Electronics Forum | Fri Jan 07 10:27:07 EST 2011 | patrickbruneel
Hi, Detergent/saponifiers have indeed the potential to tarnish aluminum. This is due to the high alkalinity of the chemistry (pH 10-12). Things you can do to minimize the effect is: A) Limit the exposure time of the Al with the chemistry. B) Reduc
Electronics Forum | Thu Aug 23 15:45:48 EDT 2001 | slthomas
So, we've already addressed the tombstoning on these guys by adopting the mfr's (Pana.) recommendations for pad size and spacing. Problem is, we have pretty bad wetting of some of these parts. The rest of the board we use them on looks great, nice
Electronics Forum | Wed Sep 19 10:38:58 EDT 2012 | mark25y2001
It's both solderpaste or PCB pad problem... 1st it's possible that your PCB exposure problem or old stocks, remedy? try to bake your PWB. 2nd, it's possible that PWB coating (wax) are more ticked so that solder paste flux are cannot penetrate to clea
Electronics Forum | Mon Sep 22 16:00:43 EDT 2003 | Joe
Two BGA replacements (same location) and throw the card away is the rule we are following. Experience has taught us that anything beyond this and you'd be pushing it - specifically when your new PBGA's price is above $20.00. The biggest concern is
Electronics Forum | Wed Oct 03 19:28:58 EDT 2012 | rgduval
Given that you're seeing it on nearly every part, we tend to lean towards Dave's explanation. We wouldn't expect outgassing from the pad to be an issue (at least, we've never heard of it before, which doesn't, necessarily, eliminate it as a potentia
Electronics Forum | Tue Nov 28 21:07:44 EST 2000 | Alvin K
Gold is porous and spots on gold plated PCBs is one of the drawbacks of using gold as a solderability protector. Base Nickel exposure seems to be the cause of this and is aggravated when the gold thickness is less than what it should be. I agree with
Electronics Forum | Fri Aug 06 10:07:50 EDT 2004 | blnorman
OSP has limited elevated temperature exposure capability. Couple that with the fact that solvents (IPA in particular) will remove the OSP. The more material you loose the higher the chances for pad oxidation. We ran an experiment with board washin
Electronics Forum | Thu Nov 15 10:33:35 EST 2007 | paulallan
Does any one know of a supplier high temperature PCB ink that can safely used between pads on an SMT connector. The product ideally should be screened on and have resistant to short exposure to heat from a selective lazer. Must be non-conductive and
Electronics Forum | Wed Aug 27 13:50:57 EDT 2014 | mcapizzi
The superior machines typically use only a split vision system which allows two pictures to be viewed simultaneously. The PCB (pads) and the underside (balls) of the BGA can be observed. By using micrometer screws, both exposures can be adjusted exac
Electronics Forum | Fri Oct 26 17:01:52 EDT 2001 | davef
We process no Teflon boards. Companies, such as Rogers and Taconic, make laminates of Polytetrafluoroethylene [PTFE] er �Teflon�. Common �Teflon� laminates are: * Woven glass / PTFE * Random microfiber glass / PTFE * Ceramic / PTFE * Woven glass /
