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 | Wed Mar 10 17:03:52 EST 1999 | Morziana Hasan
NASA CommQuest Photopolymerized Conducting Polymers Directions: 1.Please read the information provided on this technology. You may follow the links to additional information resources below. 2.After evaluating the technology, please answer the
Electronics Forum | Sun Aug 08 11:15:32 EDT 1999 | Earl Moon
| | Mike, | | | | Got your message and those of others concerning PCB fab supplier evaluation and qualification check lists, etc. I have a severe problem here in WI as I can hardly access the internet, and when I do it is cut off abruptly for no goo
Electronics Forum | Tue Nov 29 21:51:37 EST 2005 | wmeyers
I have a pin and sleeve assembly that utilizes a fusible link type of solder, Bi, Cd, Pb and Sn alloy. The pin is gold plated, the sleeve is copper alloy 725. I have had sporadic success with wetting of the sleeve during the reflow process. To improv
Electronics Forum | Sat Nov 14 08:05:54 EST 1998 | Earl Moon
| | | | I believe that gold fingers on my circuit boards are being | | | | contaminated and need to clean them with some chemical | | | | solution. Any recommendations. | | | | | | | Chuck: What is the type and source of your contamination? Dave
Electronics Forum | Mon Apr 27 14:39:38 EDT 2015 | davef
Anirudh: When board fabs talk "surface finishing" they're talking about the solderability protection that you'd like on the solderable copper component mounting pads that you laid-out for each component: * Bare copper pads corrode very quickly * Corr
Electronics Forum | Fri Aug 30 16:25:21 EDT 2002 | davef
Imm silver holds-up to multiple thermal cycles very well. The things, we guess, are happening to make imm silver tough to solder after heating and sitting are: * Oxidation of the silver. * Reduction of the co-deposited organic anti-tarnish [used in
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 Jul 15 19:05:58 EDT 1999 | Earl Moon
| | | We have been encountering diminishing ball shear readings these past few weeks, despite the fact that we did not change any ball shear tester parameter. Our reflow parameters are also within spec limits. ( 210-220 deg C max temp. and 40-60 sec
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
