Electronics Forum | Mon Feb 10 16:59:57 EST 2014 | hegemon
It is sort of a self answering question if you come in from the solder paste angle. First....start gathering data. Check every day, or every new paste jar, for: Storage conditions (temp), paste expiration date, ambient temp and humidity where yo
Electronics Forum | Thu Dec 24 03:49:45 EST 1998 | John Watt
| | | Folk's, | | | I'm in need of some help / direction. I'm working on my thesis for a masters based on looking at the effect's of the solder resist promoting / reducing the amount of solder ball's during wave. I'm looking at thing's like colour,
Electronics Forum | Wed Mar 21 16:32:03 EST 2001 | mparker
The root cause is dependant on the type of solder "splash", ball, whatever, that you are seeing post reflow. If it is smears, then cleaning the stencil underside is probably the answer. Are you using automatic wipers? How many print cycles between w
Electronics Forum | Thu Oct 26 17:42:29 EDT 2000 | Philip A. Reyes
Hi Mr Paul! Thanks for answering my previous questions. Hope you can still accommodate my other queries. This is about the acceptable criteria of PBGA defects after reflow soldering. 1.What is the allowable (min and max. ball misregistration / misal
Electronics Forum | Tue Jun 25 15:30:49 EDT 2002 | Steve L
Hi everyone. I am now faced with a problem on soldering PBGA. At first, I ran the board (FR4, 7" X 10" with 12 layer) at Peak Temp: 205 C and 54 seconds above 183 C. After reflow, I found several cold solder joints and one ball without second collaps
Electronics Forum | Mon Mar 30 16:02:44 EST 1998 | Michael Allen
| We have successfully put .016" vias in .030" pads. | There is no issue with .030" solder balls, since | the actual volume of the .002" via in pad is small | compared to the ball+solder paste volume. | We did notice random bubbles where, apparentl
Electronics Forum | Mon Jan 21 15:55:53 EST 2002 | Yannick
The point behind traces and vias on my test is that I don't only want to perform test on printing and placement but on reflow too, so a board with many components and no trace will not react like a board with traces on it. Unless you or someone else
Electronics Forum | Wed Apr 09 13:30:20 EDT 2003 | davef
In order to get reliable reflow, you need to be at or higher than [liquidus + 20*C] for about 5 to 10 seconds. [I said 25* in a earlier post, but in an effort to stay on message, I'll stick with 20*] Don't forget that your liquidous is probably NOT
Electronics Forum | Wed Jun 21 13:25:16 EDT 2006 | muse95
I see what you're saying - I'm not a process guru by any means. I was going on the premise that SAC melts at a higher temperature than SnPb. Basically I think of it as a BGA is joining solder to solder, unlike an SOIC where it is tinned metal lead t
Electronics Forum | Thu Apr 15 15:07:20 EDT 1999 | Mark Charlton
| | | Can someone explain the difference between solder "fines" and solder balls? Is there an official specification where "fines" are defined? What is the spec for "fines"? | | | | | | I consider "fines" individual unmelted metal spheres that ar
