Isetshenziswa kanjani PCB ngokukhipha ukushisa kwephakheji ye-IC?

Isici sokuqala sedizayini ye-PCB engathuthukisa ukusebenza okushisayo ukwakheka kwedivayisi ye-PCB. Uma kungenzeka, izingxenye zamandla aphezulu ku-PCB kufanele zihlukaniswe zodwa. Lokhu kwehlukaniswa ngokomzimba phakathi kwezingxenye zamandla aphezulu kukhulisa indawo ye-PCB eduze nengxenye ngayinye yamandla aphezulu, ngalokho kusiza ukuzuza ukuqhutshwa kokushisa okungcono. Kufanele kuqashelwe ukuze kuhlukaniswe izingxenye ezizwela izinga lokushisa ku-PCB ezingxenyeni zamandla aphezulu. Uma kungenzeka, indawo yokufaka yezingxenye zamandla aphezulu kufanele ibe kude namakhona e-PCB. Indawo emaphakathi ye-PCB ingakhulisa indawo yebhodi ezungeze izingxenye zamandla aphezulu, ngaleyo ndlela isize ukuqeda ukushisa. Umfanekiso wesi-2 ubonisa izinto ezimbili ezifanayo ze-semiconductor: ingxenye A kanye nengxenye B. Ingxenye A itholakala ekhoneni le-PCB futhi inezinga lokushisa le-die junction elingaphezulu ngo-5% kunengxenye B ngenxa yokuthi ingxenye B itholakala eduze nendawo emaphakathi. Njengoba indawo yebhodi ezungeze ingxenye yokukhishwa kokushisa incane, ukuchithwa kokushisa ekhoneni lengxenye A kunqunyelwe.

Isetshenziswa kanjani i-PCB ekushiseni kwephakheji ye-IC?

Isici sesibili isakhiwo se-PCB, esinomthelela omkhulu ekusebenzeni okushisayo komklamo we-PCB. Umgomo ojwayelekile uthi: uma ithusi lithe xaxa ku-PCB, kulapho ukusebenza okushisayo kwezingxenye zesistimu kuphezulu. Isimo esifanelekile sokulahla ukushisa kwamadivayisi we-semiconductor ukuthi i-chip igibele isiqephu esikhulu sethusi elipholiswe uketshezi. Ezinhlelweni eziningi, le ndlela yokukhweza ayisebenzi, ngakho-ke singenza kuphela ezinye izinguquko ku-PCB ukuze sithuthukise ukusebenza kokukhipha ukushisa. Eziningi zezinhlelo zokusebenza namuhla, isamba sevolumu yesistimu siyaqhubeka nokuncipha, okunomthelela omubi ekusebenzeni kokukhipha ukushisa. I-PCB enkulu, indawo enkulu engasetshenziselwa ukuqhutshwa kokushisa, futhi inokuguquguquka okukhulu, okuvumela isikhala esanele phakathi kwezingxenye zamandla aphezulu.

Noma nini lapho kungenzeka, khulisa inombolo nokujiya kwezindiza ze-copper ground ze-PCB. Isisindo sogqinsi lwethusi ngokuvamile sikhulu, futhi kuyindlela enhle kakhulu yokushisa ukuze yonke i-PCB ikhiphe ukushisa. Ukuhlelwa kwe-wiring kwesendlalelo ngasinye kuzophinde kwandise inani eliphelele lethusi elisetshenziselwa ukuqhuba ukushisa. Kodwa-ke, le ntambo ivamise ukuhlukaniswa ngogesi nangokokushisa, okukhawulela indima yayo njengongqimba olungase lube khona lokukhipha ukushisa. Izintambo zendiza yaphansi yedivayisi kufanele zibe zikagesi ngangokunokwenzeka ngezindiza eziningi eziphansi, ukuze kusize ukukhulisa ukuqhutshwa kokushisa. I-vias yokukhipha ukushisa ku-PCB ngaphansi kwedivayisi ye-semiconductor isiza ukushisa ukuze kungene izingqimba ezigqitshiwe ze-PCB futhi kuqhube ngemuva kwebhodi lesifunda.

Ukuze uthuthukise ukusebenza kokukhipha ukushisa, izendlalelo ezingaphezulu neziphansi ze-PCB “ziyizindawo ezisagolide”. Sebenzisa izintambo ezibanzi futhi uzihambise kude namadivayisi anamandla amakhulu ukuze unikeze indlela eshisayo yokukhipha ukushisa. Ibhodi elishisayo elizinikele liyindlela enhle kakhulu yokushisa ukushisa kwe-PCB. Ibhodi elishisayo ngokuvamile litholakala phezulu noma ngemuva kwe-PCB, futhi lixhumeke ngokushisa ocingweni ngoxhumano lwethusi oluqondile noma nge-vias eshisayo. Endabeni yephakheji esemgqeni (amaphakheji anomkhondo nhlangothi zombili), lolu hlobo lwebhodi lokuqhuba ukushisa lungatholakala phezulu kwe-PCB futhi lumise okwe “ithambo lenja” (eliphakathi lincane njengephakheji, futhi indawo ekude nephakeji incane uma kuqhathaniswa.Inkulu, incane phakathi nendawo futhi inkulu ekugcineni). Endabeni yephakheji enezinhlangothi ezine (kukhona umkhondo kuzo zonke izinhlangothi ezine), ipuleti elibamba ukushisa kufanele libe ngemuva kwe-PCB noma ufake i-PCB.

Isetshenziswa kanjani i-PCB ekushiseni kwephakheji ye-IC?

Ukwandisa usayizi webhodi elishisayo kuyindlela enhle kakhulu yokuthuthukisa ukusebenza okushisayo kwephakheji ye-PowerPAD. Osayizi abahlukene bepuleti lokuqhuba ukushisa banethonya elikhulu ekusebenzeni okushisayo. Ishidi ledatha lomkhiqizo elinikezwe ngesimo sethebula ngokuvamile libhala lolu lwazi losayizi. Nokho, kunzima ukulinganisa umthelela wethusi owengeziwe wama-PCB angokwezifiso. Besebenzisa ezinye izibali eziku-inthanethi, abasebenzisi bangakhetha idivayisi bese bashintsha usayizi wephedi yethusi ukuze balinganisele umthelela wayo ekusebenzeni kokukhipha ukushisa kwama-PCB angewona awe-JEDEC. Lawa mathuluzi wokubala agqamisa umthelela wedizayini ye-PCB ekusebenzeni okushisayo. Kuphakheji enezinhlangothi ezine, indawo yephedi ephezulu incane nje kunendawo yephedi eveziwe yedivayisi. Kulesi simo, isendlalelo esingcwatshwe noma sangemuva siyindlela yokuqala yokufeza ukupholisa okungcono. Kumaphakheji akabili akulayini, singasebenzisa isitayela sephedi “yethambo lenja” ukuqeda ukushisa.

Okokugcina, amasistimu anama-PCB amakhulu angaphinde asetshenziselwe ukupholisa. Esimeni lapho izikulufu zixhunywe kwipuleti elibamba ukushisa kanye nendiza yaphansi ukuze kukhishwe ukushisa, ezinye izikulufu ezisetshenziselwa ukukhweza i-PCB zingaphinda zibe izindlela zokushisa ezisebenzayo eziya kusisekelo sesistimu. Uma kucatshangelwa umphumela wokuqhuba ukushisa nezindleko, inombolo yezikulufu kufanele ibe inani eliphakeme elifinyelela iphuzu lokuncipha kwembuyiselo. Ngemva kokuxhunywa ku-thermal conductive plate, i-metal PCB reinforcement plate inendawo yokupholisa eyengeziwe. Kwezinye izinhlelo zokusebenza lapho i-PCB imbozwe ngegobolondo, uhlobo olulawulwayo lokulungisa okokusebenza kunokusebenza okushisayo okuphakeme kunegobolondo elipholile emoyeni. Izixazululo zokupholisa, ezifana namafeni namasinki okushisa, nazo ziyizindlela ezivamile zokupholisa isistimu, kodwa ngokuvamile zidinga isikhala esiningi noma zidinga ukuguqula idizayini ukuze kuthuthukiswe umphumela wokupholisa.

Ukuklama isistimu ngokusebenza okushisayo okuphezulu, akwanele ukukhetha idivayisi ye-IC enhle nesixazululo esivaliwe. Ukusebenza kokukhipha ukushisa kwe-IC kuncike ku-PCB kanye nekhono lesistimu yokukhipha ukushisa ukupholisa ngokushesha amadivayisi e-IC. Ngokusebenzisa indlela yokupholisa engenhla, ukusebenza kokukhipha ukushisa kwesistimu kungathuthukiswa kakhulu.