Electronics Forum | Mon May 26 03:27:00 EDT 2014 | julianf
Thanks for your reply Sarason. I'm aware now that my goals seem very ambitious and infeasible. Let me formulate my problem in an different way that might be more realistic. Is it possible to measure a DIFFERENCE in strain between top and middle la
Electronics Forum | Wed May 14 10:20:37 EDT 2014 | julianf
Hello all! For my mechanical engineering study I want to etch a strain gauge in the Wheatstone bridge configuration in a copper layer of an PCB. The goal is to measure the strain occurring in an PCB even during the press process! We can measure with
Electronics Forum | Sat Jul 25 08:47:25 EDT 2009 | davef
Both "moisture content of bare board" and the "thickness of the copper plating in the PTH" are related to each other. As you heat the solder connection, moisture in the board boils and out-gasses through the solder connection. Plating with the proper
Electronics Forum | Fri May 13 14:08:39 EDT 2011 | eezday
This appears to be black-pad and is often the result of using specs that call for gold plating that is too thick. The black pad is corrosion that is created between the gold and electroless nickel during the gold plating process. This is counter in
Electronics Forum | Thu Apr 20 22:14:51 EDT 2006 | raquel
hello! need ur inputs... if the Matte Sn pbfree finish of the component discolors AFTER having been exposed to bake, or, after reflow, will the base leadframe have any potential contribution to it? i know most likely suspects would be the plating pro
Electronics Forum | Fri Jul 24 23:20:11 EDT 2009 | umar
Hi Dave, Thanks on your feedback, May I know the how's the contributing of Moisture content of bare board and the Thickness of the copper plating in the PTH to the solder ball and solder splash during hand soldering process ?
Electronics Forum | Fri Jul 24 07:43:56 EDT 2009 | davef
Your customer is correct. You are doing something wrong in your hand soldering process. Solder balls are a process indicator. Areas to assess are: * Moisture content of the bare board * Thickness of the copper plating in the through holes * Temperatu
Electronics Forum | Mon Sep 17 02:56:40 EDT 2001 | mugen
Hi, (me been absent for some time...) Are your brds confirmed HAL over copper? (check out what Dave F mentioned abt possible root causes) or are the brds HAL over nickle? (shd be no problem here, if so?) or are the brds strictly nickle plated pads?
Electronics Forum | Sun Jul 26 07:52:35 EDT 2020 | sync40
Hello to everyone, Have you ever experienced soldermask bubbles inmediately after printed the soldermask itself? (for screen printing method of LPISM). I am not talking here about blistering or any outgassing defects after exposing to high temperatu
Electronics Forum | Tue Nov 07 21:49:05 EST 2000 | Dave F
Cheers to you Your gold plating is specified for the gold wire bonding between the die of your BGA and the pads on the BGA substrate. For solderable surfaces this is heavy on gold for use on pads. Gold SB thinner on pads to limit the amount of gol
