Electronics Forum | Tue Oct 26 08:41:56 EDT 2004 | Bob R.
When we first got into BGAs on ENIG we were getting joint cracking at in-circuit test. The joints were breaking in the Sn-Ni intermetallic. We did a lot of pull testing while working with our board suppliers and our conclusion was that pull testing
Electronics Forum | Wed Nov 17 10:03:29 EST 2010 | scottp
Instead of a minimum thickness, we require no exposed copper or SnCu intermetallic. We've been having a lot of trouble lately with suppliers of SN100 HASL boards giving us pads with very irregular solder deposits with areas of exposed intermetallic.
Electronics Forum | Tue Oct 09 14:30:32 EDT 2012 | bandjwet
Put on your Chemical Thinking Caps..... We are ablating the mask of a PCB which was over a copper layer. This exposes copper. Outside of an electrical test (no can do) how could we use a fast non-destructive test in order to determine that copper (
Electronics Forum | Mon May 14 17:12:20 EDT 2001 | davef
Continuing along the path that Brian took ... IPC-7525 gives design guideline for stepped stencils. It goes something like: * Stepped area SB GT 25 thou from pads located on the greatest thickness of the stencil * Pads in stepped area SB GT 35 tho
Electronics Forum | Thu May 18 03:15:32 EDT 2017 | wama
We are soldering wire 26AWG to jack socket. However after went through washing, baking, coating, curing processes the wire breaks (at joining point with jack socket) during wire dressing. We have tried to increase and decrease the solder amount but r
Electronics Forum | Fri Jul 23 06:48:23 EDT 2004 | mattkehoe
I am actually getting opinions that point to contaminated copper under the HASL finish. We've seen some "fish eyes" where the HASL is pulled away from the copper exposing a pin hole of copper that can be seen through the HASL finsh. We are planning o
Electronics Forum | Thu Mar 15 06:26:26 EST 2001 | Sal
Sorry for the lack of information provided, I'll try again : Test Points are the one's that are not soldering. The test points are round in geometry, 0.5MM(metric) in diameter with a HASL finish.The test point are no different to the ed through hole
Electronics Forum | Mon Jul 11 19:32:27 EDT 2005 | fctassembly
Yes, there have been many issues with the fast dissolution of copper by the SAC305 alloy. In fact, there are companies who have disqualified it for repair operations due to loss/thinning of the pads. SN100C dissolves copper much slower than SAC305 an
Electronics Forum | Thu Feb 21 17:19:08 EST 2008 | davemn
if you are not using them for test points or want them filled with solder for current carrying capability then tent them puppies. i was able to move our company away from exposed vias many years ago and this eliminated lots of hairline shorts between
Electronics Forum | Tue Jun 05 21:14:10 EDT 2001 | davef
You aren't going to post our stuff on your "Hey, I'm the wizard site", are you? Board fab, Pad coatings, OSP 1 OSPs: Imidazole (Via Systems) is good. Entek (Enthone) works, but requires strict thickness control in fab. 2 Enthone CU56 allows one t
