Electronics Forum | Tue Dec 15 12:23:47 EST 2009 | swag
I have moved golden boards from chains to mesh as I got tired of fishing t-couples under the chain rail. I saw a 3-5 deg. decrease on top-side parts peak temp. (all t-couples were on top side). I had to bump zones 6 and 7 a few degrees to make up f
Electronics Forum | Sat Mar 27 03:57:09 EDT 2010 | grahamcooper22
I agree with Steve. Your are too hot and too hot for too long. What is the device spec for Peak Package Temperature (PPT)? (this is usually on the moisture barrier bag) Many leaded BGAs have PPT of 225 Deg C. Even if it is higher, like Steve suggeste
Electronics Forum | Mon Apr 19 11:04:21 EDT 2010 | baildl632
We have had some unusual reflow conditions with BGA's as well. We did not come to the conclusion that something was covering the lands though. It typically occured with only the BGA lands (not the decoupling caps on the back side). We found that the
Electronics Forum | Thu Aug 19 05:19:31 EDT 2010 | grahamcooper22
I have seen that moisture in pcbs will cause mid chip solder balls. To discount this, take one pcb from a batch that is giving you solder balls and pass it through you reflow oven with no paste or components on (bare pcb)using your normal reflow prof
Electronics Forum | Thu Apr 07 12:02:08 EDT 2011 | grahamcooper22
Clearly you are above liquidus for too long so you can either increase conveyor speed or lower some zone settings. With your current recipe you don't mention the conveyor speed or the total profile length. Also ...are your max / min slopes really so
Electronics Forum | Tue Dec 13 17:41:04 EST 2011 | davef
A Study Of 0201’s And Tombstoning In Lead-Free Systems, Phase II Comparison Of Final Finishes And Solder Paste Formulations http://sheaengineering.com/Documents/APEX%2008%200201s%20and%20Tombstoning%20phase%202%20paper.pdf CONCLUSION The condition
Electronics Forum | Tue Jun 05 07:07:57 EDT 2012 | mosborne1
You should just be running you Kic or Mole to verify the process.Every new board should be profiled. Once have verified the process there should be no reason to keep prifiling the boards. Your QA dept should be inspecting the solder joints. If there
Electronics Forum | Thu Dec 27 13:04:58 EST 2012 | dyoungquist
From the temps you list, I'm going to assume you are using leaded solder. What type of oven profile are you using: Ramp-Spike or Ramp-Soak-Spike? I think you will have better results if you use the Ramp-Soak-Spike type of oven profile. Better chan
Electronics Forum | Thu Sep 19 11:02:17 EDT 2013 | hegemon
If there is only a single lead free BGA on the BOM, I would suggest a "hybrid" profile. Use regular solderpaste (SN63/pb37) and peak your temperature at around 225C. Allow a bit longer TAL to let the two solders co-mingle at the BGA joints. You are
Electronics Forum | Tue Nov 05 09:57:45 EST 2013 | cuperpeter
Hello All, We have a problem with dewetting of solder paste. Problem is most visible on the pads without components (see attached pictures) and occurs randomly, 20% of PCB's. Pcb supplier sent us a cross-section of pads with thickness of Cu, Ni and
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