Ngenxa yeempawu zokutshintsha kombane wokutshintsha, kulula ukubangela unikezelo lombane lokutshintsha ukuvelisa ukuphazamiseka okukhulu kokuhambelana kwe-electromagnetic.Njengenjineli yobonelelo lwamandla, injineli ehambelana ne-electromagnetic, okanye injineli yoyilo lwePCB, kuya kufuneka uqonde oonobangela beengxaki zokuhambelana kwe-electromagnetic kwaye uzisombulule iindlela, ngakumbi iinjineli zoyilo kufuneka zazi indlela yokuphepha ukwanda kweendawo ezimdaka.Eli nqaku ikakhulu lazisa amanqaku aphambili ombane uyilo lwePCB.
15. Nciphisa indawo ye-loop yesignali echaphazelekayo (ebuthathaka) kunye nobude be-wiring ukunciphisa ukuphazamiseka.
16. Iimpawu ezincinci zomqondiso zikude kakhulu kwimigca yesignali ye-dv / dt enkulu (njenge-C pole okanye i-D pole ye-tube yokutshintsha, i-buffer (i-snubber) kunye ne-clamp network) ukunciphisa ukudibanisa, kunye nomhlaba (okanye unikezelo lwamandla, ngokufutshane) Umqondiso onokwenzeka) ukunciphisa ngakumbi ukudibanisa, kunye nomhlaba kufuneka udibane kakuhle nenqwelomoya.Kwangaxeshanye, imiqondiso emincinci yeempawu kufuneka ibe kude kangangoko kunokwenzeka ukusuka kwimigca yesignali ye-di/dt enkulu ukuthintela ukuphambana kwe-inductive.Kungcono ukuba ungangeni phantsi kwesignali enkulu ye-dv/dt xa isignali encinci ilandelela.Ukuba umva womzila omncinci womqondiso unokusekwa (umhlaba ofanayo), umqondiso wengxolo odityaniswe nawo unokuncitshiswa.
17. Kungcono ukubeka umhlaba ujikeleze kwaye ngasemva kwezi zibonakaliso ezinkulu ze-dv/dt kunye ne-di/dt (kubandakanywa nezibonda ze-C/D zezixhobo zokutshintsha kunye ne-radiator ityhubhu yokutshintsha), kwaye usebenzise phezulu nangaphantsi. iileya zomhlaba Ngokudibanisa umngxuma, kwaye udibanise lo mhlaba kwindawo eqhelekileyo yomhlaba (ngokuqhelekileyo isibonda se-E / S setyhubhu yokutshintsha, okanye isampuli ye-resistor) kunye nomkhondo ophantsi we-impedance.Oku kunokunciphisa i-EMI elayishiwe.Kufuneka kuqatshelwe ukuba umgangatho omncinci womqondiso akufanele udibaniswe kulo mhlaba wokukhusela, ngaphandle koko uya kwazisa ukuphazamiseka okukhulu.Izalathisi ezinkulu zedv/dt zihlala ziphazamisana neradiyetha kunye nomhlaba okufutshane ngokuhambelana.Kungcono ukudibanisa i-radiator ityhubhu yokutshintsha kwindawo yokukhusela.Ukusetyenziswa kwezixhobo zokutshintshela phezulu kuya kunciphisa i-capacitance efanayo, ngaloo ndlela kuncitshiswe ukudibanisa.
18. Kungcono ukuba ungasebenzisi i-vias kwiitrayisi ezithanda ukuphazamisa, njengoko kuya kuphazamisa zonke iileya ezidlulayo.
19. Ukukhusela kunokunciphisa i-EMI ye-radiated, kodwa ngenxa yokwanda kwe-capacitance kumhlaba, i-EMI eqhutywe (imodi eqhelekileyo, okanye imodi yokwahlukana yangaphandle) iya kwanda, kodwa ngokude nje ukuba i-shielding layer isekelwe ngokufanelekileyo, ayiyi kunyuka kakhulu.Inokuqwalaselwa kuyilo lwangempela.
20. Ukuthintela ukuphazamiseka okuqhelekileyo kwe-impedance, sebenzisa i-grounding point kunye nokunikezelwa kwamandla ukusuka kwindawo enye.
21. Ukutshintsha umbane wamandla ngokuqhelekileyo kunezizathu ezintathu: amandla okufaka amandla aphezulu akhoyo ngoku, amandla okuvelisa umhlaba ophezulu wangoku, kunye nomhlaba omncinci wokulawula umqondiso.Indlela yoqhagamshelo lomhlaba iboniswe kulo mzobo ulandelayo:
22. Xa ubeka umhlaba, qala ugwebe ubunjani bomhlaba phambi kokuba udibanise.Umhlaba wesampulu kunye nokukhulisa impazamo ngokuqhelekileyo kufuneka udityaniswe kwipali engalunganga yecapacitor ephumayo, kwaye umqondiso wesampulu kufuneka uqhele ukukhutshwa kwipali elungileyo yecapacitor ephumayo.Umgangatho omncinci wokulawula umqondiso kunye nomhlaba wokuqhuba kufuneka udibaniswe ngokuqhelekileyo kwi-pole ye-E / S okanye i-sampling resistor ye-tube yokutshintsha ngokulandelanayo ukukhusela ukuphazamiseka okuqhelekileyo kwe-impedance.Ngokuqhelekileyo umhlaba olawulayo kunye nomhlaba wokuqhuba we-IC awuholelwanga ngokwahlukileyo.Ngeli xesha, i-impedance ekhokelayo ukusuka kwisampulu yokumelana nesampulu ukuya kumhlaba ongentla kufuneka ibe yincinci kangangoko kunokwenzeka ukunciphisa ukuphazamiseka okuqhelekileyo kunye nokuphucula ukuchaneka kwesampulu yangoku.
23. I-voltage ye-output ye-sampling network ingcono ukuba isondele kwi-amplifier yephutha kunokuba iphume.Oku kungenxa yokuba iisignali ze-impedance eziphantsi zisengozini yokuphazamiseka kuneempawu eziphezulu ze-impedance.Imikhondo yesampulu kufuneka isondelelene kangangoko ukuze kuncitshiswe ingxolo echongiweyo.
24. Nika ingqalelo kwi-layout of inductors ukuba ibe kude kunye ne-perpendicular omnye komnye ukuze kuncitshiswe i-mutual inductance, ngakumbi i-inductors yokugcina amandla kunye ne-filter inductors.
25. Nika ingqalelo kwi-layout xa i-high-frequency capacitor kunye ne-low-frequency capacitor isetyenziswe ngokufanayo, i-high-frequency capacitor isondele kumsebenzisi.
26. Ukuphazamiseka kwe-low-frequency interference generally differential mode (ngaphantsi kwe-1M), kunye nokuphazamiseka kwe-high-frequency interference ngokubanzi kuyindlela eqhelekileyo, ngokuqhelekileyo idibaniswe yimitha.
27. Ukuba isignali ye-frequency ephezulu idibene ne-input lead, kulula ukwenza i-EMI (imodi eqhelekileyo).Ungafaka ikhonkco lamagnetic kwi-input lead kufutshane nombane.Ukuba i-EMI iyancitshiswa, ibonisa le ngxaki.Isisombululo sale ngxaki kukunciphisa ukudibanisa okanye ukunciphisa i-EMI yesekethe.Ukuba ingxolo ye-high-frequency ayihluzwanga kwaye iqhutywe kwi-input lead, i-EMI (imowudi eyahlukileyo) nayo iya kwenziwa.Ngeli xesha, i-ring magnetic ayikwazi ukusombulula ingxaki.Intambo ezimbini ze-high-frequency inductors (symmetrical) apho igalelo elikhokelela lisondele kunikezelo lwamandla.Ukuncipha kubonisa ukuba le ngxaki ikhona.Isisombululo sale ngxaki kukuphucula ukuhluza, okanye ukunciphisa ukuveliswa kwengxolo ye-high-frequency nge-buffering, clamping kunye nezinye iindlela.
28. Umlinganiselo wendlela yokwahlula kunye nemowudi eqhelekileyo yangoku:
29. Isihlungi se-EMI kufuneka sibe sisondele kumgca ongenayo ngokusemandleni, kwaye i-wiring yomgca ongenayo kufuneka ibe mfutshane ngokunokwenzeka ukunciphisa ukudibanisa phakathi kwamanqanaba angaphambili nasemva kwe-EMI filter.Ucingo olungenayo lukhuseleke kakuhle kumhlaba we-chassis (indlela ichazwe ngasentla).Isihluzo se-EMI semveliso kufuneka siphathwe ngokufanayo.Zama ukwandisa umgama phakathi komgca ongenayo kunye ne-high dv/dt trace yesiginali, kwaye uyiqwalasele kuyilo.