Electronics Forum | Wed Jul 02 12:42:58 EDT 2003 | slthomas
Not sure how else to describe this. We've received some boards (1/2" x 3.5" x .0325" board built on panels of 24) with numerous resistors showing separation of the solder from the metallization at the top of the joint. There are 26 0805's on the bo
Electronics Forum | Wed Sep 21 16:25:43 EDT 2005 | GS
IPC-7525 tells you how to make stencil apertures for BGA IPC-7095 tells you how much should be the paste volume in order to get a reliable BGA solder joint. How are your PCB finisced? (HASL, ENIG, OSP, etc?) In case of not HASL, it could be necessa
Electronics Forum | Mon Jul 01 13:19:55 EDT 2013 | emeto
I always look for a toe fillet if the design allows you to. Many times the pad design is close or exactly the size of the leads which makes people to touch it up right away. I told them hundred times not to but...Luckily I have 3D x-ray and I can tel
Electronics Forum | Tue Sep 20 17:39:52 EDT 2005 | russ
If the balls are eutectic (63/37) You shouldn't have any problems. All of our BGA rework is performed without paste. You have plenty of solder to make the joint with the balls themselves. Be wary of cleaning however since the standoff is less.
Electronics Forum | Wed Sep 21 01:57:40 EDT 2005 | hly
Hi K, Thanks for your reply. I was wondering if there is an industry spec that specifies a minimum required solder volume for BGA joints? Thanks HLY
Electronics Forum | Wed Oct 30 16:05:08 EST 2002 | msimkin
Hi, I have received a report form a board supplier, analysing the reuslts form non wetting problems we have been expereincing with their boards. I assumed it was due to the gold layer being too thin, thus allowing the nicklel layer to be exposed and
Electronics Forum | Fri Dec 12 11:52:59 EST 2003 | Marc Simmel
I have encountered problems with a 90/10 tin-lead plated SMT component wicking all the solder paste off the pads on the substrate. Worst, the defect occurs randomly - adjacent leads may have 'good' joints, though heel fillets are poor. The solder pa
Electronics Forum | Fri Jan 15 13:35:03 EST 1999 | Terry Burnette
| I saw the problem of void in solder bump or in lead less component or some BGA. But I didn't have standard specification of that void is accept or reject? Do any body have the better idea or suggestion of the criteria ? | | Thank you, | Wirat
Electronics Forum | Fri Aug 06 10:27:05 EDT 1999 | Kenneth Hedman
| | I saw the problem of void in solder bump or in lead less component or some BGA. But I didn't have standard specification of that void is accept or reject? Do any body have the better idea or suggestion of the criteria ? | | | | Thank you, |
Electronics Forum | Tue Sep 20 17:09:14 EDT 2005 | hly
I have a situation with hot boards with fine pitch BGAs that I need to build. However, there is a big problem--the auto screen printer is down. I decided that we would use the stencil and manually line up the pads and do a manual print. I can't ac
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