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 | Tue Jan 14 11:53:44 EST 2020 | avillaro2020
Hi Phil, thanks. I am successful using the same connector on small thinner boards 2-2.5kg) i cant make it work, tried all kinds of profiles with vapour phase but to no avail. Yes you read it right 4.3-6.3mm pcb thickness and 2-2.5Kg. And it is 44 lay
Electronics Forum | Tue Feb 07 16:45:32 EST 2006 | Mike
Can someone point out what sort of defects at the joint I can expect if solder is above liquidus for 3-4 minutes rather than the typical 1 - 1.5 minutes. Voids? Grainy joints? Poor wetting? Thanks
Electronics Forum | Thu Apr 22 12:27:47 EDT 2004 | barry
I placed thermo's at 2 of the problem devices. Soak (time 150 to 180) 100 sec. Time above 180 =80 secs with 208 deg. peak. The solder appeared to flow at these pads, but little to no adhesion to the joint.Total time in oven was 5 min. All other joint
Electronics Forum | Fri Feb 21 19:49:36 EST 2003 | MA/NY DDave
Hi Good Luck Neil, When I first saw this process described, what you are experiencing was my first visual thoughts. Partial filling as well as huge solder voids inside of the joints. I figured for low reliability product or short life maybe this t
Electronics Forum | Thu Jun 16 22:33:54 EDT 2005 | davef
Peter: Please explain: * You say, "The cooling phase is important to perform the strength of the solder joint." [We agree that fast cooling rates produce fine grain in solder and that fine grained solder connections are stronger than coarse grained.
Electronics Forum | Fri Apr 03 03:41:04 EST 1998 | Frank J. de Klein
150 secs. On bilayer boards (Cu only at top and bottom) you can typically not reach differences top to bottom bigger then 35-40 C. For multilayers however, the maximum is 15-20 C. If you actively cool a multi- layer at the bottom during the 2nd pass,
Electronics Forum | Thu Apr 15 16:07:37 EDT 2004 | barry
Hi there all, we are having problems with 2 qfp devices. grainy poorly reflowed solder joints. One 100 pin .5mm pitch, and one 64 pin .5 mm pitch . Both of these devices have a thermo pad on the back of them (pad area soldered to back of device)which
Electronics Forum | Wed Aug 09 07:32:11 EDT 2006 | mumtaz
The curled legs may push the paste out of the hole, making things messy. This also will decrease your volume of paste which means your solder joints are not as robust as you would like. Also with this process, voiding can be a big issue depending o
Electronics Forum | Thu Jun 22 12:25:07 EDT 2000 | Boca
Jason, What Chrys said! Don't try to run the bottom cooler, tried it in the mid 80's, don't work and don't want it to work. If one side of a fab is maintained cooler than liquidus and the other side into reflow it would have an easy 40C temp diffe
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