Electronics Forum | Tue Mar 13 20:25:39 EST 2001 | davef
So, what is not soldering? Pads er test points? I assume the holes are unsupported, right? Tell us more about the test points. Are they the kind with the little pastic shoulders [on the primary side] that keep them from falling through the hole?
Electronics Forum | Tue Mar 13 11:50:21 EST 2001 | gsmguru
Here is some general things I usually ask myself when having trouble with BGA's What type of BGA ? Pitch/Bump Dia etc. Smaller bumps sizes & tighter pitches require more attention. This also impacts stencil aperature design & paste selection. Was
Electronics Forum | Wed Mar 14 18:29:04 EST 2001 | mparker
The basic rule of thumb (info current as of 9/2000, from Ceeris and others) is the 10X multiplier for each major process step. Catching a defect and correcting in SMT will cost $0.10 each. (think about $.04 placement cost, stop line time, operator h
Electronics Forum | Fri Apr 06 08:35:20 EDT 2001 | brownsj
You can buy plenty of paste height measuring systems today, ranging from full 3D laser systems to systems using an oblique light line which will measure the paste height only. I found that the lowest cost option was to attach a DTI to the focus contr
Electronics Forum | Fri Mar 30 13:06:50 EST 2001 | aortiz
Hi, I need support on the method or applicable standard to measure the shear force strength on chip capacitors and resistors. I know the soldered joints strength is related to land desing, solder volume, pcb and component solderability, component
Electronics Forum | Fri Apr 20 11:07:52 EDT 2001 | kawiederhold
Hi Dave, Good to "talk" to ya again!! I have attached a photo of the antenna. Hopefully it will work its way through the system. The pictured antenna meets all our criteria. The defective antennae all seem to slide toward the center of the PCB (
Electronics Forum | Mon Jun 11 14:25:36 EDT 2001 | CPI
I had the very same problem but, did not question my oven as I knew the profile was good and I should have had even heating. So I then looked at pad size and layout. When Layout and size were found to be ok. I attached a prob to each pad and ran a pr
Electronics Forum | Mon Jun 11 22:00:19 EDT 2001 | davef
IPC-A-610 uses words to the effect that it�s a Class 2 process indicator, if either: * Entrapped or encapsulated solder balls that are within 0.13 mm [0.00512 in] of lands or connectors, OR * Entrapped or encapsulated solder balls exceed 0.13mm [0.00
Electronics Forum | Tue Jun 26 12:24:24 EDT 2001 | nifhail
Thanx for the reply Dave. We actually had a few thermocouples attached from underneath to see if there is any delta in temperature within the same BGA's ball. They looks OK, with the slope of 1 -2 Deg C,soak at 120 Deg C - 150 Deg C at about 90 sec,
Electronics Forum | Mon Jul 16 21:44:07 EDT 2001 | davef
You�re correct. If you attach $5 to each board, your customer will be happy to approve your process change. Consider: �Process Improvement Strategies: Implementation Of A No-Clean Process" http://www.smta.org/knowledge/proceedings_abstract.cfm?PRO
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