Electronics Forum | Tue Jan 31 14:23:39 EST 2006 | samir
Chunks, For our lead-free eval, we had the same problem with "charred looking" solder paste up the component termination of one of the smaller discretes, coupled with excessive solder balling...this smaller part did see peak temps in the 240 range -
Electronics Forum | Thu Mar 16 10:41:34 EST 2000 | Russ
Are we talking midship SMT or wave soldering? SMT - I have found the best method is not having them (WOW) this can be accomplished through pad design, aperture design, placement accuracy, and profiling, It is my understanding however, that these
Electronics Forum | Fri Oct 06 09:38:11 EDT 2006 | C.K. the Flip
Here's the BGA voids-reduction profile that I used: http://img323.imageshack.us/my.php?image=profileka0.jpg Keep in mind, this was for Sn/Pb BGA with Sn/Pb solder paste. For your situation, you might want to raise the peak temperatures to at least
Electronics Forum | Thu Oct 05 11:48:00 EDT 2006 | Mario Scalzo, SMT CPE
Good morning all. We are able to offer some insight into the problem and offer a recommended reflow profile to solve this issue, but it really depends on the solder paste that you use, as different manufacturers use different boiling point solvents.
Electronics Forum | Wed Oct 04 15:06:57 EDT 2006 | C.K. the Flip
Hmmm.. you are in a pickle then. I have AIM's "Reflow Profile Supplement" where they recommend a Low-Long-Soak (LSS) profile for situations like your's. It's an old-school type profiling approach where you ramp up to 120*C for about 1 min. then soa
Electronics Forum | Wed Apr 11 22:05:58 EDT 2001 | davef
OA pastes are more hydroscopic than NC pastes. Hydroscopic. The capacity of a material to absorb and retain moisture from the ambient air. Sometimes this is compounded if you remove paste from the frig and let it warm to room temperature, because
Electronics Forum | Tue Jun 01 17:37:34 EDT 2004 | lynnmc
Any view on what the minimum reflow temperature is for a SAC ball bga to form a reliable joint with PbSn solder?
Electronics Forum | Tue Jun 01 19:25:19 EDT 2004 | Ken
...oops part 2: I will assume a sac 350 ball??? 217-218C this will completely reflow the ball and form a "normalized" joint with a collapsed structure.
Electronics Forum | Wed Jun 02 05:40:35 EDT 2004 | johnwnz
Is there not an issue with reflowign the SAC ball's in term's of drivign up the lead contect in a lead free joint that increases the risk of failure in them? certainly dramatically increases voiding... have some pictures of soem that a customer tried
Electronics Forum | Tue Jan 06 16:31:41 EST 2015 | jacklucas
In switching to lead free processing, we find ourselves having over 400 PCB part numbers with Sn63 HASL finish. And there is no hope of quickly purging inventory and getting our drawings changed to call out a lead free finish. I want to avoid having
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