IC afifi faʻamoemoe i ai PCB mo le faʻasalalauina o le vevela. In general, PCB is the main cooling method for high power semiconductor devices. A good PCB heat dissipation design has a great impact, it can make the system run well, but also can bury the hidden danger of thermal accidents. O le faʻaeteete faʻatonutonuina ole faʻamaumauga ole PCB, faʻatulagaina ole laupapa, ma mea e faʻapipiʻi ai masini e mafai ona fesoasoani e faʻaleleia atili ai le faʻataʻapeina ole vevela mo mea feololo – ma maualuga le paoa.

Semiconductor gaosi e faigata ona puleaina polokalama e faʻaaogaina a latou masini. Peitai, o se faiga ma le IC faʻapipiʻi e taua tele i le aotelega masini faʻatinoina. Mo aganuu IC masini, o le faiga tisaini masani ona galulue vavalalata ma le gaosi oloa ia mautinoa o le polokalama faʻamalieina le tele o vevela faʻasologa manaʻoga o maualuga-paoa masini. O lenei vave galulue faʻatasi mautinoa le faʻafetauiina o le IC eletise ma faʻatinoga tulaga, a o mautinoa le faʻagaioiga lelei i totonu o le tagata faʻatauina faiga. Many large semiconductor companies sell devices as standard components, and there is no contact between the manufacturer and the end application. I lenei tulaga, e naʻo nai taʻiala lautele e mafai ona matou faʻaogaina e fesoasoani ai i se faʻamalieina lelei o le faʻavaivaia o le vevela mo le IC ma le faiga.

Faʻafefea ona mamanuina dissipation vevela mo PCB

Masani semiconductor afifi ituaiga o fanauina pad po o le PowerPAD TM afifi. In these packages, the chip is mounted on a metal plate called a chip pad. Lenei ituaiga o malamala pad lagolagoina le malamala i le faʻagasologa o malamala gaosi, ma o se lelei lelei auala vevela foi mo masini faʻaseseina vevela. When the packaged bare pad is welded to the PCB, heat is quickly exited from the package and into the PCB. The heat is then dissipated through the PCB layers into the surrounding air. O lapoʻa pad afifi masani fesiitai e uiga i le 80% o le vevela i totonu o le PCB ala i le pito i lalo o le afifi. O le totoe 20% o le vevela o loʻo faʻasalalau e ala i uaea masini ma itu eseese o le afifi. Lalo i le 1% o le vevela e sosola ese mai le pito i luga o le afifi. I le tulaga o nei lavalava-pad afifi, lelei PCB vevela faʻasalalauina vevela fuafuaga e taua e mautinoa ai nisi faʻatinoina masini.

O le vaega muamua o le PCB design e faʻaleleia atili ai le faʻamaluluina o le faʻataʻitaʻiina o masini PCB. Soʻo se taimi e mafai ai, e tatau ona tuʻu eseʻese vaega maualuga-paoa i luga ole PCB mai le tasi ma le isi. O lenei vavalalata vavalalata i le va o le maualuga-malosi elemeni faʻateleina le PCB eria faataamilo i vaega maualuga-paoa, lea e fesoasoani faʻamalieina sili vevela suiga. Care should be taken to separate temperature sensitive components from high power components on the PCB. Soʻo se mea e mafai ai, e tatau ona tuʻu eseʻesega paoa maualuga mai tulimanu ole PCB. O se sili atu vailauga tulaga PCB faʻateleina le laupapa eria faataamilo i le maualuga-paoa vaega, lea fesoasoani i le faʻateʻaina vevela. Lua tutusa semiconductor masini o loʻo faʻaalia: vaega A ma le B. Vaega A, o loʻo tu i le tulimanu o le PCB, ei ai le vaeluaina vevela vevela 5% maualuga atu nai lo le vaega B, lea o loʻo faʻatulagaina sili tutotonu. O le faʻaseseina o le vevela i le tulimanu o le elemeni A e faʻatapulaʻaina e le vaega laʻititi laʻau o loʻo siʻomia ai le vaega na faʻaaogaina mo le faʻaseseina o le vevela.

O le vaega lona lua o le fausaga o PCB, lea e i ai le sili ona taua aʻafiaga i luga o le vevela faatinoga o PCB mamanu. I le avea ai o se tulafono lautele, o le tele o le ‘apamemea o loʻo i ai le PCB, o le maualuga atu ai lea o le vevela faʻatinoina o vaega o vaega. O le tulaga lelei faʻamamaina vevela mo semiconductor masini o le malamala o loʻo faʻatiʻetiʻe luga o le tele poloka o suavai-faʻamamaina kopa. E le aoga lea mo le tele o apalai, o lea na tatau ai ona matou faia isi suiga i le PCB e faʻaleleia atili ai le faʻaseseina o le vevela. For most applications today, the total volume of the system is shrinking, adversely affecting heat dissipation performance. Larger PCBS have more surface area that can be used for heat transfer, but also have more flexibility to leave enough space between high-power components.

Soʻo se taimi e mafai ai, faʻatele le numera ma le mafiafia o PCB apamemea faaputuga. O le mamafa o grounding ‘apamemea e masani ona lapoʻa, o se sili lelei auala vevela mo le atoa faʻaseseina vevela PCB. The arrangement of the wiring of the layers also increases the total specific gravity of copper used for heat conduction. Ae ui i lea, o lenei uaea e masani lava ona faʻaaogaina eletise, faʻatapulaʻaina lona faʻaaogaina o se ono goto vevela. O le masini grounding e tatau ona faʻaaogaina i le eletise pe a mafai i le tele o grounding layer pe a mafai e fesoasoani ai i le faʻateleina o le vevela conduction. O le faʻamamaina o le pu i le PCB i lalo ifo o le semiconductor masini e fesoasoani i le vevela e faʻaulu i totonu o le PCB ma faʻasolo i tua o le laupapa.

O le pito i luga ma lalo o le PCB o “nofoaga sili” mo le faʻaleleia atili o le faʻamaluluina o galuega. Faʻaaogaina lautele lautele uaea ma taamilosaga ese mai maualuga-mana masini mafai ona maua ai se vevela ala mo vevela faʻasalalauina. Laupapa conduction vevela faʻapitoa o se sili lelei metotia mo PCB vevela faʻasalalauina. O le vevela conductive ipu o lo oi luga o le pito i luga po o tua o le PCB ma e fesoʻotaʻi thermally i le masini ala atu i soʻo se fesoʻotaʻiga ‘apamemea fesoʻotaʻi poʻo se vevela ala-lua. I le tulaga o le afifiina o laina (naʻo taʻitaʻiga i itu uma o le afifi), o le vevela conduction ipu mafai ona tu i luga o le pito i luga o le PCB, foliga pei o se “taifau ponaivi” (o le ogatotonu e vaapiapi pei o le afifi, le ‘apamemea alu ese mai le afifi ei ai se tele vaega, laʻititi i le ogatotonu ma tele i pito uma). I le tulaga o le fa itu itu afifi (ma taʻi i itu uma e fa), o le vevela conduction ipu tatau ona tu i tua o le PCB poʻo totonu o le PCB.

Faateleina le tele o le vevela conduction ipu o se sili lelei auala e faʻaleleia ai le vevela faʻatinoina o PowerPAD afifi. Different size of heat conduction plate has great influence on thermal performance. O le laupepa faʻamaumauga oloa e masani lava ona lisiina nei itu. Ae o le faʻatusatusaina o le aʻafiaga o le faʻaopopoina o le kopa i le PCBS masani e faigata. With online calculators, users can select a device and change the size of the copper pad to estimate its effect on the thermal performance of a non-JEDEC PCB. O nei mea faigaluega fuafuaina e faʻamamafa ai le tele e faʻatosina ai e le PCB design le faʻaleagaina o le vevela. For four-side packages, where the area of the top pad is just less than the bare pad area of the device, embedding or back layer is the first method to achieve better cooling. Mo itulua i-laina afifi, e mafai ona tatou faʻaaogaina le “dog dog” pad style e faʻateʻa ai le vevela.

I le iuga, faiga ma tele PCBS mafai foi ona faʻaaogaina mo le maluluina. The screws used to mount the PCB can also provide effective thermal access to the base of the system when connected to the thermal plate and ground layer. Mafaufauga i le vevela conductivity ma tau, o le numera o faovilivili e tatau ona faʻateleina i le tulaga o le faʻaitiitia o tupe maua. O le uamea PCB faʻamalosi e sili atu le malulu o le eria pe a maeʻa ona fesoʻotaʻi i le vevela ipu. Mo nisi tusi talosaga o loʻo i ai le atigi PCB fale, o le TYPE B solder patch mea o loʻo i ai se maualuga vevela faʻataʻitaʻiga nai lo le ea faʻamafanafana atigi. O fofo malulu, e pei o ili ma paʻu, e masani foʻi ona faʻaaoga mo le faʻamaluluina o le tino, ae e masani ona manaʻomia ni avanoa se tele pe manaʻomia ni fesuiaʻiga e faʻalelei ai le faʻaliliuga.

Ina ia mamanuina se faiga ma maualuga vevela faʻagaioiga, e le lava le filifilia o se lelei IC masini ma tapunia vaifofo. IC faʻamaluluina faʻatulagaina faʻatulagaina faalagolago i luga o le PCB ma le gafatia o le faʻamaluluina polokalama e faʻatagaina ai IC masini e malulu vave. O le auala pasi malu o loʻo taʻua i luga e mafai ona matua faʻaleleia atili ai le vevela faʻasoloina gaioiga o le tino.