A zabi na PCB surface shafi fasahar for SMT soldering a SMT aiki yafi dogara da irin na karshe tara aka gyara, da surface jiyya tsari zai shafi samar, taro da kuma karshe amfani da PCB. Wadannan a takaice gabatar da zabin tushen PCB solderability surface shafi.

Lokacin zabar abin rufe fuska na PCB a cikin sarrafa facin, zaɓin abin da aka zaɓa da kuma amfani da samfurin yakamata a yi la’akari da shi.

1. Solder gami abun da ke ciki

Dacewar PCB kushin shafi da solder gami ne na farko factor a zabar PCB solderable surface shafi (plating). Wannan kai tsaye yana rinjayar solderability da amincin haɗin haɗin haɗin gwanon a bangarorin biyu na kushin. Misali, Sn-Pb ya kamata a zaɓi daidaitawar iska mai zafi don Sn-pb gami, kuma za a zaɓi daidaitawar iska mai zafi don ƙarfe mara gubar ko kayan kwalliyar da ba ta da gubar.

2. Abubuwan dogaro

Kayayyakin da ke da buƙatun dogaro da yawa ya kamata su fara zaɓar matakin iska mai zafi iri ɗaya kamar gariyar solder, wanda shine mafi kyawun zaɓi don dacewa. Bugu da ƙari, ana iya la’akari da Ni-Au (ENIG) mai inganci, saboda ƙarfin haɗin haɗin haɗin haɗin Ni3Sn4 tsakanin Sn da Ni shine mafi kwanciyar hankali. Idan ana amfani da ENIG, dole ne a sarrafa Layer Ni don zama> 3 µm (5 zuwa 7 µm), kuma Layer Au dole ne ya zama ≤ 1 µm (0.05 zuwa 0.15 µm), kuma dole ne a gabatar da buƙatun solderability ga masana’anta.

3. Tsarin masana’antu

A lokacin da zabar PCB solderable surface shafi (plating) Layer, da karfinsu na PCB kushin shafi Layer da masana’antu tsari ya kamata kuma a yi la’akari. Matakan iska mai zafi (HASL) yana da kyakkyawan walƙiya, ana iya amfani da shi don walda mai mai fuska biyu, kuma yana iya jure waldi da yawa. Duk da haka, tun da saman kushin bai isa ba, bai dace da kunkuntar farar ba. OSP da tin immersion (I-Sn) sun fi dacewa da taro mai gefe guda da tsarin siyarwar lokaci ɗaya.