Electronics Forum | Wed May 03 13:34:04 EDT 2023 | proceng1
When we get a bad print at SMT, the operator uses the alcohol wipes and wipes the paste off the board. Then they use compressed air and another wipe. In most cases this is sufficient. Most vias are tented, but there still remains some solder sphere
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
Electronics Forum | Fri Sep 11 09:45:39 EDT 1998 | Earl Moon
| I'm very familiar with the great board space savings of BGA and all the "claims to fame." However, can someone out there tell me if any concern exist in the inspection realm. Additionally, solder cracking, CTE/TCE mismatches, no leads for stress re
Electronics Forum | Sun Dec 11 22:39:36 EST 2016 | ppcbs
We have been using the Amtech line for over 12 years now with all of our PCB and BGA Rework. The NWS-4400 is mildly active and will give better results with Lead Free Solder. Note that the LF-4300 is considered a No-Clean. However it will show lea
Electronics Forum | Mon May 28 07:30:52 EDT 2001 | bobwillis
Here is a draft visual inspection guide for underfill, please pass this on to the relevant people for any comments or suggestions. I am currently working on the pictures to go with the reference guide. Flip Chip/uBGA Underfill Visual Standards The
Electronics Forum | Tue Mar 01 15:13:22 EST 2011 | felixgutierrez
Hi Everyone. I would like your input in regards to lead free solder paste lead free. Which one is the most reliable solder for BGA's and BTC's (QFN). I have used different type of solder and on some of them i get big voids on BTC's and other one i g
Electronics Forum | Thu Sep 17 07:06:15 EDT 1998 | joakim fagerlund
We have problems with voids when we solder lids to ceramic flatpackages. The sealring of the package is gold(100 micro inches or 2.5 micro meters)with a underlayer of Nickel The solder is attached to the lid (preform) and the solder material is Au/S
Electronics Forum | Wed May 20 17:18:09 EDT 2009 | daxman
Just out of curiosity, how are you or anyone else determining a defect? Last I checked, IPC had no criteria yet for solder defects for QFN components. Has this changed? Biggest problems we see are voids which our x-ray shows a lot of. Our problems
Electronics Forum | Wed Mar 04 13:06:45 EST 2015 | cyber_wolf
A full blown analysis could become very expensive. There are many test that can be performed. 3D acoustic microscopy, X-ray, Dye and pry,and I'm sure the list goes on. Typically, a micro-cross section report of the BGA solder joints will show you w
Electronics Forum | Fri Nov 22 10:38:30 EST 2002 | slthomas
The follwing is from the Technet archives, per IPC's Jack Crawford. I dug it up during some investigation of a supplier's issues with humidity in an Asian plant: There is support for this in IPD-HDBK-001 w/Amendment 1 Handbook and Guide to Suppleme
