1. I-PBGA idityaniswe kwiUmatshini we-SMT, kunye nenkqubo dehumidification ayiqhutywa phambi ukuwelda, okubangela umonakalo PBGA ngexesha welding.
Iifom zokupakisha ze-SMD: ukupakishwa okungangeni komoya, kubandakanywa ukupakishwa kweplastiki ye-pot-wrap kunye ne-epoxy resin, i-silicone resin packaging (evezwe kumoya we-ambient, umswakama we-polymer materials).Zonke iipakethi zeplastiki zifunxa ukufuma kwaye azitywinwanga ngokupheleleyo.
Xa i-MSD ibonakaliswe kwindawo ephakamileyoreflow ovenubume beqondo lobushushu, ngenxa yokungenwa kwe-MSD ukufuma kwangaphakathi ukuba ngumphunga ukuvelisa uxinzelelo olwaneleyo, yenza ibhokisi yeplastiki yokupakisha ukusuka kwitshiphu okanye isikhonkwane kwi-maleko kwaye ikhokelele ukudibanisa umonakalo we-chips kunye nokuqhekeka kwangaphakathi, kwiimeko ezinzima, ukuqhekeka kunwenwela kumphezulu we-MSD. , nokuba kubangele ibhaluni ye-MSD kunye nokugqabhuka, eyaziwa ngokuba yi-"popcorn" isiganeko.
Emva kokuvezwa emoyeni ixesha elide, ukufuma okusemoyeni kuyasasazeka kwisixhobo sokupakisha esingena amanzi.
Ekuqaleni kwe-reflow soldering, xa iqondo lobushushu lingaphezulu kwe-100 ℃, ukufuma komphezulu wamacandelo kukhula ngokuthe ngcembe, kwaye amanzi ngokuthe ngcembe aqokelelana ukuya kwindawo edibeneyo.
Ngethuba lenkqubo ye-welding ye-surface mount, i-SMD ibonakaliswe kumaqondo okushisa angaphezu kwe-200 ℃.Ngexesha lokuphinda kweqondo lokushisa eliphakamileyo, indibaniselwano yezinto ezinjengokwandiswa kokunyakama okukhawulezayo kumacandelo, ukungahambi kakuhle kwezinto, kunye nokuwohloka konxibelelwano lwemathiriyeli kunokukhokelela ekuqhekekeni kweepakethe okanye ukuchithwa kwezinto kwiindawo eziphambili zangaphakathi.
2. Xa ukuwelda amacandelo ilothe-free ezifana PBGA, isenzeko MSD "popcorn" kwimveliso iya kuba rhoqo kwaye nzulu ngenxa yokwanda ubushushu welding, kwaye nkqu ukukhokelela kwimveliso ayinakuba yinto eqhelekileyo.
Ixesha lokuposa: Aug-12-2021