Kuye kwathiwa kunezinhlobo ezimbili kuphela zonjiniyela be-elekthronikhi emhlabeni: labo abaye babhekana nokuphazanyiswa nguzibuthe kagesi nalabo abangakaze babhekane nakho. Ngokukhula kwemvamisa yesiginali ye-PCB, ukwakheka kwe-EMC kuyinkinga okufanele siyicabangele
1. Izibaluli ezinhlanu ezibalulekile okufanele zicatshangelwe phakathi nokuhlaziywa kwe-EMC
Uma ubhekene nomklamo, kunezici ezinhlanu ezibalulekile okufanele uzicabangele lapho wenza ukuhlaziywa kwe-EMC komkhiqizo nomklamo:
1). Usayizi wedivayisi engukhiye:
Ubukhulu bomzimba bomshini okhiphayo okhiqiza imisebe. I-radio frequency (RF) yamanje izodala inkambu ye-electromagnetic, ezovuza endlini futhi iphume endlini. Ubude bekhebula ku-PCB njengendlela yokudlulisela inomthelela oqondile ku-RF yamanje.
2). Ukulinganisa kwe-impedance
Umthombo kanye ne-receiver impedances, kanye ne-impedance yokudlulisela phakathi kwabo.
3). Izici zesikhashana zezimpawu zokuphazamiseka
Ingabe inkinga iwumcimbi oqhubekayo (wesiginali yesikhathi), noma umjikelezo wokusebenza othize kuphela (isb. umcimbi owodwa ungaba ukuchofoza ukhiye noma ukuphazamiseka kwamandla, ukusebenza kwedrayivu yediski ngezikhathi ezithile, noma ukuqhuma kwenethiwekhi)
4). Amandla esignali yokuphazamiseka
Iqine kangakanani izinga lamandla omthombo, futhi mangakanani amandla onawo okukhiqiza ukuphazamiseka okuyingozi
5).Izici zokuvama kwamasignali okuphazamisa
Usebenzisa i-spectrum analyzer ukuze ubheke i-waveform, bheka lapho inkinga yenzeka khona ku-spectrum, okulula ukuyithola inkinga.
Ngaphezu kwalokho, eminye imikhuba yokuklama imvamisa ephansi idinga ukunakwa. Isibonelo, isisekelo sephuzu elilodwa esivamile sifaneleka kakhulu izinhlelo zokusebenza zefrikhwensi ephansi, kodwa ayifanele amasiginali e-RF lapho kunezinkinga ezengeziwe ze-EMI.
Kukholakala ukuthi abanye onjiniyela bazosebenzisa isisekelo sephuzu elilodwa kuyo yonke imiklamo yemikhiqizo ngaphandle kokuqaphela ukuthi ukusetshenziswa kwale ndlela yokumisa kungase kudale izinkinga eziningi noma eziyinkimbinkimbi ze-EMC.
Kufanele futhi sinake ukugeleza kwamanje ezingxenyeni zesifunda. Kusukela olwazini lwesifunda, siyazi ukuthi i-current igeleza isuka ku-voltage ephezulu iye ku-voltage ephansi, futhi okwamanje igeleza njalo ngomzila owodwa noma ngaphezulu kumjikelezo we-loop evaliwe, ngakho-ke kukhona umthetho obaluleke kakhulu: klama i-loop encane.
Kulezo zikhombisi-ndlela lapho ukuphazanyiswa kwamanje kukalwa, izintambo ze-PCB ziyashintshwa ukuze zingathinti umthwalo noma isekethe ebucayi. Izinhlelo zokusebenza ezidinga indlela ephezulu yokuvimba ukusuka ekunikezeni amandla ukuya ekulayishweni kufanele zicabangele zonke izindlela ezingaba khona lapho amandla okubuyisela angageleza khona.
Kudingeka futhi sinake izintambo ze-PCB. I-impedance yocingo noma umzila iqukethe ukumelana no-R kanye nokusabela kwe-inductive. Kumafrikhwensi aphezulu, kukhona i-impedance kodwa akukho ukusabela kwe-capacitive. Uma imvamisa yocingo ingaphezu kuka-100kHz, intambo noma intambo iba inductor. Izintambo noma izintambo ezisebenza ngaphezu komsindo zingase zibe izinti ze-RF.
Ezicacisweni ze-EMC, izintambo noma izintambo azivunyelwe ukusebenza ngaphansi kuka-λ/20 wefrikhwensi ethile (i-antenna yakhelwe ukuthi ibe ngu-λ/4 noma λ/2 wefrikhwensi ethile). Uma ingaklanyelwe ngaleyo ndlela, izintambo ziba i-antenna esebenza kahle kakhulu, okwenza ukulungisa iphutha kamuva kube nzima nakakhulu.
2.Isakhiwo se-PCB
Okokuqala: Cabangela ubukhulu be-PCB. Uma ubukhulu be-PCB bukhulu kakhulu, amandla okuvimbela ukuphazamiseka kwesistimu ayancipha futhi izindleko zikhuphuka ngokunyuka kwezintambo, kuyilapho ubukhulu buncane kakhulu, okubangela kalula inkinga yokushisa nokuphazamisana.
Okwesibili: nquma indawo yezingxenye ezikhethekile (njengezakhi zewashi) (izintambo zewashi kungcono kakhulu zingabekwa phansi futhi ungahambi emigqeni yesignali eyinhloko, ukugwema ukuphazamiseka).
Okwesithathu: ngokusho komsebenzi wesifunda, ukwakheka okuphelele kwe-PCB. Ekuhlelweni kwengxenye, izingxenye ezihlobene kufanele zisondele ngangokunokwenzeka, ukuze kutholwe umphumela ongcono wokulwa nokuphazamiseka.