Umhlahlandlela Wokuklama we-Aluminium LED PCB kanye ne-DFM

Izinga lokushisa le-LED junction liyi-variable eyodwa enquma izinga lokwehla kwe-lumen, ukushintsha kombala, kanye nesikhathi sokwehluleka. Konke okuseklanyweni le-aluminium LED PCB kungaba negalelo noma kunciphisa izinga lokushisa le-junction. Umklami oqonda uchungechunge lokushisa oluvela ku-junction kuya ku-ambient angenza izinqumo zokwakheka ezibuyisa umkhawulo ongu-10–20°C kusuka ku-heatsink ethile. Umklami ophatha i-PCB njenge-substrate yokufaka ngomshini futhi ashiye ukulungiswa kokushisa kumthengisi we-heatsink ubuyisela lowo mkhawulo ngokungadingekile. Lo mhlahlandlela uhlanganisa izinqumo zokuklama ezibalulekile.

Uchungechunge Lokushisa: Lapho Ukushisa Kuya Khona Nalapho Kuma Khona

Ukuzulazula kwesihloko

1. Uchungechunge Lokushisa: Lapho Ukushisa Kuya Khona Nalapho Kuma Khona
2. Ukusebenzisa Ukulingisa Okushisayo Ngaphambi Kokuzibophezela Ekuhlelweni
3. I-LED Pad Geometry: Ukunemba Kwezinyawo kanye Nokuthembeka Kwamalunga E-Solder
4. Ububanzi Be-Copper Trace Yezintambo Ze-LED Ezinamandla Aphezulu
5. Izindawo Zokugcina kanye Nebanga Lokuqhekeka Kwabashayeli Be-LED Abahlanganisiwe
6. Imithetho ye-DFM Eqondene Nokwakheka kwe-Aluminium LED PCB
7. Uhlu Lokuhlola Lokudluliswa Komklamo Lokwenziwa Kwe-PCB Ye-Aluminium LED
8. Imibuzo Evame Ukubuzwa

Ukushisa kugeleza kusuka ekuhlanganeni kwe-LED → iphakheji ye-LED → ijoyinti le-solder → i-copper pad → ungqimba lwe-dielectric → isisekelo se-aluminium → i-heatsink → i-ambient. I-interface ngayinye inenani lokumelana nokushisa, kanti i-PCB inikela ngezinto ezintathu: ukumelana kwejoyinti le-solder, i-interface yethusi-kuya-dielectric, kanye nengqimba ye-dielectric uqobo.

Ukumelana ne-dielectric yigama eliphambili le-PCB lokushisa:

• Ku-1.0 W/m·K, 100 µm i-dielectric: θ_dielectric ≈ 1.0°C/W nge-cm² yendawo yephedi
• Ku-2.0 W/m·K, 100 µm: θ_dielectric ≈ 0.5°C/W nge-cm² ngayinye
• Ku-3.0 W/m·K, 100 µm: θ_dielectric ≈ 0.33°C/W nge-cm² ngayinye

Ku-LED engu-3W ku-pad engu-3 × 3 mm, umehluko phakathi kwe-dielectric engu-1.0 no-3.0 W/m·K cishe u-5°C wokushisa kwe-junction ku-die. Kala lokho ku-fixture engu-150W enama-LED angu-50 futhi umthelela wezinga lesistimu ubalulekile.

Isisekelo se-aluminium sengeza ukumelana nokushisa okuncane uma sinobukhulu obanele (≥1.0 mm) futhi isixhumi esibonakalayo se-heatsink sisebenzisa i-TIM efanele (izinto ezibonakalayo ze-thermal interface). Isixhumi esibonakalayo se-base-to-heatsink sivame ukuba ukumelana nokushisa okukhulu kakhulu ekuhlanganisweni — kodwa singaphandle kokulawulwa okuqondile komklami we-PCB.

Ukusebenzisa Ukulingisa Okushisayo Ngaphambi Kokuzibophezela Ekuhlelweni

Ukulingisa ukushisa ngaphambi kokuhlelwa kwe-PCB kuvimbela amaphutha amabili abizayo: ukwakha ibhodi elingakwazi ukupholisa ngokwanele ngamandla alinganisiwe, kanye nokucacisa ngokweqile i-dielectric ngezindleko ezingadingekile.

Okokufaka kwe-FEA kokulingisa kwe-aluminium LED PCB:

• Ukumelana nokushisa kwephakheji ye-LED (θ_j-s, kusuka kushidi ledatha)
• Amandla e-LED aqhubekela phambili kumanje okusebenza
• Ubukhulu bephedi kanye ne-thermal slug
• Ibanga le-dielectric kanye nobukhulu (lena yipharamitha oyixazululelayo)
• Ubukhulu besisekelo se-aluminium kanye ne-alloy
• Ukumelana ne-Heatsink kanye ne-interface yokufaka inani le-TIM
• Izinga lokushisa elizungezile (okubi kakhulu: ngokuvamile lingama-50–60°C ezibanini ezivalekile)

Lokho okushiwo umphumela wokulingisa:

• Izinga lokushisa eliphezulu le-LED junction — qhathanisa nesilinganiso se-T_j (ngokuvamile 125–150°C kumaphakheji e-LED esimanje)
• Izindawo ezishisayo ezivela ekuhlanganisweni kwe-LED — uma ama-LED ebekwe eduze kakhulu, ukumelana nokushisa okuvela emithonjeni yokushisa ye-LED eseduze kunezela ekushiseni kwe-junction
• I-Tc ye-dielectric edingekayo ukuze ihlale ngaphakathi kwesabelomali sokushisa kwe-junction

I-Highleap Electronics inikeza ukwesekwa kokulingisa ukushisa kwe-MCPCB kumakhasimende adinga ukuqinisekisa imininingwane yawo ye-stack ngaphambi kokuzibophezela ekukhiqizeni. Lokhu kuwusizo ikakhulukazi lapho ukukhetha phakathi kwe-dielectric engu-2.0 no-3.0 W/m·K kuthinta kakhulu izindleko zezinto.

I-LED Pad Geometry: Ukunemba Kwezinyawo kanye Nokuthembeka Kwamalunga E-Solder

I-geometry yama-pad kuma-PCB e-aluminium LED inemiphumela eqinile kune-FR-4 ejwayelekile ngoba isisindo sokushisa sesisekelo se-aluminium siphezulu futhi ukulawula izinga lokushisa kabusha kunzima. Amaphutha avamile okuklama ama-pad:

Ama-thermal pad amakhulu kakhulu : I-thermal slug pad enkulu kune-slug footprint yephakheji ye-LED idala indawo yokugcina i-solder ngesikhathi sokugeleza kabusha engasusa i-solder kuma-signal pad, okubangela ukwakheka okunganele kwamalunga kuma-signal/anode/cathode pads. Usayizi we-thermal pad ngu-0–0.1 mm ohlangothini ngalunye mkhulu kune-package thermal slug, hhayi u-0.3–0.5 mm njengoba ngezinye izikhathi kuchazwe ku-FR-4.

Isilinganiso sokuvuleka kwemaski ye-solder : Kuma-thermal pad amakhulu (>3 × 3 mm), sebenzisa ukuvuleka kwemaski ye-solder ehlukaniswe ngezigaba — ukuvuleka okuncane okuningi kune-pad eyodwa evezwe ngokuphelele — ukulawula ivolumu yokunamathisela nokuvimbela ukuphuma. Qonda ukuchayeka kwendawo yethusi okungu-50–70% kuma-pad ≥ 9 mm².

I-pad coplanarity : Amabhodi e-aluminium anobukhulu be-dielectric obuhlukahlukene obugobile kancane ngesikhathi sokugeleza kabusha. I-pad coplanarity engu-≤0.05 mm ingatholakala ngobukhulu be-dielectric obulawulwayo. Uma ukuphrinta kwakho kokunamathisela kuncike ku-tight coplanarity, xoxa ngalokhu nefektri njengencazelo elawulwayo. Hlola ukuthi ukwakheka kwemaski ye-solder kuma-PCB kuthinta kanjani isivuno sokuhlanganiswa kuma-substrates ensimbi.

Ububanzi Be-Copper Trace Yezintambo Ze-LED Ezinamandla Aphezulu

Izinga le-IPC-2152 (elaliyi-IPC-2221) linikeza inkomba yobubanzi bokulandelela uma kuqhathaniswa nomthamo wamanje. Kuma-PCB e-aluminium LED, sebenzisa amatafula okulandelela wezendlalelo zangaphakathi kunezendlalelo zangaphandle — ngoba umkhondo ungaphezulu kodwa isisekelo se-aluminium simunca ukushisa okuvela ngaphansi, okuphindaphinda kancane ukuziphatha kokushisa kwezendlalelo zangaphakathi.

Iziqondiso zobubanzi bomkhondo ezisebenzayo zama-PCB e-LED ethusi angu-1 oz ku-aluminium, ukuphakama okungu-10°C:

Kuma-currents angaphezu kuka-5 A, shintshela ku-2 oz noma 3 oz yethusi. Ububanzi bokulandelela obudingekayo ku-1 oz ku-10 A (5 mm) budla indawo yokwakheka esetshenziswa kangcono kuma-LED engeziwe kumiklamo yobuningi obukhulu. Hlola izimiso zokuklama i-PCB yethusi esindayo lapho isisindo sethusi sidlula u-2 oz.

Izindawo Zokugcina kanye Nebanga Lokuqhekeka Kwabashayeli Be-LED Abahlanganisiwe

Imiklamo eminingi ye-aluminium LED PCB ihlanganisa isekethe yomshayeli we-LED ebhodini elifanayo ne-LED array. Lokhu kudala isifunda se-high-voltage (uhlangothi lokufaka umshayeli: 100–350V AC noma DC) eduze kwentambo ye-LED ene-low-voltage. Imithetho yokuklama:

Ibanga lokucwila : I-IEC 60950-1 kanye ne-IEC 62368-1 zichaza izidingo zokucwila kanye nokususwa phakathi kwama-conductor ane-voltage ephezulu kanye nalawo ane-voltage ephansi. Ukuze kuqiniswe ukufudumala ku-voltage yokusebenza engu-250V AC, ibanga elincane lokucwila ku-PCB lingu-6.4 mm (Ukungcola Idigri 2, Iqembu Lezinto IIIa). Kuma-PCB e-aluminium LED lapho isisekelo se-aluminium sikhona khona, ibanga ukusuka kunoma yimuphi umqhubi ophilayo kuya onqenqemeni lwebhodi eliseduze noma emgodini wokufaka nalo lidinga ukuhlaziywa kokucwila.

Ukuvimbela imigodi yokufaka ene-voltage ephezulu : Imigodi yokufaka ene-aluminium ixhuma isisekelo ne-chassis ye-fixture. Noma yimuphi umkhondo we-voltage ephezulu kumele ugcine ibanga lokuhamba/lokuphuma kulezi zimbobo, okubalwa ububanzi be-fastener eqhubayo.

Ama-pads okushisa e-Driver IC : Amanye ama-IC okushayela e-LED aveze ama-pads okushisa ngamandla aphezulu e-voltage (hhayi emhlabathini). Qinisekisa i-voltage yama-pad ngaphambi kokuthola ukuvuleka kwemaski ye-solder kanye nokuthululwa kwethusi eduze kwalezi zingxenye.

Imithetho ye-DFM Eqondene Nokwakheka kwe-Aluminium LED PCB

Umklamo Wokwenziwa Kwezinto Ezingaphansi Kwe-aluminium Uhlukile Ku-FR-4 Ezindaweni Eziningana:

Azikho izi-via kuma-thermal pad : Ngokungafani ne-FR-4 lapho kusetshenziswa khona i-via-in-pad ene-copper fill ngezinye izikhathi, ama-aluminium LED PCB awasekeli izi-via ezifihliwe noma ezingaboni. Konke ukuqondisa kumele kwenziwe ngesendlalelo esisodwa se-copper. Ukuthululwa kwe-copper kanye ne-wide traces kuthatha indawo yokusabalala kokushisa okusekelwe ku-via.

Indandatho encane ye-annular yokubhoboza i-aluminium : Ngenxa yokukhuhla kwe-aluminium kwethuluzi lokubhoboza, ukuzulazula kwe-drill kuphakeme kancane kune-FR-4. Indandatho encane ye-annular yemigodi efakwe ama-plated kuma-PCB e-aluminium LED kufanele ibe ngu-0.25 mm, hhayi u-0.15 mm njengoba kungamukeleka ku-FR-4.

Ukugcinwa kwengxenye kusuka emigqeni ye-V-score : Ukugcinwa okujwayelekile kusuka ku-V-score kungu-0.5 mm kwezingxenye eziku-FR-4. Ku-aluminium, ukuhlukahluka kokujula kwe-blade ye-V-score kungaba ngu-±0.1 mm, futhi amaphuzu e-aluminium adala ukuphazamiseka okuncane kobuso. Khulisa ukugcinwa kwengxenye kusuka emigqeni ye-V-score kuya ku-0.75 mm kuma-PCB e-aluminium LED.

Ukugoba komphetho akutholakali : Ama-PCB e-aluminium LED awasekeli ukugoba komphetho. Noma yikuphi ukuxhumeka kukagesi onqenqemeni lwebhodi kumele kwenziwe ngama-pad adonswe emuva onqenqemeni ngo-≥0.5 mm.

Ukuze uthole isibuyekezo esiphelele se-DFM ngaphambi kokuthumela umklamo wakho wokukhiqiza, sebenzisa uhlu lokuhlola lwe-PCB DFM njengereferensi yangaphambi kokuthumela.

Uhlu Lokuhlola Lokudluliswa Komklamo Lokwenziwa Kwe-PCB Ye-Aluminium LED

Ngaphambi kokuthumela amafayela kumenzi:

• Amafayela e-Gerber: ungqimba lwethusi, i-solder mask top, i-silkscreen top, uhlaka lwebhodi (i-DXF noma ungqimba oluzinikele lwe-Gerber)
• Ifayela lokubhoboza: zonke izimbobo ezinobubanzi, ukubizwa okufakwe ipulasitiki/okungafakwe ipulasitiki
• Imininingwane ye-stack-up: ibanga le-aluminium, ubukhulu, ibanga le-dielectric Tc, isisindo sethusi, ubukhulu bebhodi eliphelele
• Ukucaciswa kokuphela kobuso: Ubukhulu begolide/i-nickel ye-ENIG, noma i-HASL/OSP
• Imfuneko ye-voltage ye-Hi-pot
• Ikilasi le-IPC (2 noma 3)
• Imininingwane elawulwayo: ukubekezelelana kobukhulu be-dielectric, ukubekezelelana kobukhulu bethusi
• Umbala wemaski ye-Solder kanye nesilinganiso sokuvula kuma-thermal pads amakhulu
• Ukufaka imininingwane ye-chamfer yembobo noma yesinki esiphikisayo uma kudingeka

Ithimba lobunjiniyela le-Highleap Electronics lenza isibuyekezo samahhala se-DFM kumafayela athunyelwe ngaphambi kokucaphuna, lihlonza noma yiziphi izinkinga ezingenhla ngaphambi kokuba zibe amaphutha okukhiqiza noma amabhodi enqatshiwe. Isibuyekezo siyabuyiselwa zingakapheli izinsuku ezingu-1-2 zokusebenza.

Imibuzo Evame Ukubuzwa

Yiliphi ithuluzi lokulingisa okufanele ngilisebenzise ekwakhiweni kokushisa kwe-aluminium LED PCB? I-ANSYS Icepak kanye ne-Mentor FloTHERM ngamathuluzi agcwele e-FEA anemitapo yolwazi yezinto ze-dielectric ze-MCPCB. Ukuze uthole imiphumela esheshayo ngesikhathi sokuklama kokuqala, amathuluzi okulingisa abakhiqizi be-LED (i-Lumileds SiteMap, i-OSRAM LED Expert) afaka amamodeli okushisa alula. Noma yikuphi ukulingisa kungcono kunokungabi nokulingisa - ngisho nemodeli yespredishithi yokumelana nokushisa okuhlangene kuya endaweni ibamba amaphutha amakhulu okuklama ngaphambi kokwenza iphrothotayipi.

Ngingaphatha kanjani izindiza zomhlabathi kanye namandla ku-PCB ye-aluminium LED enesendlalelo esisodwa? Amabhodi anesendlalelo esisodwa awanawo indiza yomhlabathi ngokomqondo wendabuko we-FR-4 multilayer. Amandla kanye nomhlabathi (noma ukubuya kwamanje) kumele kuqondiswe njengemikhondo ehlukene. Ukuthululwa kwethusi endaweni engasetshenziswanga kungasebenza njengezindlela zokubuya kwamanje wendawo kodwa akuxhunywanga ngogesi esisekelweni se-aluminium. Isisekelo se-aluminium kungaba umhlabathi we-chassis noma sintanta, kuye ngomklamo wezinto — hhayi umhlabathi wesekethe ngokuzenzakalelayo.

Yikuphi ukuqedwa kwephedi okufanele ngikucacisele ngama-array e-COB LED kumabhodi e-aluminium? I-ENIG iyisinqumo esifanele sokuhlanganiswa kwe-COB (chip-on-board) ye-LED PCB . Ubuso obuyisicaba, obuphindaphindwayo bubalulekile ezinqubweni zokubopha nge-die attachment kanye ne-wire bonding ezisetshenziswa ekukhiqizweni kwe-COB. Ukwehluka kobuso be-HASL akuhambisani nokubekezelelana kokuphakama kwebhondi ekuhlanganisweni kwe-COB.

Isisekelo se-aluminiyamu siyithinta kanjani iphrofayili yokugeleza kabusha kwe-SMT? Isisekelo se-aluminiyamu simunca ukushisa ngesikhathi sokukhuphuka, kudinga izinga lokukhuphuka elihamba kancane (ubuningi obungu-2°C/s) kanye nokushisa okuphezulu okungenzeka kube phezulu ukuze kufinyelelwe izinga lokushisa elifanele lephedi. Isisekelo sigcina nokushisa ngemva kokushiya izindawo eziphakeme, sandise isikhathi esingaphezu kwe-liquidus. Cela iphrofayili yokugeleza kabusha ezinikele kumlingani wakho womhlangano uma ushintsha kusuka ku-FR-4 kuya kuma-PCB e-aluminium LED.