Electronics Forum | Thu Jul 22 22:18:12 EDT 2004 | davef
Notes from an AIM No-Lead Presentation ... Wave Soldering * May require a higher pot temperature than tin/lead: 255-265*C * May require a change in liquid fluxes to compensate for the poor wetting of some alloys and high thermal stresses of the wave
Electronics Forum | Mon May 16 22:59:40 EDT 2005 | davef
We believe your problem is caused by the mismatch in CTE of the material ised in your BGA. In fact, this "potato chipping" [where the corners curl-up] is present in all BGA. The issue is the matter of degree. [Mismatching CTE is how old thermostats
Electronics Forum | Fri Feb 10 15:14:08 EST 2006 | Chunks
Establish a profile board. It should be representative of what you normally run on a daily basis, size and parts wise. Attach dedicated thermalcouples so they are permanent and will not move or come loose. High temp solder is best. Establish a pr
Electronics Forum | Tue May 23 21:14:22 EDT 2006 | davef
First, where the temperatures that aare mentioned in the original post measured? Second, it sounds like the PdAg component terminations are not seeing enough heat [your soldering iron touch-up proves this]. Your 232*C peak is the absolute minimum s
Electronics Forum | Fri May 26 21:25:52 EDT 2006 | mika
Yes we do place "big and heavy" SMT DC/DC:s on most of our board's. Please tell us what brand it is or at least what the package look like?!? For instance we place a different numbers of "heavy" DC/DC converters (40x20mm & 45x25mm) that has the pick-
Electronics Forum | Sun Jan 14 12:42:35 EST 2007 | SMTRework
I think the main cause of this condition is #3 because both #1 and #2 never change from board to board, these are identical boards with identical BGA revisions. These BGA's (as stated before) are about 3 years old.. I don't believe they are lead free
Electronics Forum | Fri Feb 09 11:48:09 EST 2007 | realchunks
0.25mm tilt? That's pretty small depending on you BGA size. Is it failing? Or just your Q.E. being anal? What size BGA we talking about? What ball count? Just one board? Maybe cheaper to just repair. Now assuming there is NO part under the BGA
Electronics Forum | Thu Apr 19 08:50:38 EDT 2007 | rgduval
Welcome to RoHS. Or, at least, to the version of RoHS that I've had to deal with since I started with my current company. Blowholes and pinholes seem to be common in PB-free manufacturing. At least, they have for me here. I also note that IPC has
Electronics Forum | Tue Jul 17 21:48:09 EDT 2007 | davef
Per ESD Handbook TR 20.20 paragraph 5.3.15 Humidity "Humidity is beneficial in all ESD Control Program Plans. Contact and separation of dry materials generates greater electrostatic charges than moist materials because moisture provides conductivity
Electronics Forum | Mon May 12 17:59:55 EDT 2008 | rgduval
We're currently experiencing a spate of solder not wetting to pads of PCBs, and it's becoming more aggravating on a daily basis. At this point, we're running out of ideas. I've searched the Fine Archives for information, and, so far, haven't found
