Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Film Chip Capacitor reflow problems

Views: 1498

james

#43825

Film Chip Capacitor reflow problems | 8 September, 2006

We are incurring problems with Film Chip Capacitors with reflow issues. Some of the parts are misaligning or not soldering on one end (almost tombstoning) . We left the parts in the dry cabinet till they were used. We tried both reflow ovens (heller and conceptronics), no difference. Just wondering if anyone else had the same problem and what you did to do to fix it. What do you suggest as fas as doing a solderbility test with paste. Our profile does not exceed 230 c. The part number is CF028b0473JBA, AVX, Made in France, Packaged in Czech Republic. We have 4 different part numbers that have issues and each are made in France. Right now, we put the job on hold until I research and figure out a solution. Thanks for any input.

reply »

#43826

Film Chip Capacitor reflow problems | 8 September, 2006

We had problems with Panasonic film caps with a previous employer. The first step was to use their recommended pad layouts rather than industry standards for the part sizes.

The second much more helpful resolution was to complain like hell to Panasonic about the lousy soldering we got with those parts, regardless of profiles, paste quality, print quality, placement accuracy, until they redesigned the parts. Apparently we weren't the only ones having problems.

reply »

GPP

#43830

Film Chip Capacitor reflow problems | 8 September, 2006

James,

What type of profile are you using. Ramp-to-Spike, Ramp-Short Soak-Spike, or Long-Low Spike?

I had a similar problem in a past life - random skews on chip components - and got rid of it by converting to Ramp-to-Spike (the old profile was Ramp-soak-Spike). We were using an old Kester paste as well, and their data sheet recommended RSS. I theorized that the problem was caused by uneven wetting forces...

My theory is that the RTS profile balanced out the wetting forces during reflow because there was activator preserved during the reflow zone of the profile from having a more gradual ramp rate.

reply »

james

#43836

Film Chip Capacitor reflow problems | 8 September, 2006

We are using Kester and it is RSS.

reply »

cuculi54986@yahoo.com

#43862

Film Chip Capacitor reflow problems | 11 September, 2006

Steve,

Let me guess, you were using this one: http://www.panasonic.com/industrial/components/pdf/abd0000ce10.pdf

That part sucks. They have a newer part number that is supposedly "reflow-friendly". Unfortunately, I can't convince our quality department to get one of two things done:

1. Change the part. OR 2. Change the pads to Panasonic's recommendation.

When the customer finally gets an unsoldered (tombstoned) capacitor, then they'll be all over it.

reply »

#43864

Film Chip Capacitor reflow problems | 11 September, 2006

1. Change the part. OR 2. Change the pads to Panasonic's recommendation.

Actually both are recommended from my perspective.

ECHU. Shudder.

reply »

Reflow Oven

reflow oven profiler