Electronics Forum | Tue Sep 01 10:16:10 EDT 1998 | Mike Cox
| | We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | | Our pad design is .020" diameter pads with .025" solder resist diameter. Th
Electronics Forum | Thu Mar 04 10:45:19 EST 2004 | Robert
My company is relatively small but we have a SMT line. However, we don't have a stencil cleaner so I resort to a spray bottle of denatured alcohol, wiping it with a cloth and then using a toothbrush to brush the apertures. Finally another wipe down a
Electronics Forum | Tue Dec 04 10:30:16 EST 2007 | slthomas
Q: The question I have is do they wet in wave solder, and if they do, why does it matter what happens to them in reflow? A: Yes, but somebody here don't agree with me that the glued part need help from wave to get the good wetting. They are wrong
Electronics Forum | Mon May 29 02:15:06 EDT 2000 | Dreamsniper
Hi Buddy, We've tried shifting to this process before and from our point of view here are some of the advantage and disadvantages that we discovered. Advantage 1) Cheap Equipment cost as you just need to use your Solder Paste Printer rather than buy
Electronics Forum | Thu Jul 20 14:52:05 EDT 2000 | Bob Willis
If you are talking about Pin In Hole Reflow that is not true, I hope it was not my friends at Speedline that told you that. Stencil printing of paste for through hole reflow can be done. If you get all the parameters right it can give you joints lik
Electronics Forum | Tue Jul 09 08:29:10 EDT 2002 | r_sturdevant
I agree with others here who have questioned the amount of solder and reliability of the joint when using this aperture shape. I have had experience with these with MELFS, and the main issue I've seen comes when cleaning the stencil - all those littl
Electronics Forum | Mon Nov 12 09:22:41 EST 2007 | devajj
BTW, The surrounded QFN fine pitch terminals > should have the normal aperture reduction of 7 % > in case of RoHS Senju solder paste. This works > for our Telecom customer. > > The vias in the > ground pad will be somewhat filled with solder >
Electronics Forum | Thu Apr 12 22:54:06 EDT 2007 | mika
conductor on the narrowest place ~0.07mm we suggest them to go for a PCB solder pad down to 0.30mm. The Conductor width is: 0.2mm The current problem they are having now is that there will be a problem with 14V to narrow the conductor to the narrowe
Electronics Forum | Fri Apr 20 11:05:23 EDT 2001 | gcs
Just a bullet! My results are, .005" stencil thickness should measure between .0055" - .006" if your pressure is correct, metal blades and snap-off is set up correctly. Do you have aperture reductions at the QFP locations "typicial industry standard
Electronics Forum | Thu Nov 11 05:30:09 EST 1999 | Wolfgang Busko
For me it sounds like to much paste. If it worked in former runs with the same design and stencil look for changes in your printing process, check the volume and shape of your deposit. Redesigning pads and playing with aperture size allowing for mor
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