- Chifukwa chiyani muyenera kupanga gulu?
Mapangidwe a PCB atapangidwa, SMT iyenera kukhazikitsidwa pamzere wa msonkhano kuti uziphatikiza. Malinga ndi zofunikira za Msonkhano wa SMT, fakitale iliyonse imatchulanso kukula koyenera. Mwachitsanzo, ngati kukula kwake ndi kochepa kwambiri kapena kwakukulu kwambiri, mawonekedwe ogwiritsira ntchito PCB pamzere wa msonkhano sungakonzeke.
Chifukwa chake ngati kukula kwa pcbu yathu yokha ndi yaying'ono kuposa kukula komwe kumatchulidwa ndi fakitale? Izi zikutanthauza kuti tikufunika kulumikiza mabatani a madera, mabwalo angapo ozungulira mu chidutswa chimodzi.both ya magetsi okwera kwambiri komanso ogulitsa mapulogalamu amatha kusintha kwambiri.
2.Panthul
1) Kukula kwake
A. Pofuna kuwongolera kukonza, zolimbitsa thupi za ma voids kapena njira ziyenera kukhala zachikuwa, nthawi zambiri kuzungulira φ hameter 5, mbale yaying'ono 5, mbale yaying'ono imatha kusintha.
B. PCB yokhala ndi kukula kwa bolodi yochepera 100mmm × 70mm isonkhana
2) mawonekedwe osakhazikika pa PCB
PCB yokhala ndi mawonekedwe osasinthika ndipo palibe gulu la panelo liyenera kuwonjezeredwa ndi Mzere Wovala Zida. Ngati pali dzenje pa PCB yoposa kapena yofanana ndi 5mm × 5mm, bowo liyenera kumalizidwa poyamba popewa kuwonongeka kwa mantraninging. Gawo lomalizidwa ndi gawo loyambirira la PCB liyenera kulumikizidwa ndi mfundo zingapo mbali imodzi ndikuchotsa ntchito yogulitsira.
Pomwe kulumikizana pakati pa chikho cham'manja ndi PCB ndi poyambira verove, mtunda pakati pa chipangizocho ndi porb ndi chida kapena dera.
3.Mgulu
Kuwongolera kwa gululi kudzapangidwa mogwirizana ndi kuwongolera kwa kufalikira kwa kufalikira, kupatula komwe kukula kwake sikungakuthandizeni kuti chiwerengero cha "v-chofiyira" kapena chocheperako.
Mwa bolodi yotchuka, samalani ndi kulumikizana pakati pa bolodi ndi sub-bolodi, yesani kulumikizana kwa gawo lililonse losiyanitsidwa pamzere.
4.Some zolemba za PCB
Pafupifupi, kupanga ma pcb kumachitika komwe kumatchedwa kuti kuphatikizidwa kwamphamvu kuti muwonjezere mawonekedwe a mzere wa SMT. Kodi ndi mfundo ziti zomwe ziyenera kusamala ndi msonkhano wa PCB? Chonde onani zomwe zili pansipa:
1) Chingwe chakunja (chophimba m'mphepete) cha PCB chimapangidwa mu lop yotsekedwa kuti muwonetsetse kuti pagawo la PCB silingasinthe mukakhazikika.
2) Kapangidwe ka PCB yomwe imafunikira kuti ikhale yoyandikira kwambiri, yolimbikitsidwa kugwiritsa ntchito 2 × 3, 3 × 3, ..........
3) M'lifupi mwake ≤260mm (mzere wa snimens) kapena ≤300mm (fuji pamzere). Ngati mukufuna kuyika zokhazokha, m'lifupi x kutalika ≤125mm × 180mm ya kukula kwake.
4) Bolo laling'ono lililonse pagawo la PCB likhala ndi mabowo osachepera atatu, 3≤ cere ≤ 6mm, lipt kapena smt sililoledwa mkati mwa 1mm.
5) Mtunda pakati pa bolodi yaying'onoyo iyenera kulamulidwa pakati pa 75mm ndi 145mm.
6) Pokhazikitsa dzenje lodziwika bwino, ndizofala kusiya malo otseguka 1.5mg yokulirapo kuzungulira dzenje.
7) Pasakhale zida zazikulu kapena zida zapamwamba pafupi ndi gawo pakati pa chimanga chakunja ndi gulu lamkati, komanso pakati pa gululo komanso gulu. Kupatula apo, payenera kukhala malo opitilira 0,5mm pakati pa zigawozo ndi m'mphepete mwa thabwa la PCB kuti muwonetsetse kuti chida chodula.
8) Mabowo anayi ogwiritsira ntchito mabowo anayi a 4mm ± 0.01m adatsegulidwa m'makona anayi a mkokomo a kunja kwa kapamwamba kakang'ono kameneka.
9) Mwakutero, QFP yokhala ndi ochepera 0,65mm iyenera kukhazikitsidwa mu gawo lake la diagonal.
10) Zigawo zikuluzikulu zidzakhala ndi zolemba kapena mabowo oyimitsa, monga ine / o / maickake, microswitch, mota, mota, etc.