Izindinganiso ze-PCB flatness zibaluleke kakhulu ekusebenzeni okuhle. Umnsalo nokusonta izindlela ibhodi lesifunda eliphrintiwe elingagoba ngazo. Umnsalo yilapho ibhodi ligoba ngobude balo. I-twist yilapho amakhona esezindaweni eziphakeme ezihlukene. Lezi zinkinga zingenza umhlangano ube nzima futhi ulimaze ukuthi i-pcb isebenza kanjani. Izindinganiso ze-IPC-6011 zithi amasekhethi kufanele alinganisele futhi akhe ngokufana nhlangothi zombili. Lokhu kusiza ukumisa umnsalo nokusonta. Uma izisindo zethusi ziyi-3 oz/ft² noma ngaphezulu, kudingeka imithetho eqinile. Ukulawulwa kwe-flatness kugcina i-pcb iqinile futhi imisa isidingo sezingxenye ezengeziwe zokusekela.
I-Bow and twist shintsha indlela i-pcb eyisicaba futhi unqume ukuthi ibhodi lesifunda eliphrintiwe lizodlula imithetho eqinile yezimboni.
Izitoreji Eziyinhloko
I-Bow and twist yenza ama-PCB agobe, okungalimaza indlela asebenza ngayo. Kubalulekile ukulawula umnsalo nokusonta. - Ukusebenzisa amathuluzi e-IPC-TM-650 kuhlola ukugcwala kusenesikhathi. Lokhu kusiza ukuthola izinkinga ngokushesha futhi kuqinisekisa ukuthi amabhodi alandela imithetho. - Ukwenza ama-PCB ngethusi ngisho nezingxenye ezihlakaniphile kusiza ukumisa umnsalo nokusonteka lapho uwenza. - Ukukhetha izinto ezinhle kanye nogqinsi olufanele kugcina ama-PCB eqinile. Lokhu kuwenza abe mancane amathuba okuthi agobe ekushiseni noma emanzini. - Ukukhuluma kahle phakathi kwabakhi namakhasimende kusiza ukulungisa izinkinga ngokushesha futhi kwenza ama-PCB abe ngcono.
PCB Flatness Amazinga
Bow and Twist
I-PCB flatness isho ukuthi bushelelezi kangakanani ngisho nebhodi. I-Bow and twist yizindlela eziyinhloko ibhodi elingalahlekelwa ngayo flatness. Umnsalo wenzeka lapho wonke amakhona omane ethinta itafula, kodwa eliphakathi liyaphakama. I-twist yilapho kuthinta khona amakhona amathathu, kodwa ikhona elilodwa liphakeme noma liphansi. Lezi zinkinga zingabonakala ngesikhathi sokwenza ibhodi, ikakhulukazi ngemva kwezinyathelo zokushisa. Umnsalo ungaba ngu-0.47 mm, futhi ushintsha ngezinto zebhodi nokushisa. I-twist yilapho ibhodi lijika lihambisana ne-diagonal yalo, ngakho ikhona elilodwa liphezulu noma phansi.
Umnsalo nokusonta akulandeli iphethini evamile. Izinto ezihlukene kanye nokushisa ngesikhathi se-soldering kubangela lezi zinguquko. Abantu basebenzisa izindlela ezikhethekile ukuhlola umnsalo nokusonta. Babheka ibhodi, basebenzisa amathuluzi okucaba, futhi ngezinye izikhathi ukuskena kwe-3D. Imithetho efana ne-IPC-TM-650 2.4.22 ichaza ukuthi ulinganisa kanjani futhi wamukele amabhodi omnsalo nokusonteka.
Ithebula elingezansi libonisa umnsalo nokusonta okuningi okuvunyelwe ohlotsheni lwebhodi ngalinye:
Uhlobo Lwebhodi | Ubuningi Bow and Twist (%) |
|---|---|
Ngamadivayisi e-Surface Mount | 0.75% |
Ngaphandle kwe-SMD | 1.5% |
Le mikhawulo ivela ku-IPC 2422-1 kanye nemithetho ye-IPC 2422-2. Baqinisekisa ukuthi amabhodi asebenza kahle, ngisho noma egoba kancane.
Kungani I-Flatness Ibalulekile
I-flatness ibaluleke kakhulu ukuthi i-pcb isebenza kahle kangakanani. Umnsalo nokusonta kungenza kube nzima ukubeka izingxenye ebhodini. Uma ibhodi lingekho flat, izingxenye zingase zingalingani kahle, futhi i-solder ingase inganamatheli kahle. Lokhu kungabangela amasekhethi avulekile noma izindawo ezibuthakathaka.
Ucwaningo lubonisa ama-pcbs ayisicaba ahlala isikhathi eside futhi asebenza kangcono. Umnsalo omningi noma i-twist ibeka ingcindezi emalungeni e-solder. Ukuthi ulibophela kanjani ibhodi, njengalapho ubeka khona amabhawodi, lishintsha ukuthi ligoba kangakanani. Ama-bolts akude nezingxenye ezibalulekile asiza amalunga e-solder ukuthi ahlale isikhathi eside. Uma ama-bolt ajoyina i-pcb ezintweni ezikhula ngokuhlukile ngokushisa, amalunga e-solder angaphuka aze afike ku-60% maduze. Ukuhlolwa namamodeli wekhompiyutha abonisa ukuthi izinhlelo zokusekela ziyashintsha lapho ukuqhekeka kuqala khona nokuthi amajoyinti e-solder ahlala isikhathi esingakanani.
Abacwaningi bathola ukuthi ama-pcbs ayisicaba anikeza imiphumela engcono ekwenzeni amabhodi. Amabhodi ane-coplanarity encane anezinkinga ezimbalwa ze-solder. Isibonelo, ku-0.177 mm coplanarity, ithuba lokuvula i-solder cishe li-1%. Amabhodi aphumelela izivivinyo ngokuvamile athambile kunalawo angaphumeleli. Lapho ibhodi lihlala phezu kwephaneli nokuthi liphuka kanjani nakho kubalulekile, kodwa ibhalansi yethusi nezinto ezibonakalayo azishintshi izinto kakhulu.
Ukulawula umnsalo nokusonta akukhona nje ukulandela imithetho. Isiza wonke amabhodi wesifunda aphrintiwe ukuthi asebenze kahle futhi ahlale isikhathi eside empilweni yangempela.
Izindlela Zokukala
IPC-TM-650
Onjiniyela basebenzisa izindlela ezahlukene ukuhlola ukuthi ibhodi lesifunda eliphrintiwe liyisicaba kanjani. Izinga le-IPC-TM-650 lichaza indlela yokuhlola umnsalo nokusonta. Ukuze wenze lokhu, ubeka ibhodi endaweni eyisicaba. Bese ukala izindawo eziphakeme neziphansi kakhulu. Abantu basebenzisa amathuluzi noma amakhamera akhethekile kulokhu. Amanye amathuluzi avamile i-shadow moiré, i-fringe projection, ne-confocal measurement. Lawa mathuluzi angathola izinguquko ezincane kakhulu zobude, ngezinye izikhathi zibe zincane njengama-micrometer angu-5. Abanye abaklami bafuna amasheke anembe nakakhulu, njenge-micrometer engu-1 noma 3.
Ukukala flatness, kufanele ulandele izinyathelo ezithile:
Bhaka ibhodi kuqala ukuze ususe amanzi.
Penda ibhodi libe mhlophe ukuze amakhamera abone kangcono.
Sika ibhodi ukuze lingene kuhhavini.
Beka ama-thermocouple eduze, kodwa hhayi phakathi, indawo yokuhlola.
Sebenzisa ukushisa okukhuphuka kancane, phakathi kuka-0.5°C no-1.0°C umzuzwana ngamunye.
Izinga le-IPC-TM-650 liphinde lithi ukuhlola amaphaneli amakhulu ngaphambi kokuwasika emabhodini amancane. Lokhu kuqinisekisa ukuthi wonke amabhodi mahle ngaphambi kokuwahlanganisa.
Imikhawulo Eyamukelekayo
Kunemithetho ecacile yokuthi ibhodi kufanele libe flat kanjani. Izinombolo ezifanele zincike ekutheni luhlobo luni lwebhodi nokuthi lizosetshenziswa kanjani. Ithebula elingezansi libonisa imikhawulo eyinhloko:
Uhlobo Lwebhodi | I-Bow and Twist Limit (%) |
|---|---|
Amabhodi esekethe aphrintiwe afakwe phezulu | 0.75 |
Ezinye izinhlobo zamabhodi | 1.5 |
Amabhodi kufanele futhi abe ukujiya okulungile futhi abe nemiphetho ebushelelezi. Uma ibhodi lijiyile kune-31 mils, kufanele libe phakathi kuka-±10% wogqinsi olulungile. Amabhodi azacile angavalwa kuphela ngo-±3 mils. Uma ibhodi ligoba ngaphezu kuka-0.75%, akulungile emisebenzini eminingi. Le mithetho isiza ukuqinisekisa ukuthi amabhodi asebenza kahle lapho enziwa futhi esetshenziswa.
Ngokulandela lezi zivivinyo ze-bow and twist, izinkampani zingenza amabhodi ahlangabezana nemithetho futhi angahluleki kangako.
Izinto Ezithinta I-PCB Flatness
Idizayini nokuhlelwa
Ukuthi uyiklama kanjani futhi uyibeke kanjani i-pcb ishintsha indlela ehlala ngayo. Onjiniyela bazama ukugcina ithusi ngisho nhlangothi zombili. Uma uhlangothi olulodwa lunethusi eliningi, ibhodi lingagoba. Lokhu kwenzeka lapho ibhodi liphola. Ukunqwabelana okulinganiselwe kusiza ukumisa le nkinga. Imikhondo nezindiza zibekwe ukusabalalisa ukucindezeleka. Ukusika okukhulu noma izikhala kungenza izindawo ezibuthakathaka. Lawa machashazi abuthakathaka enza umnsalo noma ukusonteka kube nokwenzeka kakhulu phakathi ne-lamination. Lapho ubeka khona izingxenye nezimbobo nakho kubalulekile. Izinketho ezinhle kumklamo zisiza ukuyeka ukugoba. Lokhu kwenza i-pcb isebenze kangcono futhi ihlale isikhathi eside.
Ithiphu: Ukugcina ithusi lilingana nokubeka izingxenye ezindaweni ezihlakaniphile kusiza ukumisa ukugoba nokusonteka uma ukwenza ibhodi lesifunda.
Izinto kanye Nokuqina
Izinto zokwakha kanye nogqinsi ozikhethayo zinquma ukuthi i-pcb izoba isicaba kanjani. Izinto ezihlukene zisebenza ngokuhlukile ngokushisa namanzi. I-FR4, i-Teflon, nama-substrates avumelana nezimo ngayinye inezici ezikhethekile. I-FR4 ine-CTE ephakathi, kodwa i-CTE ye-Teflon iphakeme kakhulu. Ama-substrates aguqukayo adinga ukunakekelwa okwengeziwe ukuze ahlale flat. Lapho lezi zinto zishisa ngesikhathi sokuqhakaza, ziyakhula futhi zishwabane ngesivinini esihlukile. Lokhu kungenza ibhodi ligobe noma lisonte.
Ukuthi ibhodi liwugqinsi kangakanani nakho kubaluleke kakhulu. Amabhodi azacile ayagoba noma asonte kalula. Amabhodi awugqinsi awagobi kakhulu kodwa angaba lukhuni kakhulu. Ithebula elingezansi libonisa ukuthi impahla kanye nogqinsi kushintsha kanjani ukucaba nokubekezelelana:
Ipharamitha | Incazelo | Umthelela ku-PCB Flatness nokubekezelelana |
|---|---|---|
Uhlobo Material | FR4, Teflon, Flexible Substrates | Ama-CTE ahlukene enza amabhodi asonte noma ashwabane; I-Teflon inzima kakhulu ukuyigcina isicaba, ama-substrates aguquguqukayo adinga ukunakekelwa okukhethekile |
Ibanga Lokuqina (mm) | 0.2-0.4 | ±0.1mm ukubekezelelana; amabhodi awugqinsi alahlekelwa ukuguquguquka, amancane abuthakathaka |
Ibanga Lokuqina (mm) | 0.5-1.0 | ±0.2mm ukubekezelelana; amabhodi awugqinsi anciphisa amasignali anesivinini esikhulu, azacile awazinzi |
Ibanga Lokuqina (mm) | 1.0-1.5 | ± 0.3mm ukubekezelelana; amabhodi awugqinsi anzima ukukhwezwa, azacile angaphuka |
I-Thermal Expansion Effects | FR4 (14-16 ppm/°C), Teflon (30-40 ppm/°C), Polyimide (10-20 ppm/°C) | I-CTE ephakeme isho ukuwohloka okwengeziwe, okulimaza ukucaba |
Izingosi zemvelo | Izinga lokushisa, Umswakama | Ukushisa namanzi kwenza amabhodi akhule, ashwabane, noma asonte |
Izinqubo Zokukhiqiza | Gcwalisa kabusha ingcindezi yokushisa eshisayo | Ukupholisa okungalingani kugoba amabhodi futhi kuhambisa izingxenye |
Onjiniyela bakhetha izinto zokwakha kanye nogqinsi ngokusekelwe kulokho okudingwa yi-pcb. Baphinde bacabange ukuthi lezi zinketho zishintsha kanjani umnsalo nokusonteka ngesikhathi sokwenza nokusebenzisa ibhodi.
Ukubala Kwesendlalelo
Inani lezendlalelo ku-pcb lishintsha ukuthi ligoba kangakanani. Izendlalelo ezengeziwe zisho izinyathelo ezengeziwe zokucwasa. Isinyathelo ngasinye sisebenzisa ukushisa nokucindezela. Lezi zinyathelo zingenza ibhodi ligobe noma lisonte uma lingalingani. Izendlalelo ezengeziwe zingasho ingcindezi eyengeziwe. Uma izendlalelo zingewona ukushuba okufanayo noma uhlobo, ibhodi lingagoba ngemuva kokulahlwa.
Abaklami basebenzisa ngisho nokunqwabelanisa ukuze basize ngalokhu. Aqondanisa izingqimba ngenhla nangezansi phakathi nendawo. Lokhu kugcina ibhodi liphansi ngesikhathi sokwenza. Uma i-stack-up ingekho, ibhodi lingakwazi ukugoba ngesikhathi se-lamination. Ukuhlela inani lezendlalelo nokupakisha kusiza ukumisa umnsalo nokusonta.
Ukukhiqiza Process
Indlela i-pcb eyenziwe ngayo ishintsha indlela eyisicaba ngayo ekugcineni. Zonke izinyathelo, njenge-lamination ne-soldering, zingabangela izinkinga. I-Lamination isebenzisa ukushisa nokucindezela ukuhlanganisa izingqimba. Uma ukushisa noma ukucindezela kungekho, ibhodi lingagoba. Ukupholisa okungekho ngisho nangemva kokuba i-lamination nayo ibangele ukugoba. Ngesikhathi se-reflow soldering, ibhodi liyashisa futhi. Lokhu kushisa kungenza ibhodi ligobe, ikakhulukazi uma izinto zikhula ngamanani ahlukene.
Abakhiqizi basebenzisa izinyathelo ezicophelelayo ukumisa lezi zinkinga. Babuka ukushisa nokucindezela ngesikhathi sokulanyiswa. Babhaka amabhodi ngaphambi kokuwahlanganisa ukuze bawomise. Lezi zinyathelo zisiza ukumisa umnsalo nokusonta. Amaqembu ahlola flatness izikhathi eziningi ngesikhathi enza. Ukuhlola kwangaphambi kwesikhathi kuthola izinkinga ngaphambi kwesinyathelo esilandelayo. Ukulawula okuhle kwenqubo kugcina i-pcb flat futhi yehlisa amathuba ezinkinga.
Qaphela: Ukugcina inqubo ingashintshi ngesikhathi sokwenza kanye ne-lamination kubaluleke kakhulu ukumisa umnsalo nokusonta kuwo wonke ama-pcb.
Ukuqinisekisa Ukuthobelana kwe-PCB
Ukwenza Okungcono
Abakhiqizi basebenzisa izindlela ezahlukene zokugcina i-pcb flatness. Bayakhetha i-surface iphela njenge-ENIG noma ENEPIG. Lezi ziqephu zisiza amaphedi ukuthi ahlale elingana futhi eqinile. Imaski eyomile ye-solder yefilimu ingenza amabhodi abe flat kakhulu, afinyelele kuma-micrometer angu-5-7. Onjiniyela baklama izitaki ezifanayo nhlangothi zombili. Babhalansisa ithusi ukumisa umnsalo nokusonta. Izindawo zethusi ezingenalutho ziyagcwala ukuze kuqhubeke ukucwebezela ngokulinganayo. Ngesikhathi se-lamination, babuka ukushisa nokucindezela ukuze bayeke ukulwa. Ithebula elingezansi libala izinombolo ezibalulekile:
aspect | Imininingwane / Izilinganiso Zezinombolo |
|---|---|
Imikhawulo yekhasi le-IPC | I-0.1% yamabhodi e-Class 3; 0.05% ku-Class 4; 0.2% ku-Class 1 |
Ukushuba Okubalulekile | U-1.6 mm usiza amaphaneli amakhulu ukuthi ahlale eqinile uma engaphezulu kuka-400 mm |
Ukusabalalisa Kwethusi | I-Copper elinganiselayo yehlisa ingozi ye-warping ngo-15-20% |
Ukukhetha Izinto | I-High-Tg FR-4 (>170°C) noma i-polyimide (kufika ku-260°C) inciphisa ukunwetshwa cishe ngo-20% |
Ithiphu: Ukusebenza nabaqambi kusenesikhathi nokwenza amabhodi okuhlola asheshayo kungathola kufika ku-80% wezinkinga zokucaba ngaphambi kokwenza amabhodi amaningi.
Ukuxhumana Komkhiqizi-Ikhasimende
Ukuxhumana okuhle phakathi kwabenzi namakhasimende kuyasiza ukuhambisana ne-pcb. Zombili izinhlangothi kufanele zivumelane ngemithetho ye-flatness ngaphambi kokwenza amabhodi. Ukwabelana ngamapulani okunqwabelanisa, ukukhetha kwezinto ezibonakalayo, nezinyathelo zokucwasa kumisa izimanga. Abenzi bangabonisa ukuhlolwa kwekhompyutha ukuchaza ukuthi i-pcb izosebenza kanjani ngesikhathi somhlangano. Amakhasimende kufanele atshele abakhi nganoma yiziphi izinkinga ezitholakala ekuhloleni. Lokhu kusebenzisana kusiza ukuthuthukisa kokubili ukuklama nokwenza izinyathelo.
Imihlangano evamile igcina wonke umuntu enolwazi.
Ukwabelana ngemiphumela yokuhlolwa namasampuli kusiza ukulungisa izinto ngokushesha.
Ukukhuluma ngezinkinga ekwenzeni kuholela ekulungiseni okusheshayo.
Ukubhekana Nezinkinga
Uma izinkinga ze-flatness zivela, amaqembu alandela izinyathelo zokuzilungisa. Okokuqala, bahlola ukuthi ithusi liyalinganisela yini nokuthi isitaki silingana. Okulandelayo, babona ukuthi kusetshenziswe izinto ezifanele nokuqina. Uma i-lamination noma i-soldering ibangele inkinga, ishintsha izilungiselelo zenqubo. Ngezinye izikhathi, basebenzisa izibambi ezikhethekile lapho behlanganisa ukuze bagcine amabhodi angagobi. Izibonelo zezifundo zibonisa ukuthi ukuzama imiklamo emisha noma ukushintsha indlela izingxenye ezinamathiselwe ngayo kungalungisa izinkinga ezinzima. Isibonelo, iphrojekthi yezinzwa yaseYurophu ithole ukucaba okungcono ngokuhlola imiklamo emithathu emisha. Lokhu kwabasiza ekwenzeni amabhodi amaningi. Emishinini yezokwelapha, ukwenza amabhodi amaningi okuhlola kanye nokuthola usizo lwedizayini kuholele emiphumeleni engcono namabhodi aqinile.
Amaqembu athola izinkinga kusenesikhathi futhi athuthukise inqubo yawo anezinkinga ezimbalwa zokucaba kanye nokusebenza okungcono kwe-pcb.
Ukwazi amazinga e-PCB nokuthi yini ethinta ikhwalithi kusiza onjiniyela benze imikhiqizo emihle. Idizayini enhle, ukukhetha izinto ezifanele, kanye nezinyathelo ezicophelelayo kumisa amabhodi ukuthi angagobi. Lokhu kusiza futhi ukubeka izingxenye ebhodini kangcono. Ithebula elingezansi libonisa izindlela ezimbili zokusika amabhodi ngokwehlukana. Isho ukuthi indlela ngayinye ishintsha kanjani unqenqema nengcindezi:
aspect | Ukwakhiwa Kwezimbobo Zesitembu | I-V-Scoring Depaneling |
|---|---|---|
Icubungula Izindleko | Kushibhile futhi kulula ukukwenza | Kuyabiza futhi kudinga umsebenzi owengeziwe |
Ukucacisa Ikhwalithi | Imiphetho ilukhuni futhi idinga ukusikwa | Amaphethelo abushelelezi futhi abukeka emuhle |
I-Depaneling Stress | Ingcindezi ayiningi, ilungele izingxenye ezintekenteke | Ukucindezeleka okuningi, ngakho izingxenye zidinga ukuvikelwa |
Design Ukuvumelana nezimo | Isebenza kumajamo amaningi nemiklamo | Isebenza kuphela kumajamo alula, avamile |
Izimo Ezifanelekile | Ilungele imisebenzi emincane namabhodi okuhlola | Kungcono kakhulu ukwenza amabhodi amaningi okufanele abe flat |
Ukuze uthole usizo olwengeziwe, hlola i-IPC-6012 kanye nemithetho ye-IPC-2221. Ukuhlola amabhodi njalo nokusebenza ndawonye kusiza wonke umuntu ukuthi athole imiphumela engcono.
Imibuzo Evame Ukubuzwa
Yini eyenza i-PCB ilahlekelwe ukucaba?
Izinto eziningi zingenza i-PCB ingabi flat. Uma ithusi lingasakazwa ngokulinganayo, ibhodi lingagoba. Ukukhetha izinto ezingalungile nakho kudala izinkinga. Ukushisa ngesikhathi sokwenza ibhodi kungabangela umnsalo noma ukusonta. Abaqambi nabakhi kufanele babheke lezi zinto ukuze bagcine ibhodi liyisicaba.
Onjiniyela balinganisa kanjani i-PCB flatness?
Onjiniyela basebenzisa amathuluzi akhethekile ukuhlola flatness. Amanye amathuluzi i-shadow moiré, i-fringe projection, ne-confocal measurement. Balandela imithetho evela ku-IPC-TM-650. Ibhodi lihamba phezu kwetafula eliyisicaba. Bese behlola izindawo eziphakeme neziphansi kakhulu. Lokhu kusiza ukuqinisekisa ukuthi ibhodi lilungele ukusetshenziswa.
Kwenzekani uma i-PCB yehluleka izindinganiso zokulala?
Uma i-PCB ingeyisicaba ngokwanele, ingabangela inkinga. Izingxenye zingase zingalingani kahle ebhodini. Amalunga e-solder angaba buthakathaka futhi aphuke. Lokhu kungenza ibhodi liyeke ukusebenza noma lingahlali isikhathi eside. Abenzi kufanele balungise inkinga ngaphambi kokusebenzisa ibhodi.
Ingabe izinguquko zedizayini zingathuthukisa ukugcwala kwe-PCB?
Yebo, izinguquko zedizayini zingasiza ukugcina amabhodi aphansi. Onjiniyela balinganisa izendlalelo zethusi futhi bakhethe izinto ezinhle. Bahlela ukuthi isitaki silingane. Abasebenzisi ama-cutouts amakhulu futhi babeke izingxenye ezindaweni ezihlakaniphile. Lezi zinyathelo zisiza ukumisa umnsalo nokusonteka lapho wenza ibhodi.
