Simbi Inosungirirwa yePCB: Gwaro Rekusarudza

Simbi yakanakisa yekusonerera paPCB inzvimbo inodzorwa nekupisa iri muhukuru hwe40–80 W ine tembiricha yakanaka yekudzoreredza kupisa, matipi madiki anochinjika, uye muromo wakadzika (wakachengeteka neESD). Wattage inoenderana nekuti simbi inodziyazve nekukurumidza sei mushure mekubata jointi, kwete kuti inopisa sei - uye tembiricha yakagadzikana uye inogadziriswa ndiyo inodzivirira mapedhi nezvinhu. Gwaro iri rinotsanangura chaizvo zvekutarisa, mhando dzesimbi dziripo, tembiricha yakakodzera uye muromo webasa remaseketi, uye nzira yekusonerera inogadzira majoini akachena, pamwe nepanowanikwa kusungirira nemaoko kune mukana wekubatanidza muchina.

Zvekutarisa musimbi inonamira pabasa rePCB

Mabhodhi ecircuit haaregereri: ma copper pads anoshanda se heat sinks, uye kupisa kwakawandisa kunosimudza ma pads kana kuuraya zvikamu zvinonzwa. Zvinhu zvakakosha pabasa rePCB ndezvekudzora nekuendesa kupisa , kwete simba rakagadzirwa.

Simbi yakachipa inodziya tembiricha isingadhuri inogona kushanda kune waya dzinoshandiswa nguva nenguva, asi paPCB chaiyo, simbi inodzorwa netembiricha ine kupora kwakanaka ndiyo inobvisa kushungurudzika kukuru uye njodzi kubhodhi rako.

Mhando dzesimbi dzinosungirirwa (uye mhando dzakakurumbira)

• Simbi yepenzura yekutanga — simbi ine simba rakagadzika isina kudzora tembiricha. Yakachipa, yakanaka pakubatanidza waya dzakaoma, asi sarudzo yakaipa pamabhodhi akapfava.
• Chiteshi chinodzorwa netembiricha — chikamu chepasi chine simbi uye tembiricha inogadziriswa. Kurudziro yakajairika yebasa rePCB. Mienzaniso inoshandiswa zvakanyanya inosanganisira Hakko FX-888D neFX-951, Weller WE1010, uye zviteshi zveJBC.
• Masimbi akangwara kana anotakurika — maaroni madiki anoshandisa USB-C kana DC ane simba rekudziisa nekukurumidza uye tembiricha inodzikiswa paruoko, akadai sePinecil neTS100/TS101. Akakodzera makit, kugadzirisa nzvimbo, uye mabhodhi madiki.
• Nzvimbo yekugadzirisa mhepo inopisa — inofefetera mhepo inopisa pane kubata joini; inoshandiswa pakugadzirisazve SMD neBGA, kubvisa nekutsiva zvikamu zvepadenga. Chinhu chinowedzera simbi, kwete chinotsiva.

Kune vanhu vazhinji vanovaka kana kugadzirisa mapuranga, chiteshi chinodzorwa nekupisa kwepakati pamwe nezvikamu zvidiki zvemazano zvinofukidza zvinenge zvese. Wedzera chiteshi chinodziya chete kana ukaita basa rekugadzirisa pamusoro pechidziro nguva dzose.

Kupisa kwakanyanya kwekunamira PCB

Isa simbi pamusoro penzvimbo inonyunguduka yesolder kuitira kuti kupisa kupfuure mujoinhi nekukurumidza — asi kwete zvakanyanya zvekuti unokuvadza bhodhi. Kurongeka kwakakodzera kunonyanya kuenderana nekuti unoshandisa solder ine lead kana kuti isina lead.

Chinangwa ndechekugadzira chisungo chimwe nechimwe mumasekonzi 1-3. Kana usingakwanise, wedzera tembiricha zvishoma kana kuti chinja kusvika pamucheto une huremu hwakawanda hwekupisa — kudzingirira kupisa nekusiya simbi iri pachisungo kwenguva refu ndiko kunopisa mapuranga.

Kusarudza muromo wekunamatira wakakodzera

Chimiro chemuromo chinokanganisa mhedzisiro kupfuura zvinotarisirwa nevakawanda vanotanga, nekuti muromo wacho ndiwo unopinza kupisa mujoini.

• Musoro wechisel — chiso chakati sandara, chakafara chinopfumisa kupisa zvinobudirira. Zano rakanakisisa rekushandisa paburi rinopinda nepakati uye kazhinji kacho rinoshandisa SMD; sarudza upamhi hwakaenzana nehukuru hwepad.
• Nzvimbo ine denderedzwa / pfumbu diki — nzvimbo yakapinza yenzvimbo dzakamanikana, dzakatetepa. Yakanyatsonaka asi inopfuudza kupisa kushoma, saka inononoka pamajoini makuru.
• Musoro webhevel / hove — chiso chakakombama chine denderedzwa diki resimbi; chakanakira mitsara yekudhonza-kusunga yemapini akapfava.

Kiti yakajairika chisero chimwe chete chakanaka chebasa rezuva nezuva, chidimbu chidiki chekona kuti chisvike zvakanaka, uye bevel yekusvetedza nekudhonza. Chengeta mativi akachena uye akabikwa mugaba — muromo wakasviba, usina kuiswa mugaba unomisa kupisa uye ndicho chikonzero chinowanzoitika chekuti simbi "isazonyungudutsa solder."

Maitiro ekusonesa PCB zvakanaka

Maitiro akanaka anokosha sesimbi. Chinongedzo chikuru cheburi:

1. Tin muromo — nyungudutsa kamuchina kadiki kekunamira pamucheto wakachena kuitira kuti kupisa kupfuure zvakanaka.
2. Pisai chisungo, kwete chinosungirirwa — bata muromo wepedhi uye chikamu chacho chibatanidzwe pamwe chete kwesekondi imwe chete.
3. Chinosungirirwa mujoini — Isa chinhu chinosungirirwa padheni rinopisa (kwete muromo) kuitira kuti chiyerere chakatenderedza jira ronyorovesa pamusoro pese.
4. Bvisa chinonamira, wobva wabvisa simbi — rega pfundo riite koni yakatsetseka uye inopenya. Fundo rakanaka rinoita segomo diki rinoputika, kwete bhora.
5. Usafambisa joini richitonhora, kana kuti rinogona kubuda rakaita sejecha (chinotonhora).

Kana muchida kuisa pamusoro pechinhu, tangai nepedhi rimwe chete, moisa chikamu chacho, mobatanidza pedhi iroro, mobva mabatanidza mapini asara — kuwedzera flux kunoita kuti basa rive nyore. Cheka maburi mushure mekusanganisa flux, mochenesa flux residues kana rudzi rweflux ruchida.

Zvikanganiso zvakajairika zvinokuvadza mabhodhi

• Kupisa kwakanyanya kwenguva yakareba — mapedhi anosimudza uye matrace. Shandisa tembiricha yakakodzera uye muromo wakakura, kwete kugara kwenguva refu.
• Chidimbu chakasviba, chisina kuiswa mugaba — inobvisa kupisa kushoma, zvichiita kuti majoini atonhore; chenesa uye gadzirisa marara nguva dzose.
• Kupisa solder panzvimbo pejoinhi — inoburitsa madomasi anogara pamusoro asinganyorove.
• Hapana kuyerera pakushanda kwakasanganiswa kana kuti kwakapfava — solder haingayerere; wedzera flux yemagetsi yakakodzera.
• Simbi isina kuvharwa paIC dzinonzwa — inogona kukanganisa ESD; shandisa simbi yakagayiwa isina njodzi yeESD.

Zvishongedzo zvinoita kuti PCB ive nyore kushandisa

Simbi iyi ingori chikamu chegadziriro inoshanda. Zvimwe zvinhu zvisingadhuri zvinoita mutsauko mukuru pamhedzisiro uye kuchengetedzeka:

• Solder — waya yakatetepa (0.5–0.8 mm) inoyerera-pakati; ine lead 60/40 kana 63/37 kuti zvive nyore, isina lead SAC305 kana zvichidikanwa.
• yerera — gel inoyerera musirinji isina kuchena yeSMD uye inogadziriswazve; inovandudza zvikuru kunyorova pabasa rakanyatsonaka.
• Kubvisa tambo yesolder uye/kana chikweshero chesolder — yekubvisa solder uye kugadzirisa mabhiriji.
• Mushonga wekuchenesa matipi — mushonga wekuchenesa wemvere dzemhangura (unonaka kusvika pamuromo) kana chipanji chakanyorova.
• Maoko ekubatsira / PCB holder — inosunungura maoko ese ari maviri uye mabhodhi madiki akasimba.
• Chinoburitsa furo kana kuti mhepo inofema zvakanaka — utsi hunobuda hunokonzera kusvotwa uye haufanirwe kufemedzwa.
• Isopropyl alcohol (IPA) uye bhurashi — yekuchenesa zvakasara zverosin uye yekuongorora majoini.

Nesimbi inodzorwa nekupisa, muromo wakakodzera, solder, flux, uye nzira yekubata bhodhi, chero prototype kana kugadzirisa zvinokwanisika.

Kana kusungirira nemaoko kusiri chishandiso chakakodzera

Simbi yakanaka yakakodzera kushandiswa pakugadzira zvinhu zvitsva, kugadzirisa, kamwe chete, uye kudzidza. Asi chishandiso chisiri icho kana bhodhi rava nezvikamu zvakawanda zvakapfava, majoini akavanzwa pasi peBGAs, kana kuti richida kuvakwa nehuwandu hwakaenzana, hunogona kuongororwa. Panguva iyoyo, kuunganidza muchina — paste yekusonesa yakadhindwa nestencil, pick-and-place, uye reflow — kunokurumidza uye kwakavimbika kupfuura simbi.

Highleap Electronics , kambani inogadzira PCB nePCBA iri kuChina, ndiyo inonyatsogadzirisa shanduko iyoyo. Kana prototype yako yakagadzirwa nemaoko yagadzirira kukura, SMT inounganidza uye PCBA inochinja-chinja bhodhi rese panguva imwe chete, neAOI neX-ray zvichiongorora majoini — kusanganisira majoini eBGA neQFN asina iron anogona kusvika. Ongororo yeDFM inoongorora kuti dhizaini yacho yagadzirira here isati yagadzirwa kekutanga.

Mashizha esimbi anosanganiswa nePCB

Ndeipi simba resimbi yekusonesa rakanakira basa rePCB?

40–80 W ine nzvimbo inodzorwa netembiricha. Wattage inodzora kuti muromo wemuchina unodzosa tembiricha yawo nekukurumidza sei mushure mekubata jointi; kuti kudzosa, kwete tembiricha yepamusoro, ndiko kunokosha kumajointi ePCB akachena.

Tembiricha ipi yandinofanira kuisa pakunamira bhodhi redunhu?

Anenge 315–370 °C (600–700 °F) ye lead solder uye 350–400 °C (660–750 °F) yeasina lead, uye dzimwe nguva majoini makuru anoda kusvika 425 °C. Chinangwa chekugadzira joini yega yega mumasekondi 1–3.

Ndinoda nzvimbo yekusonesa here kana kuti simbi yesimbi yakakwana here?

Kana paine waya dzemagetsi dzimwe nguva, simbi inoshanda. Pakushanda kwePCB — kunyanya SMD ne fine-pitch — nzvimbo inodzorwa tembiricha ine tembiricha yakanaka uye matipi anogona kuchinjwa anobatsira uye anodzivirira bhodhi rako.

Ndeipi muromo wekuputira wakanakira maPCB?

Musoro wechisel webasa rose nekuti chiso chayo chakati sandara chinopfumisa kupisa zvinobudirira; mupendero mutete wekona kuti pave nenzvimbo dzakasimba, dzakatetepa; uye mupendero mutete wepazasi/mahwanda wemitsara yepini inodhonzwa. Enzanisa upamhi hwemupendero nepedhi.

Sei simbi yangu yekusonesa isingazonyungudizve solder?

Kazhinji muromo wakasviba, wakasanganiswa neoxidized, usina kuiswa mugaba usingachatumiri kupisa. Geza nechinhu chinochenesa mvere dzemhangura kana chipanji chakanyorova wozoisazve mugaba mutsva; tsiva muromo wacho kana wakasakara zvakanyanya.

Ndingagona here kusanganisa zvikamu zveSMD nesimbi yakajairika?

Ehe kune zvikamu zvakawanda zveSMD, uchishandisa muromo mutete wobva wapfava: isa padhi rimwe chete, isa chikamu chacho, chibatanidze, wobva wasanganisa zvimwe zvese. Zvikamu zvakapfava kana kuti zveBGA zviri nani kuitwa nechiteshi chekugadzirisa mhepo inopisa kana nekubatanidza zvakare.

Ko solder ine lead kana isina lead iri nyore here kusona nemaoko?

Leaded (Sn63/Pb37) iri nyore — inonyunguduka pasi (183 °C) uye inonyorova zviri nyore. Hapana lead inodiwa kune zvigadzirwa zvakawanda zvekutengesa uye inoda tembiricha yakakwira zvishoma uye flux yakatarwa.

Ndingachengetedza sei muromo wangu wesimbi inonamirwa uri mumamiriro akanaka?

Gezai chipfundo chenyu chisati chasvika uye chapera nebrass wool kana chipanji chakanyorova, chichengetei mugaba nechinhu chitsva chinonamira pese pachinenge chisina kumira zvakanaka, uye musachipisa kupfuura zvinodiwa. Chipfundo chinonyatsochengetwa chinopfumisa kupisa zvakanaka uye chinogara kwenguva yakareba; hupenyu hwechipfundo hunodonha nekukurumidza kana chawedzera kuoxidation uye chinonamira chinomira kunamira.