Ngokufika kwexesha lolwazi, ukusetyenziswa kweebhodi ze-pcb kuya kubanda kakhulu, kwaye ukuphuhliswa kweebhodi ze-pcb kuya kuba nzima ngakumbi.Njengoko izinto ze-elektroniki zicwangciswa ngakumbi nangakumbi kwi-PCB, ukuphazamiseka kombane kuye kwaba yingxaki engenakuthintelwa.Ekuqulunqweni nasekusetyenzisweni kweebhodi ezininzi, umgca wesignali kunye noluhlu lwamandla kufuneka luhlulwe, ngoko ukuyila kunye nokulungiswa kwe-stack kubaluleke kakhulu.Iskimu esihle soyilo sinokunciphisa kakhulu impembelelo ye-EMI kunye ne-crosstalk kwiibhodi ezininzi.
Xa kuthelekiswa neebhodi eziqhelekileyo zomgangatho omnye, uyilo lweebhodi ezinamanqwanqwa amaninzi zongeza iileyiti zesignali, iileya ze-wiring, kwaye zicwangcisa iileyile zamandla ezizimeleyo kunye neengqimba zomhlaba.Iingenelo zeebhodi ezinamanqwanqwa amaninzi zibonakaliswa ngokukodwa ekunikezeni i-voltage ezinzileyo yokuguqulwa kwesignali yedijithali, kunye nokongeza ngokulinganayo amandla kwicandelo ngalinye ngexesha elifanayo, ngokufanelekileyo ukunciphisa ukuphazamiseka phakathi kweempawu.
Unikezelo lwamandla lusetyenziswa kwindawo enkulu yokubeka ubhedu kunye nomgangatho womhlaba, onokunciphisa kakhulu ukuchasana komgangatho wamandla kunye nomgangatho womhlaba, ukuze i-voltage kumaleko ombane izinzile, kunye neempawu zomgca wophawu ngalunye. inokuqinisekiswa, enenzuzo kakhulu kwi-impedance kunye nokunciphisa i-crosstalk.Ekuqulunqweni kweebhodi zeesekethe eziphezulu, kuye kwacaciswa ngokucacileyo ukuba ngaphezu kwe-60% ye-stacking schemes kufuneka isetyenziswe.Iibhodi ezinomaleko amaninzi, iimpawu zombane, kunye nokucinezelwa kwemitha yemitha ye-electromagnetic zonke zineengenelo ezingenakuthelekiswa nanto kwiibhodi ezinomgangatho ophantsi.Ngokumalunga neendleko, ngokuqhelekileyo, xa kukho iileya ezininzi, ixabiso libiza kakhulu, kuba iindleko zebhodi ye-PCB zihambelana nenani leeleya, kunye nobuninzi beyunithi yendawo nganye.Emva kokunciphisa inani leengqimba, indawo ye-wiring iya kuncitshiswa, ngaloo ndlela ikhulise ubuninzi be-wiring., kunye nokuhlangabezana neemfuno zoyilo ngokunciphisa ububanzi bomgca kunye nomgama.Oku kunokunyusa iindleko ngokufanelekileyo.Kunokwenzeka ukunciphisa ukupakisha kunye nokunciphisa iindleko, kodwa kwenza ukusebenza kombane kubi nakakhulu.Olu hlobo loyilo ludla ngokuphikisana.
Ukujonga i-PCB microstrip wiring kwimodeli, umaleko womhlaba unokubonwa njengenxalenye yomgca wothumelo.Umaleko wobhedu womhlaba ungasetyenziswa njengendlela yomgca wesignali yelophu.Inqwelomoya yamandla idityaniswe kwinqwelomoya ephantsi ngokusebenzisa i-decoupling capacitor, kwimeko ye-AC.Zombini ziyalingana.Umahluko phakathi kwe-frequency ephantsi kunye ne-high-frequency loops yangoku kukuba.Kwi-frequencies ephantsi, i-return current ilandela indlela yokuchasana okuncinci.Kwii-frequencies eziphezulu, i-return current isendleleni ye-inductance encinci.Imbuyekezo yangoku, igxininiswe kwaye isasazwe ngokuthe ngqo ngaphantsi kweempawu zomqondiso.
Kwimeko ye-frequency ephezulu, ukuba ucingo lubekwe ngokuthe ngqo kumqolo womhlaba, nokuba kukho iilophu ezininzi, imbuyekezo yangoku iya kubuyela kumthombo wesignali ukusuka kuluhlu lwe-wiring phantsi kwendlela yokuqala.Ngenxa yokuba le ndlela ineyona nto incinci yokungathinteli.Olu hlobo lokusetyenziswa kwe-capacitive coupling enkulu ukucinezela intsimi yombane, kunye neyona ndlela incinci yokudibanisa i-capacitive ukucinezela isityalo somagnetic ukugcina ukusabela okuphantsi, sikubiza ngokuba yi-self-shielding.
Inokubonwa kwifomyula ukuba xa i-current igeleza ngasemva, umgama ukusuka kumgca wesignali uhambelana ngokungafaniyo nobuninzi bangoku.Oku kunciphisa indawo ye-loop kunye ne-inductance.Ngexesha elifanayo, kunokugqitywa ukuba ukuba umgama phakathi komgca wesignali kunye ne-loop usondele, imisinga yezo zimbini zifana nobukhulu kwaye zichasene nolwalathiso.Kwaye intsimi yamagnetic eveliswa yindawo yangaphandle inokulungiswa, ngoko ke i-EMI yangaphandle nayo incinci kakhulu.Kuyilo lwe-stack, kungcono ukuba umkhondo wesignali ngamnye uhambelane nomgangatho osondeleyo womhlaba.
Kwingxaki ye-crosstalk kwi-ground layer, i-crosstalk ebangelwa yimijikelezo ephezulu ye-frequency ikakhulu ngenxa yokudibanisa i-inductive.Ukusuka kwifomula yelophu yangoku engentla, kunokugqityezelwa ukuba imisinga yeluphu eveliswa yimigca yophawu emibini esondeleleneyo iya kuthi xhaxhe.Ngoko kuya kubakho ukuphazamiseka kwamagnetic.
I-K kwifomula inxulumene nexesha lokunyuka kwesignali kunye nobude bomgca wesignali yokuphazamiseka.Kwimeko ye-stack, ukunciphisa umgama phakathi komgangatho wesignali kunye nomgangatho womhlaba uya kunciphisa ngokufanelekileyo ukuphazamiseka kwinqanaba lomhlaba.Xa ubeka ubhedu kumandla ombane kunye nomgangatho womhlaba kwi-wiring ye-PCB, udonga lokwahlula luya kubonakala kwindawo yokubeka ubhedu ukuba awuyi kuqwalasela.Ukwenzeka kolu hlobo lwengxaki kusenokwenzeka ukuba kungenxa yoxinaniso oluphezulu lwemingxuma, okanye uyilo olungekho ngqiqweni lokudlula kwindawo yokwahlula.Oku kunciphisa ixesha lokunyuka kwaye kwandisa indawo ye-loop.I-Inductance iyanda kwaye idala i-crosstalk kunye ne-EMI.
Kufuneka sizame konke okusemandleni ethu ukuseka abaphathi beevenkile ngababini.Oku kukuqwalasela iimfuno zesakhiwo sokulinganisela kwinkqubo, kuba isakhiwo esingalinganiyo sinokubangela ukuguqulwa kwebhodi ye-pcb.Kumaleko omqondiso ngamnye, kungcono ukuba nesixeko esiqhelekileyo njengesithuba.Umgama phakathi konikezelo lwamandla oluphezulu kunye nesixeko sobhedu ulungele ukuzinza kunye nokunciphisa i-EMI.Kuyilo lwebhodi yesantya esiphezulu, iinqwelomoya zomhlaba ezingafunekiyo zingongezwa ukwahlula iindiza zemiqondiso.
Ixesha lokuposa: Mar-23-2023