Hi All!

(munch, munch...GULP) 'Scuse me, typing this email while I'm chowing down some lunch.

We just recently built some boards here that have a handfull of SOD323 packaged Schottky diodes from International Rectifier on them, and have had a pretty serious problem with the part and pads being ripped off the board. It's been happening mostly during hand cleaning.

We have a open cased DC/DC converter that we have to hand solder, and then hand clean. No, we can't use no-clean flux and leave the residues, the customer won't allow it. But that's where it seems they are getting ripped up. After the first couple of diodes got ripped up, we've made it known to the operators who are working on these assemblies how easy it is to do this, and that they need to be very careful when cleaning. We've got our best operators working on these assemblies, and I know their skills. But even when they try to be as careful and gentle as they can cleaning the assemblies, parts are still getting ripped-up...it's really unbelievable how fragile this part is.

Has anybody had similar experiences with this part?

I've got pictures of things on my page. Go and look at:

http://www.stevezeva.homestead.com/files/SOD323.jpg

There you will see a picture of the part. The part is kind of tall in relation to the size of the two pads it gets soldered to.

Now look at:

http://www.stevezeva.homestead.com/files/InternationalRectifierFootprint.jpg

There you will see what International Rectifier recommends for a footprint...pretty small pads huh?

Now look at:

http://www.stevezeva.homestead.com/files/footprintForSOD323.jpg

This is what I measured the footprint to be from the gerber for the board. The pads are a little undersized from what International Rectifier recommends, and they also are oriented 90-degrees out from the recommended footprint, but do you think that difference explains why these things are so easy to damage? Would you go with larger pads than what is recommended to provide more surface area for the pads to provide more mechanical strength to them?

Just curious if anybody else has had the same problems..

-Steve Gregory-

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