Ngokuklama kwembobo ye-HDI PCB
Ekwakhiweni kwe-PCB enesivinini esikhulu, i-PCB enezingqimba eziningi ivamise ukusetshenziswa, futhi ngembobo iyisici esibalulekile ekwakhiweni kwe-PCB enezingqimba eziningi. Imbobo edlula ku-PCB yakhiwe izingxenye ezintathu: imbobo, indawo yephedi yokushisela ezungeze umgodi kanye nendawo yokuhlukanisa ungqimba WAMANDLA. Okulandelayo, sizoqonda i-PCB enesivinini esikhulu ngenkinga yembobo kanye nezidingo zokuklama.
Umthelela wokungena ngembobo ku-HDI PCB
Kubhodi lezendlalelo eziningi ze-HDI PCB, ukuxhumana phakathi kongqimba olulodwa nolunye ungqimba kudinga ukuxhunywa ngezimbobo. Uma imvamisa ingaphansi kuka-1 GHz, izimbobo zingadlala indima enhle ekuxhumekeni, futhi amandla e-parasitic kanye ne-inductance ingashaywa indiva. Uma i-frequency ingaphezu kuka-1 GHz, umphumela womphumela we-parasitic wembobo engaphezulu kubuqotho besignali awukwazi ukuzitshwa. Kuleli qophelo, imbobo engaphezulu iveza ukunqamuka okungaqhubeki kwe-impedance endleleni yokudlulisela, okuzoholela ekubonakalisweni kwesignali, ukubambezeleka, ukuncishiswa nezinye izinkinga zesignali yobuqotho.
Lapho isignali idluliselwa kwesinye isendlalelo ngembobo, ungqimba lwereferensi lomugqa wesiginali lusebenza njengendlela yokubuya yesiginali ngembobo, futhi ukubuya kwamanje kuzogeleza phakathi kwezingqimba zereferensi ngokusebenzisa i-capacitive coupling, okubangela amabhomu aphansi futhi ezinye izinkinga.
Uhlobo lweThoba-Hole, Ngokujwayelekile, ngembobo ihlukaniswe izigaba ezintathu: ngembobo, imbobo eyimpumputhe kanye nembobo egqitshiwe.
Imbobo eyimpumputhe: imbobo etholakala phezulu nangaphansi kwebhodi lesifunda eliphrintiwe, elinokujula okuthile kokuxhumana phakathi komugqa ongaphezulu kanye nomugqa wangaphakathi ongaphansi. Ukujula komgodi ngokuvamile akudluli isilinganiso esithile sokuvula.
Imbobo engcwatshiwe: imbobo yokuxhuma engxenyeni yangaphakathi yebhodi lesifunda ephrintiwe engadluleli ebusweni bebhodi lesifunda.
Ngembobo: le mbobo idlula kulo lonke ibhodi lesifunda futhi ingasetshenziselwa ukuxhumana kwangaphakathi noma njengembobo yokubeka ekhuphukayo yezingxenye. Ngenxa yokuthi imbobo yenqubo kulula ukuyifinyelela, izindleko ziphansi, ngakho-ke kusetshenziswa ibhodi lesifunda eliphrintiwe
Ngokusebenzisa imbobo design in high speed PCB
Ekwakhiweni kwe-PCB enesivinini esikhulu, imbobo ye-VIA ebonakala ilula ngokuvamile izoletha imiphumela emibi kakhulu ekwakhiweni kwesekethe.Ukuze kwehliswe imiphumela emibi ebangelwa umphumela we-parasitic wokubhoboza, singazama konke okusemandleni ethu uku:
(1) khetha usayizi wembobo ozwakalayo.Ngomklamo we-PCB onokuminyana okuvamile kwezendlalelo eziningi, kungcono ukhethe u-0.25mm/0.51mm/0.91mm (imbobo yokubhoboza/iphedi yokushisela/Indawo yokuhlukanisa AMANDLA) ngembobo. Ubukhulu be-PCB bungakwazi futhi ukusebenzisa u-0.20mm/0.46mm/0.86mm ngembobo, futhi ingazama imbobo engadluli;Ngokunikezwa kwamandla noma imbobo yocingo ephansi ingabhekwa njengokusebenzisa usayizi omkhulu ukuze kuncishiswe i-impedance;
(2) uma ikhudlwana indawo yokuhlukanisa AMANDLA, iba ngcono. Uma kucatshangelwa ukuminyana kwembobo ku-PCB, ngokuvamile kungu-D1=D2+0.41;
(3) zama ukungashintshi ungqimba lwesignali ku-PCB, okungukuthi, zama ukunciphisa imbobo;
(4) ukusetshenziswa kwe-PCB ezacile kusiza ekunciphiseni amapharamitha amabili ezinambuzane ngembobo;
(5) iphinikhodi yokuphakelwa kukagesi nomhlabathi kufanele kube seduze nomgodi. Ukunciphisa ukuhola phakathi kwembobo nephini, kungcono, ngoba kuzoholela ekwandeni kwe-inductance.Ngasikhathi sinye, ukunikezwa kwamandla kanye nokuhola komhlabathi kufanele kube okukhulu ngangokunokwenzeka ukuze kuncishiswe i-impedance;
(6) beka amaphasi athile eduze nezimbobo zokudlula zesendlalelo sokushintshisana kwesignali ukuze unikeze iluphu yebanga elifushane yesiginali.
Ngaphezu kwalokho, ngobude bembobo nakho kungenye yezinto eziyinhloko ezithinta ngokusebenzisa imbobo inductance.Ngomgodi wokudlula phezulu naphansi, ubude bembobo yokudlula bulingana nobukhulu be-PCB. Ngenxa yenani elikhulayo lezendlalelo ze-PCB, ukujiya kwe-PCB kuvame ukufinyelela ngaphezu kuka-5 mm.
Kodwa-ke, ekwakhiweni kwe-PCB enesivinini esikhulu, ukuze kuncishiswe inkinga ebangelwa imbobo, ubude bembobo ngokuvamile bulawulwa ngaphakathi kuka-2.0mm.Ngobude bembobo obukhulu kuno-2.0mm, ukuqhubeka kwe-impedance yembobo kungathuthukiswa kwabanye. Lapho ubude bembobo buyi-1.0mm nangaphansi, indawo ekahle yokuvula imbobo ingu-0.20mm ~ 0.30mm.