Maskurin walda, wanda kuma aka sani da mashin toshe mai siyarwa, shine siririn polymer da ake amfani dashi Kwamitin PCB don hana gidajen abinci masu siyarwa su kafa Gado. Maskurin walda shima yana hana hadawan abu da iskar shaka kuma ya shafi alamomin tagulla akan allon PCB.

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. Akwai manyan nau’ikan masarrafan walda na PCB 4 – ruwan epoxy, hoto mai ɗaukar hoto, hoto mai bushewar hoto, da masakun sama da ƙasa.

Nau’i huɗu na abin rufe fuska

Masks ɗin waldi sun bambanta a ƙira da kayan aiki. Ta yaya kuma wane abin rufe fuska don amfani ya dogara da aikace -aikacen.

Rufin gefen sama da ƙasa

Mashin walƙiya na sama da ƙasa Masu aikin injiniya na lantarki galibi suna amfani da shi don gano buɗewa a cikin katanga mai shinge. An riga an ƙara Layer ta resin epoxy ko fasahar fim. Ana toshe sassan fil ɗin zuwa allon ta amfani da buɗaɗɗen rajista tare da abin rufe fuska.

The conductive trace pattern on the top of the circuit board is called the top trace. Mai kama da abin rufe fuska na sama, ana amfani da abin rufe fuska na ƙasa a gefen baya na allon kewaye.

Mask ɗin mai siyar da ruwa

Epoxy resins are the cheapest alternative to welding masks. Epoxy is a polymer that is screen printed on a PCB. Bugun allo tsari ne na bugawa wanda ke amfani da gidan yadi don tallafawa tsarin toshe tawada. The grid allows identification of open areas for ink transfer. In the final step of the process, heat curing is used.

Liquid Tantancewar hoto solder mask

Abubuwan rufe fuska masu ɗaukar hoto, wanda kuma aka sani da LPI, a zahiri cakuda ruwa biyu ne daban -daban. 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.

Ana iya amfani da LPI don bugun allo, zanen allo ko aikace -aikacen fesawa. The mask is a mixture of different solvents and polymers. A sakamakon haka, ana iya fitar da mayafi na bakin ciki waɗanda ke manne a saman yankin da ake nufi. Anyi nufin wannan abin rufe fuska don rufe masakun, amma PCB baya buƙatar kowane abin rufe fuska na ƙarshe da aka saba samu yau.

Ya bambanta da tsoffin inks na epoxy, LPI yana kula da hasken ultraviolet. Ana buƙatar rufe kwamitin da abin rufe fuska. Bayan ɗan gajeren “sake zagayowar warkarwa”, ana fallasa allon ga hasken ultraviolet ta amfani da photolithography ko laser ultraviolet.

Before applying the mask, the panel should be cleaned and free of oxidization. Ana yin wannan tare da taimakon magunguna na musamman. Hakanan ana iya yin wannan ta amfani da maganin alumina ko ta goge bangarori tare da dakatar da ƙura.

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.

Wata dabara tana amfani da lasers don ƙirƙirar hotuna kai tsaye. 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.

Ana iya samun mashin LPI a cikin launuka iri-iri, gami da kore (matte ko Semi-gloss), fari, shuɗi, ja, rawaya, baki, da ƙari. Masana’antar LED da aikace -aikacen laser a cikin masana’antar lantarki suna ƙarfafa masana’antun da masu zanen kaya don haɓaka kayan fari da baƙar fata masu ƙarfi.

Dry film photoimaging solder mask

A dry film photoimagable welding mask is used, and vacuum lamination is used. Daga nan sai fallasa busasshen fim ɗin ya bunƙasa. After the film is developed, openings are positioned to produce patterns. Bayan wannan, ana haɗa walƙiya zuwa farantin brazing. Daga nan sai a dora tagulla akan allon da’irar ta amfani da tsarin lantarki.

An sanya tagulla a cikin rami da cikin wurin da aka gano. Tin was eventually used to help protect copper circuits. In the final step, the membrane is removed and the etching mark is exposed. Hakanan hanyar tana amfani da maganin zafi.

Dry film welding masks are commonly used for high-density patch boards. A sakamakon haka, ba ya shiga cikin rami. These are some of the positives of using a dry film welding mask.

Yanke wane abin rufe fuska don amfani ya dogara da dalilai daban -daban – gami da girman jiki na PCB, aikace -aikacen ƙarshe da za a yi amfani da shi, ramukan, abubuwan da za a yi amfani da su, masu gudanar da aikin, shimfidar saman, da dai sauransu.

Yawancin ƙirar PCB na zamani na iya samun fina -finan tsayayyar solder mai ɗaukar hoto. 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.

Koyaya, akwai raguwa don amfani da 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

Building a solder resist film into your design is indispensable to ensure the mask application is at the optimal level. 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. Hakanan yakamata ku bar mafi ƙarancin 8mm tsakanin pads don tabbatar da cewa Bridges basu yi ba.

Thickness of welding mask

Thickness Welding mask will depend on the thickness of the copper trace on the board. Gabaɗaya, an fi son abin rufe fuska 0.5mm don rufe layin ganowa. If you are using liquid masks, you must have different thicknesses for different features. Empty laminate areas may have a thickness of 0.8-1.2mm, while areas with complex features such as knees will have thin extensions (about 0.3mm).

ƙarshe

A taƙaice, ƙirar abin rufe fuska tana da tasiri mai tasiri akan aikin aikace -aikacen. Yana taka muhimmiyar rawa wajen hana tsatsa da walda Gado, wanda zai iya haifar da gajerun da’irori. Don haka, shawarar ku na buƙatar yin la’akari da abubuwan da aka ambata a cikin wannan labarin. Da fatan wannan labarin zai iya taimaka muku mafi kyawun fahimtar TYPE na fim ɗin juriya na PCB. Idan kuna da wasu tambayoyi, ko kuma kawai kuna buƙatar tuntuɓar mu, koyaushe muna farin cikin taimaka muku.