Iyini i-PCB Back Drilling?
Inqubo yokubhola emuva kwe-PCB, okubuye kubizwe ngokuthi ukubhola ukujula okulawulwayo, ihlanganisa ukususa i-stub kuma-PCB anezingqimba eziningi ukuze udale i-vias. Inhloso yokubhoboza emuva iwukuba lula ukugeleza kwezimpawu phakathi kwezingqimba ezihlukene zebhodi ngaphandle kokuphazanyiswa okuvela kuma-stubs angafunwa.
Ukuze unikeze incazelo ecacile yenqubo yokumba emuva, ake sicabangele isibonelo.
Ake sithi kukhona i-PCB enezingqimba eziyi-12 enembobo ehlanganisa ungqimba lokuqala nolwe-12. Inhloso ukuxhuma kuphela isendlalelo sokuqala kungqimba lwe-9, kuyilapho kugcinwa izingqimba ze-10 kuya kwezingu-12 zingaxhumekile. Kodwa-ke, izendlalelo ezingaxhunyiwe zenza "ama-stubs" angaphazamisa indlela yesignali, okuholela ezinkingeni zobuqotho besignali. Ukubhola emuva kuhilela ukubhoboza lezi zinti ukusuka ohlangothini olungemuva lwebhodi ukuze kuthuthukiswe ukudluliswa kwesignali.
Iyini inhloso ye-PCB yokubhola emuva?
Ukubhola emuva kwe-PCB kusetshenziselwa ukususa ingxenye engasetshenzisiwe yembobo egqitshiwe (nge) edlulela ngale kongqimba lokugcina lwe-PCB. Le nqubo isiza ekunciphiseni izinkinga zesignali yobuqotho, njenge-stub resonance nokuboniswa kwesignali, okungenzeka kumiklamo yedijithali enesivinini esikhulu.
Iyini “i-aspect ratio”?
FAQ mayelana namabhodi esekethe aphrintiwe › TERMINOLOGY
Ubudlelwano phakathi kobubanzi bembobo nobude bayo. Uma umkhiqizi ethi umkhiqizo wabo “une-aspect ratio” engu-8:1 kusho, isibonelo, ukuthi ububanzi bembobo bungu-0.20 mm ku-PCB engu-1.60 mm obukhulu.
Ezakhiweni ze-HDI, i-aspect ratio ye-microvia ikhawulelwe ku-1:1, kodwa i-0.7-0.8:1 ikhethwa ukuze kube lula ukucwenga.
Yiziphi izinzuzo PCB emuva drilling?
Izinzuzo zokubhola emuva kwe-PCB zifaka ubuqotho besignali obuthuthukisiwe, ukulahlekelwa okuncishisiwe kokufaka, ukulawula okuthuthukisiwe kwe-crosstalk, kanye nomkhawulokudonsa okhulisiwe. Ngokususa ingxenye engasetshenziswanga yombhobho, ukubhola emuva kunciphisa ukuzwakala kwe-stub resonance kanye nokuboniswa kwesignali, okuholela ekudluliseni isignali okuhlanzekile nokunembe kakhudlwana.