Osewera ambiri a DIY apeza kuti mitundu ya PCB yomwe imagwiritsidwa ntchito ndi zinthu zosiyanasiyana pamsika ndiyowoneka bwino. Mitundu yodziwika bwino ya PCB ndi yakuda, yobiriwira, yabuluu, yachikasu, yofiirira, yofiira ndi yofiirira. Opanga ena apanga mwaluso ma PCB amitundu yosiyanasiyana monga oyera ndi pinki.

M'mawonekedwe achikhalidwe, PCB yakuda ikuwoneka kuti ili pamtunda, pomwe zofiira ndi zachikasu zimaperekedwa kumapeto otsika. Kodi izo si zoona?

PCB mkuwa wosanjikiza kuti si yokutidwa ndi solder chigoba mosavuta oxidized pamene mlengalenga

Tikudziwa kuti mbali zonse za PCB ndi zigawo zamkuwa. Popanga PCB, wosanjikiza wamkuwa adzapeza malo osalala komanso osatetezedwa mosasamala kanthu kuti amapangidwa ndi njira zowonjezera kapena zochepetsera.

Ngakhale kuti mankhwala a mkuwa sagwira ntchito ngati aluminiyamu, chitsulo, magnesium, ndi zina zotero, pamaso pa madzi, mkuwa wangwiro umakhudzidwa mosavuta ndi mpweya; chifukwa mpweya ndi nthunzi wa madzi umakhalapo mumlengalenga, pamwamba pa mkuwa wangwiro amawululidwa ndi mpweya Oxidation reaction idzachitika posachedwa.

Chifukwa makulidwe a mkuwa wosanjikiza mu PCB ndi woonda kwambiri, mkuwa wopangidwa ndi okosijeni udzakhala kondakitala woyipa wamagetsi, zomwe zingawononge kwambiri magwiridwe antchito amagetsi a PCB yonse.

Pofuna kupewa makutidwe ndi okosijeni amkuwa, kupatutsa magawo ogulitsidwa ndi osagulitsidwa a PCB panthawi ya soldering, komanso kuteteza pamwamba pa PCB, akatswiri adapanga zokutira zapadera. Mtundu uwu wa utoto ukhoza kugwiritsidwa ntchito mosavuta pamwamba pa PCB kuti ukhale wosanjikiza wotetezera ndi makulidwe ena ndikuletsa kukhudzana pakati pa mkuwa ndi mpweya. Chophimba ichi chimatchedwa solder mask, ndipo zinthu zomwe zimagwiritsidwa ntchito ndi solder mask.

Popeza imatchedwa lacquer, iyenera kukhala ndi mitundu yosiyanasiyana. Inde, chigoba choyambirira cha solder chikhoza kukhala chopanda mtundu komanso chowonekera, koma kuti zikhale zosavuta kukonza ndi kupanga, ma PCB nthawi zambiri amafunika kusindikizidwa ndi malemba ang'onoang'ono pa bolodi.

Transparent solder mask imatha kuwulula mtundu wakumbuyo wa PCB, kotero mawonekedwe ake siabwino mokwanira kaya akupanga, kukonza kapena kugulitsa. Chifukwa chake, mainjiniya adawonjezera mitundu yosiyanasiyana pachigoba cha solder kuti apange PCB yakuda, yofiira, kapena yabuluu.

PCB yakuda ndiyovuta kuwona, zomwe zimabweretsa zovuta pakukonza

Kuchokera pamalingaliro awa, mtundu wa PCB ulibe chochita ndi mtundu wa PCB. Kusiyana pakati pa PCB yakuda ndi ma PCB amitundu ina monga PCB yabuluu ndi PCB yachikasu ili mumtundu wa chigoba cha solder.

Ngati mapangidwe a PCB ndi njira yopangira ali ofanana ndendende, mtunduwo sudzakhala ndi zotsatirapo pa ntchito, komanso sudzakhala ndi zotsatira pa kutentha kutentha.

Ponena za PCB yakuda, chifukwa mawonekedwe omwe ali pamtunda amakhala pafupifupi ataphimbidwa, zimapangitsa kuti pakhale vuto lalikulu pakukonza pambuyo pake, chifukwa chake ndi mtundu womwe siwoyenera kupanga ndikugwiritsa ntchito.

Choncho, m'zaka zaposachedwapa, anthu pang'onopang'ono kusintha, kusiya ntchito wakuda solder chigoba, ndipo m'malo ntchito mdima wobiriwira, woderapo, mdima buluu ndi solder chigoba, cholinga ndi atsogolere kupanga ndi kukonza.

Atanena izi, aliyense wamvetsetsa vuto la mtundu wa PCB. Ponena za mawu akuti "chithunzi chamtundu kapena chotsika", ndichifukwa chakuti opanga amakonda kugwiritsa ntchito ma PCB akuda kuti apange zinthu zapamwamba, ndi zofiira, zabuluu, zobiriwira, ndi zachikasu kuti apange zinthu zochepa.

Chidule chake ndi chakuti: mankhwala amapereka tanthauzo la mtundu, osati mtundu umapereka tanthauzo la mankhwala.

Ubwino wogwiritsa ntchito zitsulo zamtengo wapatali monga golide ndi siliva pa PCB ndi chiyani?
Mtundu ndi womveka, tiyeni tikambirane za zitsulo zamtengo wapatali pa PCB! Opanga ena akamatsatsa malonda awo, amatchula mwachindunji kuti zinthu zawo zimagwiritsa ntchito njira zapadera monga plating golide ndi siliva plating. Ndiye kugwiritsa ntchito njirayi ndi chiyani?

The PCB pamwamba amafuna soldering zigawo zikuluzikulu, kotero mbali ya mkuwa wosanjikiza chofunika poyera kwa soldering. Zigawo zamkuwa zowonekerazi zimatchedwa pads. Mapadi nthawi zambiri amakhala amakona anayi kapena ozungulira okhala ndi malo ang'onoang'ono.

Pamwambapa, tikudziwa kuti mkuwa womwe umagwiritsidwa ntchito mu PCB umakhala wotsekemera mosavuta, choncho pambuyo pa mask solder, mkuwa pa pad umawonekera mlengalenga.

Ngati mkuwa pa pad ndi oxidized, sizidzakhala zovuta kugulitsa, komanso resistivity idzawonjezeka kwambiri, zomwe zidzakhudza kwambiri ntchito yomaliza. Chifukwa chake, mainjiniya adapanga njira zosiyanasiyana zotetezera mapadi. Mwachitsanzo, kuphimba ndi golide wachitsulo, kapena kuphimba pamwamba ndi siliva wosanjikiza pogwiritsa ntchito mankhwala, kapena kuphimba mkuwa ndi filimu yapadera ya mankhwala kuti muteteze kukhudzana pakati pa pedi ndi mpweya.

Kwa mapadi owonekera pa PCB, wosanjikiza wamkuwa amawonekera mwachindunji. Gawo ili liyenera kutetezedwa kuti lisakhale ndi okosijeni.

Kuchokera pamalingaliro awa, kaya ndi golidi kapena siliva, cholinga cha ndondomekoyi ndikuteteza oxidation, kuteteza pad, ndikuonetsetsa zokolola muzitsulo zotsatizana.

Komabe, kugwiritsa ntchito zitsulo zosiyanasiyana kudzakhazikitsa zofunikira pa nthawi yosungiramo ndi kusunga zinthu za PCB zomwe zimagwiritsidwa ntchito popanga. Choncho, mafakitale a PCB nthawi zambiri amagwiritsa ntchito makina opangira pulasitiki opanda mpweya kuti aziyika ma PCB pambuyo pomaliza kupanga PCB komanso asanapereke makasitomala kuonetsetsa kuti ma PCB alibe oxidized.

Pamaso pa zigawo ndi welded pa makina, wopanga khadi gulu ayeneranso kuona makutidwe ndi okosijeni digiri ya PCB, kuchotsa makutidwe ndi okosijeni PCB, ndi kuonetsetsa zokolola. Bungwe lomwe wogula womaliza amapeza ladutsa mayeso osiyanasiyana. Ngakhale pambuyo ntchito yaitali, makutidwe ndi okosijeni pafupifupi zidzangochitika pa pulagi-mu kugwirizana gawo, ndipo sadzakhala ndi zotsatira pa pedi ndi kale soldered zigawo zikuluzikulu.

Popeza kukana kwa siliva ndi golidi ndikotsika, mutagwiritsa ntchito zitsulo zapadera monga siliva ndi golidi, kodi kutentha kwa PCB kudzachepetsedwa?

Tikudziwa kuti chinthu chomwe chimakhudza kuchuluka kwa kutentha ndi kukana. Kukaniza kumagwirizana ndi zinthu za conductor palokha, malo ozungulira ndi kutalika kwa woyendetsa. Makulidwe azinthu zachitsulo pamtunda wa pedi ndi wocheperako kuposa 0.01 mm. Ngati padyo yakonzedwa ndi njira ya OST (organic protective film), sipadzakhala makulidwe owonjezera konse. Kukaniza komwe kumawonetsedwa ndi makulidwe ang'onoang'ono ndi pafupifupi ofanana ndi 0, ngakhale kosatheka kuwerengera, ndipo ndithudi sikungakhudze mbadwo wa kutentha.