Electronics Forum | Thu Jun 30 03:14:34 EDT 2016 | andrzej
Looks like "black pad" issue. More about this here: http://www.ipc.org/feature-article.aspx?aid=Black-pad Definitly PCB supplier need to improve the process.
Electronics Forum | Wed Aug 24 22:11:36 EDT 2016 | davef
I'd guess that "black pad" is not the issue that you need to address, because only 2 of your 5 test points has the problem that we seem to be discussing. I'd expect "black pad" problems to be more wide spread. Something is going on at those two locat
Electronics Forum | Mon Aug 29 08:44:57 EDT 2016 | jrrt_williams
As an OEM repiar tech I would run into "Black Pad" on occasion, though mostly on surface mount pads. The only way I could remove the oxidation was to apply water soluble flux and add solder, then wick away the excess. This left me with a suitable s
Electronics Forum | Tue Aug 02 15:03:37 EDT 2016 | davef
On a previous black pad experience we soldered a wire to a fiducial and did a pull test to failure. On the black pad board the wire and solder pulled of clean leaving the fiducial on the board. On good boards the copper came off with the wire. If you
Electronics Forum | Mon Aug 22 22:40:52 EDT 2016 | twhoo
analysis report is as attached. Pls let me know what you think of the root cause of this issue? Can i conclude this is a black pad at thru hole ring with a root cause of contaminated gold
Electronics Forum | Mon Jun 27 11:01:58 EDT 2016 | mufflerbearings
From the pic, it looks like you have a bad board; ENIG process issue. It used to be called black pad for SMT but I'm sure it's the same condition for T/H. Any good electronic lab should be able to id the black stuff. I would also send raw boards bac
Electronics Forum | Tue Aug 02 15:02:50 EDT 2016 | davef
ASPIS (Advanced Surface Protection for Improved Reliability PCB Systems) The three year Aspis ‘Research for SMEs’ project has been conducted to address problems found with the nickel gold (ENIG) solderable finishes that are used by the electronics in
Electronics Forum | Mon Feb 19 22:56:20 EST 2007 | davef
Russ We agree with your comments on plugging from one side only. But... We believe that it IS possible to trap process chemicals [technically, not flux] in a blind [or any other] via. This can be done by plating the via closed, rather than pluggi
Electronics Forum | Wed Mar 19 19:02:39 EST 2003 | Jodi Roepsch
From my experience, we have had little success in reworking boards with the black pad condition. In one instance, with several reworks, we were able to get plated through holes with the defect to take solder but the joint reliability was highly ques
Electronics Forum | Tue Sep 25 14:08:59 EDT 2001 | davef
Oooo, the solder on the pad and PGA ball is flowing during reflow down the via to the secondary side? Why didn�t you say so?? ;-) Why would you expect that gravity and capillary action wouldn�t force solder to flow down the solder plated via to the
