Hey Alejandro!
The pic is up! Go to:
http://www.stevezeva.homestead.com
You having problems with those pesky film capacitors too huh?
We have been having problems with "drawbridging" and "tombstoning" with these puppies. From my point of view, the footprint is extremely critical with these guys, because they are so light, being plastic film. Wetting forces drive these guys crazy!
The situation that I'm dealing with now is with 0805 film caps. Have had numerous "Draw-bridges", and "Tomb-stones" with these guys.
Footprint is what I've figured is the problem...they've gotta be dead on. Got some prototype boards in here that reduces the gap between the pads, and we're gonna' run them to see what happens...let ya'll know what happens
Alejandro, don't want to scare you, but these film caps are very, very fragile!! We don't wave solder them here, but have had my inspectors come to me asking about the layers of film flaking off from them at final inspection. According to Panasonic, that's not a problem what-so-ever, it does in no-way affect the function, or reliability of the capacitor.
Ain't this stuff fun?
-Steve Gregory-
Hello to All,
We have had tombstoning in a Film Chip Capacitor (Size 1206).
It is being soldered in a normal reflow process, and this is the only component that it is showing tombstoning.
Reviewing the specs. of the component in the web I found that this capacitor is recommended for Wave Soldering.
Does anyone know the difference in construction between the Capacitors for Reflow and Wave Soldering?
Is it possible that this be cause for the tombstoning?
I am also sending pictures for cross section for the capacitors that we are using (Recommended for Wave Soldering).
They could be seen at Steve's site.
Regards
Alejandro Becerra
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