Electronics Forum | Tue Apr 17 16:34:25 EDT 2018 | slthomas
I attributed it to luck, but whatever keeps you up and running!
Electronics Forum | Tue Apr 10 10:21:06 EDT 2018 | slthomas
Dave, that's a cool idea and sounds like something that would actually work. I'd be tempted to go with oversized pads to increase the holding force. Unfortunately as an EMS we would have to work that through the customer approval system and as usual
Electronics Forum | Tue Apr 10 10:33:08 EDT 2018 | davef
Oh, I just remembered the other thing that I wanted to mention ... Do the pads match the component leads?
Electronics Forum | Wed Apr 11 11:55:54 EDT 2018 | slthomas
Yes - every dimension that I measured on the gerbers checks out against datasheet. Presumably the parts match it as well....?
Electronics Forum | Mon Apr 16 16:24:20 EDT 2018 | slthomas
Amazingly enough, every one of these held fast where we placed them with a paste brick sized 1:1 with the thermal pad, no sectioning. Yes, there were voids, but we can live with that in this application.
Electronics Forum | Wed Apr 18 14:17:48 EDT 2018 | esoderberg
Further divide the ground block into more than 4 panes. Also think about using, assuming you have good placement of using Loctite chip bonder on two opposing corners. Lots of ways to get good results
Electronics Forum | Mon Apr 09 16:00:46 EDT 2018 | slthomas
Yes. I'm at a loss as to how to best approach this. I think the giant blob of solder is just going to behave more like a lubricant than anything else. The thing is, I would like to at least try the manufacturer's recommendation once (and this bui
Electronics Forum | Tue Apr 10 08:37:36 EDT 2018 | davef
Hi Steve ... I found nothing in the manufacturers "paper" to help. Comments are: * I agree. No blobs. Solder on the thermal pad should me minimized. Too much solder will float the component. Old timers used to talk about 50-80% coverage. * If you'
Electronics Forum | Wed Jul 18 17:09:45 EDT 2018 | slthomas
Update - next run started out horribly so went to another stencil design. Reduced thermal pad coverage by about 40% with 4 panes, with cutouts to avoid the vias. Worked like a charm for 10 boards (90 parts). I think we're finally on to something.
Electronics Forum | Mon Apr 09 13:53:45 EDT 2018 | dleeper
I've never placed one of these before, but it looks like a poorly designed part. It has pads scattered asymmetrically around the body of the part. when it reflows this is going to apply uneven forces to the component, causing it to skew. I guess hav
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