the second connection circuit is parallel to the first connection circuit and has an opposite current direction.
In some embodiments, the processor further comprises at least one PCB board, and the first connection line and the second connection line are both disposed on the PCB board.
In some embodiments, the first connection line and the second connection line are both disposed on a surface layer of the PCB board.
In some embodiments, the rest of the second connection lines in the cancellation loop are disposed on an inner layer of the PCB board.
In some embodiments, the clock signal terminal has an operating frequency of 25MHz or a multiple thereof.
In some of these embodiments, the operating frequency of the pwm signal port is consistent with the operating frequency of the clock signal port.
The invention further comprises a method for forming a circuit structure for improving electromagnetic radiation at a clock signal end of a processor, comprising the steps of:
1001: selecting at least one IO port and one pulse modulation width signal port which are idle on a processor, and electrically connecting the IO port and the pulse modulation width signal port through at least one line to form at least one offset loop; and
1002: The circuit comprises a processor, a counter circuit and a control circuit, wherein the processor is electrically connected between a clock signal end and a functional module on the processor to form a first connecting circuit; and
1003: The second connection line is adjusted to be opposite to the current direction of the first connection line.
Drawings
Fig. 1 is a schematic diagram of a test structure for electromagnetic compatibility exceeding of a clock signal end of a processor in the prior art.
Fig. 2 is a schematic diagram of an electromagnetic field direction structure of a radiation signal line generated in a first embodiment of a circuit structure for improving electromagnetic radiation at a clock signal end of a processor according to the present invention.
Fig. 3 is a schematic diagram of a circuit structure for improving electromagnetic radiation of a clock signal terminal of a processor according to a first embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a first embodiment of a circuit structure for improving electromagnetic radiation at a clock signal end of a processor according to the present invention.
Fig. 5 is a schematic diagram of electromagnetic compatibility test results of a circuit structure for improving electromagnetic radiation at a clock signal end of a processor according to the present invention.
Fig. 6 is a flow chart of a method for forming a circuit structure for improving electromagnetic radiation of a clock signal terminal of a processor according to the present invention.
Detailed Description
The following description is presented to enable one of ordinary skill in the art to make and use the invention. The preferred embodiments in the following description are by way of example only and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
It will be understood that the terms "a" and "an" should be interpreted as referring to "at least one" or "one or more," i.e., in one embodiment, the number of elements may be one, while in another embodiment, the number of elements may be plural, and the term "a" should not be interpreted as limiting the number.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the 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 are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.
As shown in fig. 2 to 5, the present invention mainly provides a circuit structure for improving electromagnetic radiation of a clock signal end 111 of a processor 11, wherein the circuit structure for improving electromagnetic radiation of the clock signal end 111 of the processor 11 includes a processor 11 and a functional module 112, and the processor 11 includes at least one clock signal end 111, a functional module 112, a pwm signal port 113 and an IO port 114, wherein the functional module 112 is electrically connected to the clock signal end 111, and a line 116 is electrically connected between the pwm signal port 113 and the IO port 114 to form at least one cancellation loop 115, so as to cancel electromagnetic radiation generated by the electrical connection between the clock signal end 111 and the functional module 112.
In detail, as shown in fig. 2 and 3, the plurality of pwm signal ports 113 of the processor 11 are used as output terminals, the plurality of idle IO ports 114 of the processor 11 are used as input terminals, and a plurality of lines are provided to connect the output terminals, the functional modules 112, and the input terminals, respectively, so as to form a plurality of cancellation loops 115.
As shown in fig. 3, a portion of the line trend of each cancellation loop 115 is parallel to the line trend between the clock signal terminal 111 of the processor 11 and the functional module 112, and the current trend of the cancellation loop 115 is opposite to the current trend in the line between the clock signal terminal 111 of the processor 11 and the functional module 112.
As shown in fig. 4 and 5, the arrangement is such that the theoretical and actual phenomena can be cancelled by each other according to the electromagnetic field, the idle pwm signal port 113 and the IO port 114 on the processor 11 are used to connect them to form the cancellation loop 115, and a part of the line direction of the cancellation loop 115 is parallel to the line direction between the clock signal terminal 111 of the processor 11 and the functional module 112, and then the current direction in the cancellation loop 115 is controlled by the processor 11, so that the current direction in the cancellation loop 115 is opposite to the current direction in the line between the clock signal terminal 111 of the processor 11 and the functional module 112.
Then, according to the right-hand spiral law, an electromagnetic field with opposite directions to the electromagnetic field between the clock signal end 111 and the functional module 112 is generated in the cancellation loop 115, and because the electromagnetic fields with opposite directions can cancel each other, the electromagnetic radiation of the clock signal end 111 can be reduced in an auxiliary manner on the basis of other problems of improving the radiation standard exceeding by adopting a metal shielding mechanism and the like, so that the problem of the radiation test standard exceeding is further improved, the electromagnetic compatibility test standard is achieved, and the quality level of electronic products is improved. As described above, compared with the structure for reducing electromagnetic radiation in the prior art, the circuit structure for improving the electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention is not only simple in structure, but also is a structure arranged according to the electromagnetic cancellation principle, so that the working effect is stable.
Preferably, in the first embodiment of the present invention, the processor 11 includes a PCB board, and a connection line between the clock signal end 111 of the processor 11 and the functional module 112 is a first connection line 117, and the first connection line 117 is disposed on the PCB board. Accordingly, each cancellation loop 115 includes a second connection line 1161, where the second connection line 1161 is a line parallel to the first connection line 117 and having an opposite current direction, and the number of layers of the PCB where the second connection line 1161 is located is the same as the number of layers of the PCB where the first connection line 117 is located between the clock signal end 111 of the processor 11 and the functional module 112.
Since the second connection line 1161 in the cancellation loop 115 is parallel to the first connection line 117 between the clock signal terminal 111 of the processor 11 and the functional module 112 and has opposite current directions, the provision of the second connection line 1161 in the cancellation loop 115 at the same layer position as the first connection line 117 between the clock signal section and the functional module 112 can improve the cancellation effect of the electromagnetic field.
Further, the first connection line 117 between the clock signal terminal 111 and the functional module 112 is disposed on the surface layer of the PCB board, so as to reduce line consumption and ensure signal transmission quality. At the same time, however, the first connection line 117 is disposed on the surface layer of the PCB board, so that the electromagnetic radiation of the first connection line 117 is relatively high, and therefore, the second connection line 1161 in the cancellation loop 115 is also disposed on the surface layer of the PCB board, so as to maximally cancel the electromagnetic radiation generated by the first connection line 117.
The other connection lines 1162 except the second connection line 1161 in the cancellation loop 115 are disposed in the inner layer of the PCB board, so that electromagnetic radiation generated by the other connection lines 1162 in the cancellation loop 115 is blocked by the structure of the PCB board, thereby avoiding additional electromagnetic radiation generated by the circuit structure for improving electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention.
Preferably, in the circuit structure for improving electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention, since the working frequency of the clock signal end 111 in the practical electronic circuit is 25MHz, or a frequency multiplication of 25HMz, such as 125HMz, etc., only a software test is required to be passed, the working frequency of the corresponding pulse modulation width signal end in the processor 11 is set to be consistent with the working frequency, so that the electromagnetic field intensities generated by the two signals are equivalent, and the electromagnetic fields are more easily offset, and the probability of generating additional electromagnetic radiation by the offset loop 115 can be reduced.
Preferably, the second connection line 1161 in the cancellation loop 115 is disposed on both left and right sides of the second connection line 1161 between the clock signal terminal 111 and the functional module 112, so as to further improve the cancellation effect of the cancellation loop 115 on electromagnetic radiation.
In addition, a person skilled in the art may also adjust the specific position of the second connection line 1161 in the cancellation loop 115 according to the actual situation, for example, the second connection line 1161 in the cancellation loop 115 is disposed at a side of the first connection line 117 at intervals, which falls within the scope of the present invention. In other words, as long as the technical scheme which is the same as or similar to the present invention is adopted on the basis of the above disclosure of the present invention, the technical problem which is the same as or similar to the present invention is solved, and the technical effect which is the same as or similar to the present invention is achieved, which falls within the protection scope of the present invention, and the specific embodiments of the present invention are not limited thereto.
As described above, if the radiation in the radiation test is uniform narrow-band spike group noise, the calculator will interval how much the frequency difference is, which may be the fundamental frequency of its radiation source, and if the radiation test is single spike noise, it will be seen whether there is a frequency multiplication relationship between the spike noise and the clock frequency on the board, so this problem can be solved by the circuit structure for improving the electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention.
As shown in fig. 6, the present invention further provides a method for forming a circuit structure for improving electromagnetic radiation of the clock signal terminal 111 of the processor 11, the method for forming a circuit structure for improving electromagnetic radiation of the clock signal terminal 111 of the processor 11 comprising the steps of:
1001: selecting at least one IO port 114 and one pulse width signal port free on a processor 11, and electrically connecting between the IO port 114 and the pulse width signal port through at least one line 116 to form at least one cancellation loop 115; and
1002: A first connection line 117 is electrically connected between a clock signal terminal 111 and a functional module 112 on the processor 11, and a part of the circuits in the cancellation loop 115 are second connection lines 1161; and
1003: The second connection 1161 is adjusted to be opposite to the current direction of the first connection 117.
In step 1001, since the direction and position of the first connection line 117 between the clock signal terminal 111 and the functional module 112 on the processor 11 can be known in advance, several free IO ports 114 and pulse modulation width signal ports can be selected in design, so that a plurality of cancellation loops 115 can be designed.
In the step 1003, the second connection line 1161 is disposed on both sides of the first connection line 117 or is disposed at a side of the first connection line 117, so as to enhance the cancellation effect of the cancellation loop 115 on electromagnetic radiation.
In the first embodiment of the present invention, the second connection line 1161 is disposed in parallel with the position of the first connection line 117, thereby enhancing the canceling effect on electromagnetic radiation.
Preferably, in the step 1003, the operating frequency of the pwm signal port in the processor 11 is identical to the frequency of the clock signal port 111 in the processor 11, so that the electromagnetic field strength generated by the cancellation loop 115 is equivalent to the magnetic field strength generated between the clock signal port 111 and the functional module 112, so that cancellation is easier to achieve, and in addition, the probability that the cancellation loop 115 generates additional electromagnetic radiation is reduced.
Still further, in a first embodiment of the method for forming a circuit structure for improving electromagnetic radiation of a clock signal terminal 111 of a processor 11 according to the present invention, the clock signal terminal 111 has an operating frequency of 25MHz or a multiple of 25MHz, such as 125 MHz.
Preferably, in the step 1002, the layer number position of the second connection line 1161 on the PCB board of the processor 11 is consistent with the layer number position of the first connection line 117, so that the magnetic field generated by the second connection line 1161 can better cancel the magnetic field generated by the first connection line 117.
Further, the first connection line 117 and the second connection line 1161 are disposed on a surface layer of the PCB board in the processor 11, so as to reduce line signals of the first connection line 117 and ensure quality of signal transmission.
In addition, the specific positions of the first connection line 117 and the second connection line 1161, the operating frequency of the clock signal terminal 111, and the like may be determined by those skilled in the art according to actual situations. That is, as long as the technical scheme which is the same as or similar to the invention is adopted on the basis of the disclosure of the invention, the technical problem which is the same as or similar to the invention is solved, the technical effect which is the same as or similar to the invention is achieved, and the technical effect which is the same as or similar to the invention is all within the protection scope of the invention, and the specific embodiment of the invention is not limited by the invention.
In other words, in the method for forming the circuit structure for improving the electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention, the number of the cancellation loops 115 may be determined according to the actual requirement or according to the structure of the processor 11, for example, a plurality of the cancellation loops 115 are designed according to the requirement, so as to enhance the electromagnetic cancellation effect on the circuit structure for improving the electromagnetic radiation of the clock signal end 111 of the processor 11 according to the present invention.
Further, in the method for forming the circuit structure for improving electromagnetic radiation of the clock signal end 111 of the processor 11, after the PCB circuit board in the processor 11 is processed, an electromagnetic compatibility test (EMC) is performed on the PCB circuit board, so as to determine an out-of-standard point of a Radiation Emission (RE) test of the PCB circuit board and a range of the cancellation loop 115 where the out-of-standard point is located, so as to select one or more corresponding cancellation loops 115, and control a current and an operating frequency in the cancellation loop 115 by software allocation, so that the current and the operating frequency are consistent with the operating frequency of the clock signal end 111 in the processor 11, and observe radiation conditions in real time by using a far-field antenna until an optimal position of the cancellation loop 115 is found.
Finally, these parameters are stored in the system of the processor 11, and when each circuit generating a radiation emission signal works, the corresponding cancellation loop 115 is opened, so that the radiation emission test superscript point on the whole PCB board in the processor 11 is self-eliminated, and the electromagnetic radiation emission test of the clock signal terminal 111 meets the specification requirement in the working process of the PCB board in the processor 11.
It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are by way of example only and are not limiting. The objects of the present invention have been fully and effectively achieved. The functional and structural principles of the present invention have been shown and described in the examples and embodiments of the invention may be modified or practiced without departing from the principles described.
Claims (9)
1. The circuit structure for improving the electromagnetic radiation of the clock signal end of the processor is characterized by comprising a processor, wherein the processor comprises at least one clock signal end, a functional module, a pulse width modulation signal port and an IO port, the functional module is electrically connected with the clock signal end, and a circuit is electrically connected between the pulse width modulation signal port and the IO port to form at least one offset loop, so that the electromagnetic radiation generated by the electrical connection between the clock signal end and the functional module is offset;
the clock signal end is electrically connected with the functional module through a first connecting circuit, the counteracting loop locally comprises a second connecting circuit, the second connecting circuit is parallel to the first connecting circuit, and the processor controls the second connecting circuit to be opposite to the first connecting circuit in current direction.
2. The circuit structure for improving electromagnetic radiation of a clock signal terminal of a processor of claim 1, wherein the processor further comprises at least one PCB board, the first connection line and the second connection line being disposed on the PCB board.
3. The circuit structure for improving electromagnetic radiation of a processor clock signal terminal according to claim 2, wherein the first connection line and the second connection line are both disposed on a surface layer of the PCB board.
4. A circuit arrangement for improving electromagnetic radiation at a processor clock signal end according to claim 2 or 3, wherein the remaining connection lines of the cancellation loop, except for the second connection line, are arranged at an inner layer of the PCB board.
5. The circuit arrangement for improving electromagnetic radiation of a processor clock signal terminal of claim 4, wherein the clock signal terminal has an operating frequency of 25MHz or a multiple thereof.
6. The circuit arrangement for improving electromagnetic radiation at a clock signal terminal of a processor of claim 5, wherein an operating frequency of said pulse width modulated signal port is coincident with an operating frequency of said clock signal terminal.
7. A method of forming a circuit structure for improving electromagnetic radiation at a clock signal terminal of a processor, comprising the steps of:
1001: selecting at least one IO port and one pulse modulation width signal port which are idle on a processor, and electrically connecting the IO port and the pulse modulation width signal port through at least one line to form at least one offset loop; and
1002: The circuit comprises a processor, a counter circuit and a control circuit, wherein the processor is electrically connected between a clock signal end and a functional module on the processor to form a first connecting circuit; and
1003: The second connection line is adjusted to be opposite to the current direction of the first connection line.
8. The method for forming a circuit structure for improving electromagnetic radiation of a clock signal terminal of a processor as defined in claim 7, wherein the processor comprises a PCB, and the first connection line and the second connection line are respectively disposed on a surface layer of the PCB.
9. The method of claim 8, wherein an operating frequency of the pwm signal port in the processor is consistent with an operating frequency of the clock signal port.
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| CN212646773U (en) * | 2020-05-20 | 2021-03-02 | 纳瓦电子（上海）有限公司 | Circuit structure for improving electromagnetic radiation of clock signal end of processor |
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