Electronics Forum | Fri Mar 11 18:47:54 EST 2005 | davef
JD: It's important to note that FR-4 does not contain PBB or PBDE. The bromine in FR-4 epoxy comes in the form of tetra-bromo-bisphenol A [TBBA], which polymerizes and become part of the cross-linked epoxy. Bromine, in the form of hydrogen bromide, i
Electronics Forum | Thu May 26 19:32:13 EDT 2005 | Mike Konrad
Three popular methods: Resistivity of Solvent Extract (ROSE) Test Method IPC-TM-650 2.3.25: The ROSE test method is used as a process control tool to detect the presence of bulk ionics. The IPC upper limit is set at 10.0 *g/NaCl/in2. This test is p
Electronics Forum | Wed Aug 17 13:57:27 EDT 2005 | ppwlee
We have encountered what appears to be mask discoloration after wave soldering. The areas of concern coincide with the areas that were exposed selectively by fixtures during wave soldering, dominated by one date code of PCB with a slightly different
Electronics Forum | Fri Oct 14 11:56:49 EDT 2005 | patrickbruneel
Mika, 1.) Is there a maximum board thickness where it would be almost impossible to get a decent hole fil? Answer: The thicker the board the further the solder has to travel and the more you depend on solderability of boards and components, machine
Electronics Forum | Wed Nov 16 18:44:54 EST 2005 | Mike F
A good board used soon after you receive it should not delam. If only a small percentage is doing that I urge you to do some more looking at the board quality while you do the baking. Do a search of the archives on baking boards, Dave F had some good
Electronics Forum | Fri Jan 20 11:44:40 EST 2006 | Mike Dolbow Atotalgps.com
I have seen 100% Matte Tin plating and a lot of Sn/Ag/Cu plating for gull wing parts. This is the most common type of plating. Also in a lead free process you will see that the very end Toe of the part will not flow. This is due to the metal being cu
Electronics Forum | Fri Mar 17 16:58:52 EST 2006 | mikecollier
We are currently struggling with a particularly difficult component selection form our designers. This is a custom BGA, 592 balls, metal cover with a very large bead of adhesive using to retain the cover. We have had significant fallout (greater th
Electronics Forum | Tue Mar 28 08:29:04 EST 2006 | davef
Pad design - Standard IPC 20 pitch QFP Thermal pad design - Layout the thermal pad 0mm to 0.15mm larger per side (0mm to 0.30mm larger overall) than the exposed die pad on the package. �Larger than�, as opposed to the same size, is preferred. Obvio
Electronics Forum | Tue Mar 28 11:17:19 EST 2006 | smartasp
Thanks for the input Guys Yeah the not so knowledgable customer does not like to residues for cosmetic resons. The flux is for lead free process, of the no clean and water soluable type. We have explained to him that technically the residues do not
Electronics Forum | Thu Apr 20 22:46:26 EDT 2006 | samir
Amol, I thought I answered your question in another thread, dude! Anyway, to re-iterate. Yes, I was able to pull it off a hybrid profile. The LF BGA passed tensile testing, but no, it wasn't thermally cycled or stressed first to expose any latent
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