Electronics Forum | Mon Dec 22 12:06:27 EST 2008 | evtimov
Hi, it seems like a glue problem to me. If you don't have enough glue on SOT23, you have no contact and the part is holded only by the paste, which results bad in the waver machine. So first I would check is the glue amount under the SOT. The second
Electronics Forum | Mon Nov 21 10:51:12 EST 2011 | scottp
I've never seen a good article with a definitive explanation - just speculation that the increased wetting forces due to nitrogen result in increased tombstones. My own experience is that nitrogen is a very minor contributor to tombstones and can pr
Electronics Forum | Mon Jul 28 16:48:54 EDT 2008 | pcbbuilders
my oven has a built in profiler, it works fairly well, but it can not predict changes. my main concern was about the time right before reflow. i know that's where the flux is activated and i was worried that i may be spending too much time at the tem
Electronics Forum | Fri Aug 01 21:10:35 EDT 2008 | leo_dektec
You can keep only the 5th zone as the reflow zone. And lower the first two zones to keep a good ramping rate. Meanwhile,please note the ting temperature in software or control panel is not the exact temperature in your PCB, you'd better get a KIC or
Electronics Forum | Sat Aug 02 08:06:11 EDT 2008 | pcbbuilders
Is there a limit to the time that most components can stay at temperatures around 130-200 deg c? if i slow the time, the first 4 zones will be at this temp for about 5 minutes in no lead process. i am concerned that some chips wont be rated at this t
Electronics Forum | Tue Jul 06 19:45:03 EDT 2004 | ANDREW
Based on the attchment it looks like both are low profile and cater for high IO point.What are the challenges in running this 2 type of component?Is there any additional process required other than normal SMT for these 2 packages,like underfill ?
Electronics Forum | Wed Dec 24 20:29:45 EST 2008 | xianhua_tang
Oh,I consider the process is wrong,it is stencil print paste-mount-reflow -apply glue-reflow,then wave solder. it must pass twice reflow,also the first reflow profile is different and the second .
Electronics Forum | Mon Apr 09 21:09:29 EDT 2012 | isd_jwendell
I haven't worked with anything as small as 01005s, but something you didn't mention is the %metal of your paste. I just switch from 90% to 89.5% (AIM NC257-2) and could tell the difference. Just an idea...
Electronics Forum | Mon Apr 09 21:20:59 EDT 2012 | action_101
Interesting thought. Our paste is 89.2% according to the data sheet I have, but it still might be worth trying the 84-86% syringe blend. Thanks for the suggestion.
Electronics Forum | Fri Apr 13 12:31:23 EDT 2012 | markhoch
*Like* (There should be a way to "Like" or "Dislike" replies so that other Engineers can agree or disagree with a response. Doens't this sound like a good idea?)
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