Mukugadzirwa kwePCB, kuenderana kwemagetsi (EMC) uye kukanganiswa kwemagetsi (EMI) kwagara kwave kuri misoro mikuru miviri kune mainjiniya, kunyanya mudhizaini yemazuva ano edunhu redhizaini uye mapakeji echikamu ari kuramba achidzikira, maOEM anoda masisitimu ekumhanya.Muchikamu chino, ini ndichagovera maitiro ekudzivirira matambudziko emagetsi muPCB dhizaini.
1. Crosstalk uye alignment ndiyo inotarisa
Kururamisa kunonyanya kukosha kuve nechokwadi chekuyerera kwakakodzera kwezvino.Kana iyo ikozvino ichibva kune oscillator kana chimwe chigadziro chakafanana, zvinonyanya kukosha kuchengetedza ikozvino yakaparadzana kubva pasi pevhu, kana kuchengetedza ikozvino kuti irege kushanda pamwe chete nekumwe kurongeka.Masaini maviri akakwira-kumhanya anoenderana anogona kugadzira EMC uye EMI, kunyanya crosstalk.Zvakakosha kuchengetedza nzira dzekudzivirira dzipfupi sezvinobvira uye nzira dzemazuva ano dzekudzoka dzipfupi sezvinobvira.Kureba kwenzira yekudzoka kunofanirwa kufanana nehurefu hwenzira yekutumira.
Kune EMI, imwe nzira inonzi "nzira yekutyora" uye imwe yacho "nzira yeakabatwa".Inductive uye capacitive coupling inokanganisa nzira ye "akabatwa" nekuda kwekuvapo kwemagineti emagetsi, nekudaro ichigadzira kumberi nekudzosera kumashure mafungu pa "nzira yevakabatwa".Nenzira iyi, ripple inogadzirwa munzvimbo yakagadzikana iyo iyo inotumira uye kugamuchira hurefu hwechiratidzo inenge yakaenzana.
Munzvimbo yakanyatsogadzikana ine mitsetse yakagadzikana, iyo induced currents inofanira kukanzura mumwe nemumwe kunze, nokudaro kubvisa crosstalk.Zvisinei, tiri munyika isina kukwana umo zvinhu zvakadaro zvisingaitiki.Naizvozvo, chinangwa chedu ndechekuti crosstalk inofanirwa kuchengetwa iri shoma kune ese magadzirirwo.Mhedzisiro yecrosstalk inogona kudzikiswa kana hupamhi pakati pemitsara inofanana yakapetwa kaviri upamhi hwemitsara.Semuyenzaniso, kana hupamhi hwemutsara huri 5 mils, nhambwe shoma pakati pemitsara miviri inofambirana inofanira kunge iri miriyoni gumi kana kupfuura.
Sezvo zvinhu zvitsva uye zvikamu zvichiramba zvichionekwa, vagadziri vePCB vanofanirwawo kuramba vachibata neEMC uye nekukanganisa nyaya.
2. Decoupling capacitors
Decoupling capacitors inoderedza zvisingadiwe mhedzisiro yecrosstalk.Iwo anofanirwa kunge ari pakati pesimba uye pasi pini zvechishandiso, izvo zvinoita kuti yakaderera AC impedance uye inoderedza ruzha uye crosstalk.Kuti uwane yakaderera impedance pane yakafara frequency renji, akawanda decoupling capacitors anofanirwa kushandiswa.
Nheyo yakakosha yekuisa decoupling capacitors ndeyekuti iyo capacitor ine yakaderera capacitance kukosha inoiswa padyo nemudziyo sezvinobvira kuderedza inductive mhedzisiro pane alignments.Iyi chaiyo capacitor inofanirwa kuiswa padyo sezvinobvira kune mudziyo wemagetsi mapini kana magetsi emagetsi mujaho uye mapedhi eiyo capacitor anofanirwa kubatanidzwa zvakananga kune vias kana pasi nhanho.Kana kurongeka kwakarebesa, shandisa ma vias akawanda kuti uderedze kukanganiswa kwepasi.
3. Kugadzika PCB
Nzira yakakosha yekudzikisa EMI kugadzira iyo PCB yepasi pasi.Danho rekutanga nderekuita kuti nzvimbo yepasi ive yakakura sezvinobvira mukati menzvimbo yese yePCB board kuitira kuti emissions, crosstalk uye ruzha zvideredzwe.Kunyanya kutarisirwa kunofanira kutorwa kana uchibatanidza chikamu chimwe nechimwe kune imwe nzvimbo yepasi kana pasi, pasina iyo iyo neutralizing effect yeyakavimbika grounding layer haigoni kushandiswa zvizere.
Iyo yakanyanya kuomarara PCB dhizaini ine akati wandei akagadzikana voltages.Sezvineiwo, yega yega referensi voltage ine yayo inoenderana grounding layer.Nekudaro, akawandisa ekuisa pasi anogona kuwedzera mutengo wekugadzira wePCB uye kuita kuti idhure.Chibvumirano ndechekushandisa mitsara yepasi munzvimbo nhatu kusvika shanu dzakasiyana, imwe neimwe inogona kuve nezvikamu zvepasi zvakati wandei.Izvi hazvidzore chete mutengo wekugadzira webhodhi, asi zvakare zvinoderedza EMI neEMC.
Iyo yakaderera impedance grounding system yakakosha kana EMC ichizodzikiswa.Mune multilayer PCB zviri nani kuve neakavimbika grounding layer pane yendarira balance block (copper kuba) kana yakapararira pasi pasi sezvo ine yakaderera impedance, inopa nzira yazvino uye ndiyo yakanakisa sosi yekudzosera kumashure masaini.
Hurefu hwenguva iyo chiratidzo chinotora kudzokera pasi kwakakosha zvakare.Iyo nguva inotorwa kuti chiratidzo chifambe kuenda nekubva kwacho chinofanirwa kufananidzwa, zvikasadaro antenna-senge chiitiko chichaitika, ichibvumira iyo inopenya simba kuve chikamu cheEMI.Saizvozvo, kurongeka kweiyo yazvino kusvika / kubva kuchiratidzo sosi kunofanirwa kunge kupfupi sezvinobvira, kana kwainobva uye nzira dzekudzoka dzisiri dzehurefu hwakaenzana, kuputika kwepasi kuchaitika uye izvi zvichagadzirawo EMI.
4. Dzivisa 90 ° angles
Kuti uderedze EMI, kurongeka, vias uye zvimwe zvikamu zvinofanirwa kudziviswa kuumba 90 ° kona, nekuti kona yekurudyi inoburitsa mwaranzi.Kuti udzivise 90 ° angle, kurongeka kunofanirwa kunge kuri maviri 45 ° angle wiring kukona.
5. Kushandiswa kwepamusoro-gomba kunoda kuchenjerera
Munenge ose PCB marongerwo, vias anofanira kushandiswa kupa conductive kubatana pakati siyana akaturikidzana.Mune zvimwe zviitiko, ivo vanoburitsawo zvinoratidzira, sezvo hunhu impedance inochinja kana vias zvinogadzirwa mukurongeka.
Zvakakoshawo kuyeuka kuti vias kuwedzera kureba kurongeka uye vanoda kufananidzwa.Panyaya yekusiyanisa kurongeka, vias zvinofanirwa kudziviswa pazvinogoneka.Kana izvi zvisingakwanisi kudziviswa, vias inofanira kushandiswa mukugadzirisa zvose kuripa kunonoka kwechiratidzo uye nzira dzekudzoka.
6. Cables uye kudzivirirwa kwemuviri
Matambo anotakura maseketi edhijitari uye analogue currents anogona kugadzira parasitic capacitance uye inductance, zvichikonzera matambudziko mazhinji ane chekuita neEMC.Kana tambo dzakamonyoroka dzepairi dzakashandiswa, mwero wakaderera wekubatanidza unochengetedzwa uye magineti anogadzirwa anobviswa.Kune masaini akakwira frequency, tambo dzakadzivirirwa dzinofanirwa kushandiswa, idzo dzese kumberi nekumashure dzakadzika, kubvisa kukanganiswa kweEMI.
Kudzivirira muviri ndiko kuvharirwa kwese kana chikamu chesisitimu mupakeji yesimbi kudzivirira EMI kupinda muPCB wedunhu.Iyi inodzivirira inoita seyakavharika, inobata pasi-capacitor, ichidzikisa saizi yeantenna loop uye inonwisa EMI.
Nguva yekutumira: Nov-23-2022