Electronics Forum | Mon Dec 09 21:15:27 EST 2002 | MA/NY DDave
Hi I haven't looked yet at what DaveF gave you. It is my guess that your SJR stands for Solder Joint Reliability. The answer would in general be NO to your question. Usually things in the design community are done in steps that provide a certain
Electronics Forum | Thu Nov 08 10:26:12 EST 2007 | slthomas
"1/2 of the paste volume is lost from the flux and carriers being removed during the reflow." Don't forget the intersticial space between your solder spheres that you lose during reflow. Not being of an engineering background I couldn't begin to a
Electronics Forum | Thu Dec 05 17:40:24 EST 2002 | davef
While unfamiliar with some of the terms you use, could this be what you seek? http://www.pcbstandards.com/downloads/Metric%20Environment/General%20Documentation/PCB%20Design/PCB%20Design%20Routing/Metric%20BGA%20Routing.pdf Stepping backwards just
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 | Thu Jul 23 11:39:16 EDT 1998 | Russ Miculich
Are you using a HASL board or an organic protection on the pads? This will help determine as to whether paste is necessary or just a very active/tacky flux should be used. Tight process control will also help in the reflow oven. Many users don't wan
Electronics Forum | Thu Nov 07 15:06:11 EST 2013 | hegemon
1st X-Ray looks pretty good. One instance of what looks like solder migration in the lower left quadrant. 2nd X-Ray shows a number of locations where the solder has migrated into the vias, shown by the small dark circles between the main spheres.
Electronics Forum | Mon Feb 12 11:13:12 EST 2007 | davef
Q1. If I go to the Pb-free solder paste, is it necessary that I have to change my reflow oven OR just by changing with respect to solder paste specification, I can reach my goal? A1. It depends on your current oven. Some ovens can meet the higher t
Electronics Forum | Thu Oct 14 12:12:21 EDT 2004 | Shean Dalton
Hello JB, Based on the double sided assemblies, the misprint cleaning process can demand the cleaning system to remove both raw solder paste from the misprinted side of the board, and, reflowed flux residues from the assembled side. Recognizing and
Electronics Forum | Mon Mar 29 11:48:43 EDT 2010 | davef
SAC BGA In A Sn/Pb Reflow Process Conclusion: Area array components (ball grid arrays, chip scale packages, flip chip packages) with Pbfree solder sphere alloys should not be reflowed using a tin/lead reflow profile due to the resulting non-uniform s
Electronics Forum | Tue Apr 10 13:43:13 EDT 2001 | mparker
since you did not define what visual process you are inspecting with I will ask is this "grainy" appearance being detected with the naked eye only? Are you using magnification? if so, what power? Is this a SMT solder or through hole solder problem?
