pambuyo pa PCB kupanga kumalizidwa, zonse zikhala bwino? Ndipotu izi sizili choncho. M’kati mwa PCB processing, mavuto osiyanasiyana nthawi zambiri amakumana, monga malata mosalekeza pambuyo soldering yoweyula. Inde, si mavuto onse omwe ali “mphika” wa mapangidwe a PCB, koma monga okonza, choyamba tiyenera kuonetsetsa kuti mapangidwe athu ndi aulere.

Zakumapeto

Wave soldering

Wave soldering ndi kupanga soldering pamwamba pa pulagi-mu bolodi mwachindunji kukhudzana mkulu kutentha madzi malata kukwaniritsa cholinga soldering. Tini yamadzi otentha kwambiri imakhala ndi malo otsetsereka, ndipo chipangizo chapadera chimapangitsa tini lamadzimadzi kukhala chinthu chofanana ndi mafunde, choncho amatchedwa “wave soldering”. Chinthu chachikulu ndi mipiringidzo ya solder.

Chifukwa chiyani bolodi la PCB limawoneka ndi malata pambuyo powotchera mafunde? Kodi mungapewe bwanji?

Wave soldering ndondomeko

Malumikizidwe awiri kapena kupitilira apo amalumikizidwa ndi solder, zomwe zimapangitsa kuti pakhale mawonekedwe osawoneka bwino komanso magwiridwe antchito, omwe amafotokozedwa ngati gawo lachilema ndi IPC-A-610D.

Chifukwa chiyani bolodi la PCB limawoneka ndi malata pambuyo powotchera mafunde?

Choyamba, tiyenera kufotokoza momveka bwino kuti kukhalapo kwa malata pa bolodi PCB si vuto la osauka PCB kamangidwe. Zitha kukhalanso chifukwa cha kusayenda bwino, kunyowa kosakwanira, kugwiritsa ntchito kosagwirizana, kutentha kwa preheating ndi kutentha kwa solder panthawi ya soldering. Zabwino kudikirira chifukwa.

Ngati ndi vuto la mapangidwe a PCB, titha kuganizira izi:

1. Kaya mtunda wapakati pa zolumikizira za solder za chipangizo cholumikizira ndi chokwanira;

2. Kodi njira yotumizira plug-in ndiyoyenera?

3. Ngati phula silikukwaniritsa zofunikira za ndondomekoyi, kodi pali cholembera chobera malata ndi inki ya silk screen?

4. Kaya kutalika kwa ma plug-in ndiatali kwambiri, etc.

Kodi mungapewe bwanji ngakhale malata pamapangidwe a PCB?

1. Sankhani zigawo zoyenera. Ngati bolodi ikufunika kutenthetsa, malo omwe akulimbikitsidwa kuti agwiritsidwe ntchito (malo apakati pakati pa ma PIN) ndi aakulu kuposa 2.54mm, ndipo akulimbikitsidwa kuti apitirire 2.0mm, apo ayi chiwopsezo cha kugwirizana kwa malata ndichokwera kwambiri. Apa mutha kusintha moyenerera pad wokometsedwa kuti mukumane ndi ukadaulo wokonza ndikupewa kulumikizana ndi malata.

2. Musalowetse phazi la soldering kupitirira 2mm, mwinamwake ndikosavuta kwambiri kulumikiza malata. Phindu lamphamvu, pamene kutalika kwa kutsogolera kunja kwa bolodi ndi ≤1mm, mwayi wolumikiza malata a soketi ya pini udzachepetsedwa kwambiri.

3. Mtunda pakati pa mphete zamkuwa uyenera kukhala wosachepera 0.5mm, ndipo mafuta oyera ayenera kuwonjezeredwa pakati pa mphete zamkuwa. Ichi ndichifukwa chake nthawi zambiri timayika mafuta oyera a silkscreen pamwamba pa plug-in popanga. Panthawi yokonza, pamene pad imatsegulidwa m’dera la solder mask, samalani kuti musapewe mafuta oyera pawindo la silika.

4. Mlatho wobiriwira wamafuta uyenera kukhala wosachepera 2mil (kupatulapo tchipisi tating’onoting’ono tokhala ndi pini monga mapaketi a QFP), apo ayi ndizosavuta kuyambitsa kulumikizana kwa malata pakati pa mapepalawo pakukonza.

5. Kutalika kwa zigawozo kumagwirizana ndi kayendetsedwe ka kayendedwe ka bolodi mu njanji, kotero chiwerengero cha zikhomo zogwiritsira ntchito kugwirizana kwa tini zidzachepetsedwa kwambiri. Muukadaulo waukadaulo wa PCB, kapangidwe kake kamatsimikizira kupanga, motero njira yotumizira ndikuyika zida zowotchera mafunde ndizosangalatsa.

6. Onjezani mapepala akuba a malata, onjezani mapepala akuba a malata kumapeto kwa njira yotumizira malinga ndi zofunikira za pulagi pa bolodi. Kukula kwa thabwa lobera malata kungasinthidwe moyenera molingana ndi kachulukidwe ka bolodi.

7. Ngati mukuyenera kugwiritsa ntchito plug-in yowonjezereka, tikhoza kukhazikitsa chidutswa cha solder drag pa malo apamwamba a tini kuti muteteze phala la solder kuti lipangidwe ndikupangitsa kuti chigawo cha mapazi chigwirizane ndi malata.