Daim npog qhov ncauj, tseem hu ua daim npog qhov ncauj qhov ncauj, yog txheej tuab ntawm cov polymer siv rau PCB pawg thawj coj saib los tiv thaiv cov pob qij txha txuas los ntawm Kev Txhim Kho. Lub npog ntsej muag vuam tseem tiv thaiv kev oxidation thiab siv rau cov kab tooj liab ntawm PCB pawg thawj coj.

What is PCB solder resistance type? The PCB welding mask acts as a protective coating on the copper trace line to prevent rust and prevent solder from forming Bridges that lead to short circuits. Muaj 4 yam tseem ceeb ntawm PCB vuam qhov ncauj qhov ntswg – cov tshuaj epoxy, cov duab ua kua, cov duab zaj duab xis tuaj yeem qhuav qhuav, thiab lub qhov ncauj sab saum toj thiab hauv qab.

Plaub hom vuam qhov ncauj qhov ntswg

Vuam lub ntsej muag sib txawv hauv kev tsim khoom thiab khoom siv. Yuav siv lub npog ntsej muag li cas thiab siv qhov twg yog nyob ntawm daim ntawv thov.

Sab saum toj thiab hauv qab npog

Sab saum toj thiab hauv qab vuam daim npog ntsej muag Cov kws tsim hluav taws xob feem ntau siv nws los txheeb xyuas qhov qhib hauv cov kab ntsuab ntsuab thaiv txheej. Cov txheej yog ua ntej ntxiv los ntawm epoxy resin lossis zaj duab xis thev naus laus zis. Cov pins tivthaiv tom qab ntawd txuas rau lub rooj tsavxwm siv qhov qhib sau npe nrog daim npog ntsej muag.

The conductive trace pattern on the top of the circuit board is called the top trace. Zoo ib yam li daim npog sab saum toj, daim npog sab hauv qab yog siv rau sab nraub qaum ntawm lub rooj tsav xwm txheej.

Daim npog ntsej muag Epoxy kua

Epoxy resins are the cheapest alternative to welding masks. Epoxy is a polymer that is screen printed on a PCB. Vijtsam luam ntawv yog txheej txheem luam ntawv uas siv cov ntaub npuag los txhawb nqa tus qauv thaiv tus lej. The grid allows identification of open areas for ink transfer. In the final step of the process, heat curing is used.

Cov kua ua kua pom qhov muag qhov ncauj qhov ncauj

Cov qhov ncauj qhov muag photoconductive ua kua, tseem hu ua LPI, yog qhov sib xyaw ntawm ob hom kua sib txawv. Liquid components are mixed prior to application to ensure a longer shelf life. It is also one of the more economical of the four different PCB solder resistance types.

LPI tuaj yeem siv rau kev tshuaj ntsuam luam ntawv, tshuaj pleev xim rau xim lossis tshuaj tsuag. The mask is a mixture of different solvents and polymers. Raws li qhov tshwm sim, cov txheej tuab tuaj yeem muab rho tawm uas ua rau thaj tsam ntawm thaj chaw phiaj xwm. Lub npog ntsej muag no yog npaj rau kev siv lub qhov ncauj qhov ntswg, tab sis PCB tsis xav tau ib qho ntawm cov txheej txheej txheej kawg uas niaj hnub no muaj.

Hauv kev sib piv rau cov laus epoxy inks, LPI nkag siab rau lub teeb ci ultraviolet. Lub vaj huam sib luag yuav tsum tau npog nrog daim npog ntsej muag. Tom qab luv “kho lub voj voog”, pawg thawj coj tau nthuav tawm lub teeb ci ultraviolet siv photolithography lossis ultraviolet laser.

Before applying the mask, the panel should be cleaned and free of oxidization. Qhov no yog ua tiav nrog kev pab tshwj xeeb tshuaj daws teeb meem. Qhov no tseem tuaj yeem ua tiav siv cov tshuaj alumina lossis los ntawm txhuam cov vaj huam sib luag nrog pob zeb pumice raug tshem tawm.

One of the most common ways to expose panel surfaces to UV is by using contact printers and film tools. The top and bottom sheets of the film are printed with an emulsion to block the area to be welded. Use the tools on the printer to fix the production panel and film in place. The panels were then simultaneously exposed to an ULTRAVIOLET light source.

Lwm cov txheej txheem siv lasers los tsim cov duab ncaj qha. But in this technique, no film or tools are needed because the laser is controlled using a reference mark on the panel’s copper template.

LPI qhov ncauj qhov ntswg tuaj yeem pom muaj ntau yam xim, suav nrog ntsuab (matte lossis semi-gloss), dawb, xiav, liab, daj, dub, thiab ntau dua. Kev lag luam LED thiab kev siv laser hauv kev lag luam hluav taws xob tau txhawb nqa cov tuam ntxhab thiab cov tsim qauv tsim kom muaj zog cov ntaub ntawv dawb thiab dub.

Zaj duab xis qhuav daim duab thaij duab daim npog qhov ncauj

A dry film photoimagable welding mask is used, and vacuum lamination is used. Cov zaj duab xis qhuav tau nthuav tawm thiab tsim tawm. After the film is developed, openings are positioned to produce patterns. Tom qab qhov no, lub hauv paus tau txuas rau lub ncoo brazing. Cov tooj liab yog tom qab laminated mus rau lub rooj tsav xwm Circuit Court siv cov txheej txheem hluav taws xob.

Cov tooj liab yog txheej hauv lub qhov thiab hauv qhov chaw taug. Thaum kawg Tin tau siv los pab tiv thaiv cov tooj liab. In the final step, the membrane is removed and the etching mark is exposed. Txoj hauv kev kuj tseem siv cua sov ua kom sov.

Dry film welding masks are commonly used for high-density patch boards. Raws li qhov tshwm sim, nws tsis nchuav rau hauv qhov hla. These are some of the positives of using a dry film welding mask.

Kev txiav txim siab siv lub npog ntsej muag dab tsi los siv yog nyob ntawm ntau yam sib txawv – suav nrog lub cev me me ntawm PCB, daim ntawv thov zaum kawg uas yuav siv, lub qhov, cov khoom siv uas yuav tsum tau siv, tus neeg ua haujlwm, txheej txheej saum npoo, thiab lwm yam.

Feem ntau cov qauv PCB niaj hnub tuaj yeem tau txais cov duab thaij duab tiv thaiv cov yeeb yaj kiab. Therefore, it is either LPI or dry film resistance film. The surface layout of the board will help you determine your final choice. If the surface topography is not uniform, the LPI mask is preferred. If a dry film is used on uneven terrain, gas may be trapped in the space formed between the film and the surface. Therefore, LPI is more suitable here.

Txawm li cas los xij, muaj qhov tsis zoo rau siv LPI. Its comprehensiveness is not uniform. You can also get different finishes on the mask layer, each with its own application. For example, in cases where solder reflow is used, the matte finish will reduce solder balls.

Build solder masks into your design

Kev tsim cov yeeb yaj kiab tiv thaiv zaj duab xis rau hauv koj tus qauv tsim yog qhov tseem ceeb kom ntseeg tau tias daim npog ntsej muag yog nyob rau qib zoo. When designing a circuit board, the welding mask should have its own layer in the Gerber file. In general, it is recommended to use a 2mm border around the function in case the mask is not fully centered. Koj tseem yuav tsum tso qhov tsawg kawg ntawm 8mm nruab nrab ntawm cov ntaub qhwv kom ntseeg tau tias Bridges tsis tsim.

Thickness of welding mask

Thickness Welding mask will depend on the thickness of the copper trace on the board. Feem ntau, ib daim npog 0.5 hli yog qhov zoo dua los npog qhov kab. If you are using liquid masks, you must have different thicknesses for different features. Cov cheeb tsam laminate npliag yuav muaj qhov tuab ntawm 0.8-1.2mm, thaum thaj chaw uas muaj cov yam ntxwv nyuaj xws li hauv caug yuav muaj qhov txuas ntxiv (li 0.3mm).

xaus

Hauv kev xaus, kev tsim daim npog ntsej muag muaj kev cuam tshuam loj rau daim ntawv thov kev ua haujlwm. Nws ua lub luag haujlwm tseem ceeb hauv kev tiv thaiv xeb thiab vuam txuas, uas tuaj yeem ua rau luv Circuit Court. Yog li, koj qhov kev txiav txim siab yuav tsum coj mus rau hauv tus account qhov sib txawv tau hais hauv kab lus no. Vam tias tsab xov xwm no tuaj yeem pab koj nkag siab TYPE ntawm PCB tsis kam ua zaj duab xis. Yog tias koj muaj lus nug, lossis tsuas yog xav tau hu rau peb, peb ib txwm zoo siab los pab koj.