Electronics Forum | Wed May 15 08:33:43 EDT 2013 | emeto
SAC is a lead free alloy that comes from SnAgCu(tin, silver, copper). When you say SAC305 that means 3%Ag 0.5%Cu and the rest is Tin. About the LF I assume that it means Lead Free, but what metal contents it has I can only guess.
Electronics Forum | Thu Jun 27 08:41:38 EDT 2013 | emeto
I would suggest that you go to the X-Ray world. I know for sure that Dage(Nordson Company) can make actual u-cut for the ball of the part. They can see and measure everything in 3D. I am sure if they can do it other X-ray machines can probably do it
Electronics Forum | Fri Dec 20 06:12:17 EST 2013 | bandjwet
Jimmy: Make sure to look in and around the board to make sure you have captured all locations of solder balls/fines as they are commonly caused by the profile or print issues. If they are non-embedded and are a 610 defect based on the class of your
Electronics Forum | Mon Feb 10 14:34:56 EST 2014 | jigo91
Hi, I wanted to know how can we test our paste quality, as viscosity, temperature in which it is delivered to the SMT line and other variables that can affect our paste dispense or soldering. Our concerns are that paste quality may be causing solde
Electronics Forum | Fri May 23 15:33:39 EDT 2014 | hegemon
I don't see any visuals that make me think of black pad phenomena. I do note that it appears that pads on the BGA itself have detached and been left on top of some of the solder balls. To me it looks like the temperature profile is not correct, not
Electronics Forum | Thu Jun 12 11:49:56 EDT 2014 | patel_daxa29
No, is will not create random solder balls. I have experience doing this(When we had a big via in middle of filter cap which was sucking all solder ,leaving insufficient solder for a joint).I calculated volume of via hole to determine the expansion o
Electronics Forum | Fri Mar 27 13:08:14 EDT 2015 | ppcbs
We reflow solder balls to the LGA using a tacky paste flux. Then we install the LGA to the PCB using a tacky paste flux. This will result in zero voiding and is a preferred method of our Military and Space clients. Be sure to read your spec sheet
Electronics Forum | Wed Jul 06 06:17:11 EDT 2016 | pavel_murtishev
Dear members, Recently we have found that solder mask thickness variation could lead to solder balling under QFN packages for a high reliability device. Is there any industry proven method for solder mask thickness checking? Any equipment or any me
Electronics Forum | Mon Sep 19 21:35:54 EDT 2016 | shriram
Appreciate your suggestion. NSMD pads are used for this design, the anomalies we found are 1. the trace running between pads has a lesser solder mask height compared the other area of the pads. 2. the NSMD pads doesnot have a trench close to pad e
Electronics Forum | Fri Sep 30 10:37:35 EDT 2016 | ttheis
We sometimes have a misprint and we would never re-print on a board with paste on it already because it will surely get paste all over the bottom of your stencil and could smear between traces. If we do mispront we have to clean the paste off the boa
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