Chii chinonzi PCB Back Drilling?
Maitiro ekuchera kumashure kwePCB, anonziwo kucherwa kwakadzika kwakadzorwa, anosanganisira kubvisa stub mumaPCB ane layer akawanda kuti pagadzirwe mavias. Chinangwa chekuchera kumashure ndechekurerutsa kufamba kwezviratidzo pakati pezvikamu zvakasiyana zvebhodhi pasina kukanganiswa nezvidimbu zvisingadiwe.
Kuti titsanangure zvakajeka maitiro ekuboorera kumashure, ngatifungei nezvemuenzaniso.
Ngatitii pane PCB ine zvidimbu gumi nezviviri ine gomba rinopinda rinobatanidza zvidimbu zvekutanga nezvegumi nezviviri. Chinangwa ndechekubatanidza zvidimbu zvekutanga chete kune zvidimbu zvepfumbamwe, ukuwo zvidimbu zvegumi kusvika kune gumi nezviviri zvichiramba zvisina kubatana. Zvisinei, zvidimbu zvisina kubatana zvinogadzira "zvidimbu" zvinogona kukanganisa nzira yezviratidzo, zvichikonzera matambudziko ekuvimbika kwezviratidzo. Kuboora kumashure kunosanganisira kuboora zvidimbu izvi kubva kudivi rekumashure rebhodhi kuti uvandudze kutapurirana kwezviratidzo.
Chinangwa chePCB back drilling chii?
Kuboorera PCB kumashure kunoshandiswa kubvisa chikamu chisina kushandiswa chegomba rakaputirwa (kuburikidza) rinodarika chikamu chekupedzisira chePCB. Maitiro aya anobatsira kuderedza matambudziko ekuvimbika kwechiratidzo, akadai se stub resonance uye signal reflections, izvo zvinogona kuitika mumadhizaini edhijitari anomhanya kwazvo.
Chii chinonzi "aspect ratio"?
Mibvunzo Inowanzo bvunzwa nezve mabhodhi edunhu akadhindwa › TERMINOLOGY
Hukama huripo pakati pedhayamita yegomba nehurefu hwaro. Kana mugadziri akataura kuti kugadzirwa kwavo kune "aspect ratio" ye8:1 zvinoreva, semuenzaniso, kuti dhayamita yegomba i0.20 mm muPCB ine ukobvu hwe1.60 mm.
Kune HDI structures, aspect ratio ye microvia inogumira pa 1:1, asi 0.7-0.8:1 ndiyo inonyanya kukosha pane nyore kuisa plating.
Ndezvipi zvakanakira kuchera PCB kumashure?
Mabhenefiti ePCB back drilling anosanganisira kuvandudzwa kwekuvimbika kwesignali, kudzikira kwekuiswa, kuwedzera kudzora crosstalk, uye kuwedzera bandwidth. Nekubvisa chikamu chisina kushandiswa che via barrel, back drilling inoderedza stub resonance uye signal reflections, zvichiita kuti signal transmission ive yakachena uye yakarurama.