CN103326794A - Adjusting method for home gateway communication terminal failing to pass radiated emission disturbance test - Google Patents
Adjusting method for home gateway communication terminal failing to pass radiated emission disturbance test Download PDFInfo
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- CN103326794A CN103326794A CN201310182230XA CN201310182230A CN103326794A CN 103326794 A CN103326794 A CN 103326794A CN 201310182230X A CN201310182230X A CN 201310182230XA CN 201310182230 A CN201310182230 A CN 201310182230A CN 103326794 A CN103326794 A CN 103326794A
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Abstract
The invention discloses an adjusting method for a home gateway communication terminal failing to pass a radiated emission disturbance test. Aiming at the radiation situation from the interior of a single plate, an adjusting scheme 1, an adjusting scheme 2 and an adjusting scheme 3 are adopted finally. Aiming at the radiation situation from an external signal port, an adjusting scheme 4, an adjusting scheme 5 and an adjusting scheme 6 are adopted finally. The adjusting method has the advantages that a frame and a structure of an equipment circuit of the home gateway communication terminal are not changed, the research and development speed of electronic equipment is increased fast so that the equipment can pass radiated emission disturbance as soon as possible, a passing rate of the radiated emission disturbance of the home gateway communication terminal equipment can be increased remarkably, and the adjusting method is simple and convenient to use and feasible, lowers the research and development cost of the home gateway communication terminal, and has good cost performance and promotional value.
Description
Technical field
The present invention relates to electronic equipment PCB technical field, the particularly filtering of electronic equipment, shielding, grounding technology field relate in particular to a kind of home gateway class communication terminal and fail to harass the method for adjustment of testing by radiation-emitting.
Background technology
Along with entering 21 century, the electromagnetic environment that goes from bad to worse is the matter of utmost importance that must solve, especially terminal called product class is led in family, large-scale outdoor communication product generally is metal shell, it is better that capability of electromagnetic shielding is done, and the non-metal shell that uses owing to cost control on this family gateway communication class product does not arrange Special grounding on the equipment, do not have shielded performance, can only lean on good principle diagram design and PCB design.
The main cause that home gateway class communication terminal device does not pass through in EMC emission test is the cabling situation of the various chip CLK on the veneer, there is the serious precipitous control situation of wearing layer and CLK rising edge, the filter design of Switching Power Supply, the layout of the filter design of network transformer and VOIP voice call particularly, these impacts are the reasons that causes finally not satisfying testing standard so that there is very serious problem in radiation-emitting.
Especially now reducing the cost use all is the chip of not considering very early the EMC design age a lot, and chip itself just brings out very large noise.Major part communication terminal company is the cheap network transformer of use cost all, removed the self coupling coil in the network transformer, used poor co-mode coil, the leakage inductances of some network transformers etc. are all very serious, the LAN mouth that makes through netting twine bring out common-mode noise very large, this is very serious radiation-emitting problem.
Summary of the invention
The object of the present invention is to provide a kind of home gateway class communication terminal to fail to harass the method for adjustment of testing by radiation-emitting, solve existing home gateway class communication terminal in the situation that do not increase equipment and cost, be not easy the problem by radiation-emitting harassing and wrecking experiment.
For addressing the above problem, the technical solution used in the present invention is:
A kind of home gateway class communication terminal fails to it is characterized in that: may further comprise the steps by the method for adjustment of radiation-emitting harassing and wrecking test:
Described adjustment scheme 1: the harmonic wave of the 125M frequency multiplication that PHY is produced is processed, check the filter design of PHY power supply, with analog power and the digital power isolation of magnetic bead with PHY, prevent the noise conduction, the power supply that PHY is used carries out filtering reinforcement, the electric capacity that uses 0.1UF-10UF not wait, the upper CLK that communicates by letter with MAC of PHY is adjusted processing, with RX_CLK, TX_CLK carries out resistors match, and resistance is between 49.9 ohm and 100 ohm;
Described adjustment scheme 2: the harmonic wave to the 480M frequency multiplication is processed, because 480M can determine to be caused by USB interface, directly check placement-and-routing's situation of USB, whether USB difference cabling is selected in suitable layer, avoid cutting a layer cabling, whether the differential lines that checks USB is walked in board edge to cause signal with reference to deficiency, and cabling is arranged on more than the interior 100mil of plate;
Described adjustment scheme 3: to frequency is suppressed by the envelope that power supply causes between 30M-100MHZ;
Described adjustment scheme 4: to the adjustment of RJ45 network interface BOB SIMITH circuit, remove the high-voltage capacitance of SIMITH circuit, adjust the resistance value of SIMITH circuit, perhaps whole removal SIMITH circuit, adjustment to network transformer centre cap filter capacitor, the network interface of 100M/1000M, tap are adjusted into the patch capacitor parallel connection of 1NF and 100NF, as far as possible near network transformer;
Described adjustment scheme 5: process the noise that is coupled to VOIP by the network interface partial noise;
Described adjustment scheme 6: refer to suppress the radiated noise that brings out on the 12V input line.
Further technical scheme is, so-called home gateway class communication terminal is tested the frequency that refers between 30-230MHZ in 10 meters darkrooms by the radiation-emitting harassing and wrecking, quasi-peak value is below 30db (uv/m), between the frequency of 230-1000MHZ, quasi-peak value is at 37db(uv/m) below and in AV value that 1GHZ-3GHZ records below 50db (uv/m), the PK value is below 70db (uv/m), and what the data communication device that records was like this crossed is CLASS B grade.
A kind of home gateway class communication terminal according to claim 1 fails to it is characterized in that by the method for adjustment of radiation-emitting harassing and wrecking test: in the described adjustment scheme 1, and described RX_CLK, the build-out resistor of the upper use of TX_CLK is 49.9 ohm-150 ohm.
A kind of home gateway class communication terminal according to claim 1 fails to it is characterized in that by the method for adjustment of radiation-emitting harassing and wrecking test: in the described adjustment scheme 4, and the filter capacitor of the parallel combination of a pair of 1NF of network transformer centre cap and 100NF.
The beneficial effect that adopts technique scheme to produce is:
1, do not change framework and the structure of home gateway class communication terminal device circuit.
2, improve fast the research and development speed of electronic equipment, make as soon as possible equipment by radiation-emitting harassing and wrecking test.
3, improve significantly the radiation-emitting of home gateway class communication terminal device and harass percent of pass.
4, easy, feasible, as to reduce home gateway class communication terminal R﹠D costs have preferably cost performance and promotional value.
Description of drawings
Fig. 1 is that a kind of home gateway class of the present invention communication terminal is failed the logic diagram of the embodiment of method of adjustment by radiation-emitting harassing and wrecking test.
Fig. 2 is the circuit diagram of adjustment scheme 1.
Fig. 3 is the circuit diagram of adjustment scheme 2.
Fig. 4 is the circuit diagram of adjustment scheme 3.
Fig. 5 is the circuit diagram of adjustment scheme 4.
Fig. 6 is the circuit diagram of adjustment scheme 5.
Fig. 7 is the circuit diagram of adjustment scheme 6.
Embodiment
In order to make purpose of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, is not intended to limit the present invention.
Radiation-emitting harassing and wrecking test is according to GB9254 " radio disturbance limit value and the method for measurement of Information Technology Equipment ", standard code device interior source frequency only proceeds to 1GHZ when being lower than the 108MHZ measurement, 108M-500MHZ then measures 2GHZ, home gateway class communication terminal inside sources frequency generally all greater than 108MHZ less than 500MHZ, so so-called home gateway class communication terminal is tested the frequency that refers between 30-230MHZ in 10 meters darkrooms by the radiation-emitting harassing and wrecking, quasi-peak value is below 30db (uv/m), between the frequency of 230-1000MHZ, quasi-peak value is at 37db(uv/m) below.1GHZ-3GHZ is below the AV value 50db (uv/m), and the PK value is below 70db (uv/m), and what pass through is CLASS B grade.
Fig. 1 shows a kind of home gateway class of the present invention communication terminal and fails an embodiment of the method for adjustment by radiation-emitting harassing and wrecking test:
A kind of home gateway class communication terminal fails to may further comprise the steps by the method for adjustment of radiation-emitting harassing and wrecking test:
As shown in Figure 2: step 1, when carrying out radiation-emitting harassing and wrecking test, whether the equipment of at first checking harasses the grade that requires by radiation-emitting, the standard code device interior source frequency of described radiation-emitting harassing and wrecking test only proceeds to 1GHZ when being lower than the 108MHZ measurement, 108M-500MHZ then measures 2GHZ, and home gateway communication terminal inside sources frequency is at 108MHZ-500MHZ;
As shown in Figure 2, described adjustment scheme 1: the harmonic wave of the 125M frequency multiplication that PHY is produced is processed, check the filter design of PHY power supply, with analog power and the digital power isolation of magnetic bead with PHY, prevent the noise conduction, the power supply that PHY is used carries out the filtering reinforcement, the electric capacity that uses 0.1UF-10UF not wait, preferred 0.1UF, 1UF, each 2 of 10UF electric capacity, the upper CLK that communicates by letter with MAC of PHY is adjusted processing, and with RX_CLK, TX_CLK carries out resistors match, resistance is between 49.9 ohm and 100 ohm, preferred 75 ohm the best can be adjusted to 150 ohm in the situation that do not affect signal integrity for indivedual poor planks, prevents that the CLK rising edge is too fast, the harmonic ratio that overshoot causes too greatly is abundanter, also can adjust the operating voltage of indivedual PHY chips, as can be under the normal work prerequisite of PHY, the voltage swing that suitable reduction PHY chip uses, reduce PHY internal work electric current, thereby reduced the upper external radiation of noise of CLK;
As shown in Figure 3, described adjustment scheme 2: the harmonic wave to the 480M frequency multiplication is processed, because 480M can determine to be caused by USB interface, directly check placement-and-routing's situation of USB, whether USB difference cabling is selected in suitable layer, avoid cutting a layer cabling, whether the differential lines that checks USB is walked in board edge to cause signal with reference to deficiency, cabling is arranged on more than the interior 100mil of plate, add the clock build-out resistor on the differential lines, part on the common mode inductance of reserving on the differential lines, the bag ground punching of differential lines has not evenly;
As shown in Figure 4, described adjustment scheme 3: to frequency is suppressed by the envelope that power supply causes between 30M-100MHZ, the magnetic bead size is preferably 100M, 600 ohm specification, the 12V input adds common mode inductance on veneer, adds several greater than the filter capacitor about 220UF; Turn 3.3V at 12V, the output of the voltage change-over switch chips such as 1.8V and input pin add magnetic bead;
As shown in Figure 5, described adjustment scheme 4: to the adjustment of RJ45 network interface BOB SIMITH circuit, remove the high-voltage capacitance of SIMITH circuit, adjust the resistance value of SIMITH circuit, perhaps whole removal SIMITH circuit, adjustment to network transformer centre cap filter capacitor, the network interface of 100M/1000M, tap is adjusted into the patch capacitor parallel connection of 1NF and 100NF, as far as possible near network transformer, can use both sides that the network transformer of COMON CHOKE is arranged to voltage driven type PHY, perhaps three-terminal network transformer can well suppress the common mode radiation that network interface brings out with the network transformer of self coupling coil.In the situation that do not consider cost, can add the magnet ring that size is suitable at netting twine in addition.
As shown in Figure 6, described adjustment scheme 5: process the noise that is coupled to VOIP by the network interface partial noise, because the plank size is controlled, it is very little that general home gateway class communication terminal plank is all done, that leans between several interfaces is very near, especially the RJ45 interface of the RJ11 interface of VOIP and network interface lean on very near; Because the interference of ground noise easily makes the VOIP phone take a part of radiated noise out of near the leakage inductance of network transformer and the network interface, near the network interface SIMITH circuit high-voltage capacitance of removing VOIP can effectively reduce network interface and be coupled to the interference of VOIP;
As shown in Figure 7, described adjustment scheme 6: the radiated noise that brings out on the inhibition 12V input line, the preferred 25mH of common mode inductance value, because home gateway class communication terminal is with regard to a 12V input port, at the inner complicated cabling situation of the plank noise that a part of chip brings that may be coupled, radiate from the 12V input line, at this time add upper magnetic ring on the 12V input power cord again, perhaps add that in the 12V input common mode inductance can both effectively solve the radiation-induced radiation of power line and exceed standard.
A kind of home gateway class communication terminal is failed another embodiment of the method for adjustment by radiation-emitting harassing and wrecking test according to the present invention, so-called home gateway class communication terminal is tested the frequency that refers between 30-230MHZ in 10 meters darkrooms by the radiation-emitting harassing and wrecking, quasi-peak value is below 30db (uv/m), between the frequency of 230-1000MHZ, quasi-peak value is at 37db(uv/m) below and in AV value that 1GHZ-3GHZ records below 50db (uv/m), the PK value is below 70db (uv/m), and what the data communication device that records was like this crossed is CLASS B grade.
A kind of home gateway class communication terminal is failed another embodiment of the method for adjustment by radiation-emitting harassing and wrecking test according to the present invention, in the described adjustment scheme 1, described RX_CLK, the build-out resistor of the upper use of TX_CLK is 49.9 ohm-150 ohm, preferred 75 ohm.
A kind of home gateway class communication terminal is failed another embodiment of the method for adjustment by radiation-emitting harassing and wrecking test according to the present invention, in the described adjustment scheme 4, and the filter capacitor of the parallel combination of a pair of 1NF of network transformer centre cap and 100NF.
Claims (4)
1. a home gateway class communication terminal fails to harass the method for adjustment of testing by radiation-emitting, it is characterized in that: may further comprise the steps:
Step 1, when carrying out radiation-emitting harassing and wrecking test, whether the equipment of at first checking harasses the grade that requires by radiation-emitting, the standard code device interior source frequency of described radiation-emitting harassing and wrecking test only proceeds to 1GHZ when being lower than the 108MHZ measurement, 108M-500MHZ then measures 2GHZ, and home gateway communication terminal inside sources frequency is at 108MHZ-500MHZ;
Step 2 if radiation-emitting harassing and wrecking test is not passed through, check it is that the antenna horizontal checkout is not passed through, or the antenna vertical checkout is not passed through;
Step 3, analyzing noise is by the veneer internal radiation out, or by the signaling interface tape out;
Step 4 for veneer internal radiation situation out, finally adopts adjustment scheme 1, adjustment scheme 2 and adjustment scheme 3, for the situation that the external signal mouth radiates, finally adopts adjustment scheme 4, adjustment scheme 5 and adjustment scheme 6;
Described adjustment scheme 1: the harmonic wave of the 125M frequency multiplication that PHY is produced is processed, check the filter design of PHY power supply, with analog power and the digital power isolation of magnetic bead with PHY, prevent the noise conduction, the power supply that PHY is used carries out filtering reinforcement, the electric capacity that uses 0.1UF-10UF not wait, the upper CLK that communicates by letter with MAC of PHY is adjusted processing, with RX_CLK, TX_CLK carries out resistors match, and resistance is between 49.9 ohm and 150 ohm;
Described adjustment scheme 2: the harmonic wave to the 480M frequency multiplication is processed, because 480M can determine to be caused by USB interface, directly check placement-and-routing's situation of USB, whether USB difference cabling is selected in suitable layer, avoid cutting a layer cabling, whether the differential lines that checks USB is walked in board edge to cause signal with reference to deficiency, and cabling is arranged on more than the interior 100mil of plate;
Described adjustment scheme 3: to frequency is suppressed by the envelope that power supply causes between 30M-100MHZ;
Described adjustment scheme 4: to the adjustment of RJ45 network interface BOB SIMITH circuit, remove the high-voltage capacitance of SIMITH circuit, adjust the resistance value of SIMITH circuit, perhaps whole removal SIMITH circuit, adjustment to network transformer centre cap filter capacitor, the network interface of 100M/1000M, tap are adjusted into the patch capacitor parallel connection of 1NF and 100NF, as far as possible near network transformer;
Described adjustment scheme 5: process the noise that is coupled to VOIP by the network interface partial noise;
Described adjustment scheme 6: the radiated noise that brings out on the inhibition 12V input line.
2. a kind of home gateway class communication terminal according to claim 1 fails to harass the method for adjustment of testing by radiation-emitting, it is characterized in that: so-called home gateway class communication terminal is tested the frequency that refers between 30-230MHZ in 10 meters darkrooms by the radiation-emitting harassing and wrecking, quasi-peak value is below 30db (uv/m), between the frequency of 230-1000MHZ, quasi-peak value is at 37db(uv/m) below and in AV value that 1GHZ-3GHZ records below 50db (uv/m), the PK value is below 70db (uv/m), and what the data communication device that records was like this crossed is CLASS B grade.
3. a kind of home gateway class communication terminal according to claim 1 fails to harass the method for adjustment of testing by radiation-emitting, it is characterized in that: in the described adjustment scheme 1, and described RX_CLK, the build-out resistor of the upper use of TX_CLK is 49.9 ohm-150 ohm.
4. a kind of home gateway class communication terminal according to claim 1 fails to harass the method for adjustment of testing by radiation-emitting, it is characterized in that: in the described adjustment scheme 4, the filter capacitor of the parallel combination of a pair of 1NF of network transformer centre cap and 100NF.
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| CN107070562A (en) * | 2017-04-10 | 2017-08-18 | 晶晨半导体(上海)有限公司 | A kind of circuit for improving network interface electromagnetic interference |
| CN107179457A (en) * | 2017-05-25 | 2017-09-19 | 上海市共进通信技术有限公司 | The method of adjustment that home gateway class communication terminal is tested by esd immunity |
| CN107741531A (en) * | 2017-09-07 | 2018-02-27 | 郑州云海信息技术有限公司 | The Low emissivity processing system and method for testing of a kind of server admin network interface |
| CN110018408A (en) * | 2019-03-22 | 2019-07-16 | 太仓市同维电子有限公司 | A kind of home gateway class communication terminal fails the method for adjustment tested by conduction interference |
| CN112083245A (en) * | 2020-09-09 | 2020-12-15 | 广州云从洪荒智能科技有限公司 | Target object electromagnetic radiation disturbance testing method, system, equipment and medium |
| CN112866837A (en) * | 2020-12-31 | 2021-05-28 | 广州芯德通信科技股份有限公司 | Network port radiation suppression circuit for OLT equipment and design method |
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| CN112866837A (en) * | 2020-12-31 | 2021-05-28 | 广州芯德通信科技股份有限公司 | Network port radiation suppression circuit for OLT equipment and design method |
| CN112866837B (en) * | 2020-12-31 | 2021-10-26 | 广州芯德通信科技股份有限公司 | Network port radiation suppression circuit for OLT equipment and design method |
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