Electronics Forum | Thu Dec 01 14:42:57 EST 2005 | Amol Kane
my first thought was that too, but all the other components on tha board have reflowed properly. I have tow test boards, one with Imm Sn and other with Imm AG. on both these boards only the QFP has this solder phenemenon
Electronics Forum | Fri Aug 30 04:44:31 EDT 2002 | jason
Hi Dave, Why does it become " a bear" if u leave it unsoldered ?? Does it oxidise or something ?? Question (1): Does Ag imm. PCB need to use Solder paste with AG ?? If yes, why. Question (2): Does Ag imm pcb have poorer surface finishes than HAS
Electronics Forum | Fri Feb 03 13:17:10 EST 2006 | amol_kane
also as an aside, make sure that the Imm Ag boards are stored in sealed bags with silver saver paper between 20-25 deg C and 40-50 % RH
Electronics Forum | Mon Feb 06 13:00:51 EST 2006 | amol_kane
Hi all, I just wave soldered 40 boards (20 if Imm Sn and 20 of Imm Ag) using SAC 305 (in this case the wave machine manufacturer (electrovert) suggested the alloy too). plan to carry out x-sectioning to see the results. overall, just from the visual
Electronics Forum | Wed Aug 27 18:28:29 EDT 2008 | blnorman
We have an immersion silver board that has a brown discoloration after processing. It's not flux residue, that normally doesn't cause this condition. Elemental analysis shows less than 1% sulfur, and I thought silver sulfide is more a black color.
Electronics Forum | Tue Sep 02 16:07:04 EDT 2008 | blnorman
Colorization is relatively uniform across the board. "Processing" is first pass reflow. I belive MacDermid is the ImmAg supplier. Plating thickness has not been determined, our XRF is being revitalized. Elemental analysis did show a large copper
Electronics Forum | Tue Jul 27 07:06:59 EDT 2004 | davef
HASL Thickness: * HADCO DFM manual specifies a nominal thickness of 50-1500uin with an option for 100-1000uin * Merix DFM manual specifies 30-200uin * Our boards (from a major fab) average 500uin with an "as measured" range of 300-800uin Be careful
Electronics Forum | Thu Dec 18 15:48:25 EST 2003 | Subhash Nariani
Hello, Does anyone have experience with the PCB assembly of 0.5mm pitch chip scale packages with HASL finish? Characterization data that you can share? Tribal knowledge has it that the height variations of the solder prevent the use of HASL for fin
Electronics Forum | Thu Jan 12 11:06:27 EST 2006 | muse95
No not really. They are inspected with gloves, but all PCB's are in our facility, no matter what the finish. They are stored in the same packaging material that they are shipped in. We haven't been using ImmAg for that long yet, so maybe we will se
Electronics Forum | Thu Aug 29 17:51:43 EDT 2002 | nifhail
I have seen several Imm Ag pad on the assembled board which have a copper colorleaching through the silver plating This happened on the pad which was not deposited with paste during the assembly process. Don't know if it is a problem, but we only h
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