Electronics Forum | Fri Jan 21 05:18:55 EST 2000 | Dean
If at all possible avoid mirror assembly BGA designs. It has a higher failure rate when compared to non-overlap designs (life testing). In addition, from a rework point of view, X-ray inspection yields no help when a failure occures. You can't det
Electronics Forum | Wed Jan 19 11:37:18 EST 2000 | Mark D. Milward
Does anyone consider the use of a Cyberoptics LSM solder paste thickness measurement system to be a valid test in determining the viscosity of solder paste. This procedure was proposed as an alternative to using the Malcolm gage for viscosity testing
Electronics Forum | Wed Jan 19 17:01:18 EST 2000 | Chad Notebaert
You can buy desicant packs and indicator cards to place back in the original or a new bag with the BGA's and re-seal using a heat sealer (Vac Seal being the best). If properly done the material will be kept below the 20% RH level. Another option woul
Electronics Forum | Mon Jan 17 13:09:12 EST 2000 | Dennis _F
We seem to have voids show up in one out of 5 BGAs during x-ray inspection. The x-ray is set up to accept the joint with anything less then 30% void area. I need anyones input of what during the process we can do to decrease the voiding and/or a good
Electronics Forum | Mon Jan 17 18:36:26 EST 2000 | William
Voids can be acceptable @ 24% per 5 balls area, and 8% per single ball area. In fact, Proceeding Book 1996; Vol. I, Page #126 conclusions saids: that solder joint voiding at the maximun levels pbserved in this study (were voided area was up to 24 per
Electronics Forum | Thu Jan 20 11:20:28 EST 2000 | Brian W.
It sounds like what you are seeing is leaching of the end cap. You need to check the manufacturer's spec. Many components have terminal barriers, which get a solder plating. Sometimes this plating process is not done well, and the solder plating le
Electronics Forum | Tue Jan 18 09:48:26 EST 2000 | Clifford Peaslee
Also try deleting your SMTnet cookies. I believe there may be a problem with the cookie itself. We also may force a user wide logout, in order to make sure that everyone's cookie is ok. By doing that, we would automatically delete the cookie on your
Electronics Forum | Fri Jan 14 16:21:42 EST 2000 | Dave Chapman
We are having mid chip solder balls on chips and resistors. Seeing the problem on 80% of the assemblies we run. Anywhere from 1 to six of the balls per board. We have slowed the oven down, increased the pressure on the screenprinter to get less paste
Electronics Forum | Fri Jan 14 16:22:05 EST 2000 | JAX
The feeders that you are probably refering to are made by hoover-davis. They only have adjustable pitch( electronic ). You probably will not find a universal feeder that has adjustable width. This is because the guide track is positioned on the left
Electronics Forum | Fri Jan 14 08:09:20 EST 2000 | Wolfgang Busko
We are using frameless stencils with a frame system tensioning in X- and Y-direction. After first quarrels with our stencilhouse about the correct position of the tensioning holes ( they needed 4 tries to get it right) there are no problems any more.
