Electronics Forum | Sat Apr 17 17:08:22 EDT 2004 | finepitch
Russ has a hint by saying "too long of a soak at too high of a temp or being in reflow for too long/hot". I think the board should stay in the oven for 3-4 minutes, spending 60-90 seconds of which during reflow. in order to stay in the oven for 3 m
Electronics Forum | Mon Jul 19 21:25:28 EDT 2004 | davef
It seems like the flux is burning-up before the metal begins to flow on this slightly odd component. Alpha talks about alternate reflow recipes for WS609, as follows: * A straight ramp up profile is preferred for reflowing low to medium thermal mass
Electronics Forum | Tue Aug 17 03:26:57 EDT 2004 | soease
Well, regarding the paste specifications, it's no problem to add yours if it's not allready defined in the default library; parameters are for example, soak temp min & max, liquidous, ramp positive max, spike ramp min & max, all timings and so on. n
Electronics Forum | Mon Jan 10 16:14:17 EST 2005 | fmonette
Hi Gary, With plastic BGAs it is more difficult to remove the trapped moisture because of ground planes in the substrate. If your parts have been sitting around for a long time they may be soaked with moisture and in some cases the 48 hours bake cy
Electronics Forum | Wed Mar 02 05:14:07 EST 2005 | ABHI
Guys, Solder paste height worries all of us as we encounter the non wets after reflow. More so in fine pitch QFP's. The non wets are not always caused by solder paste height. Many other contributors. Even the pad geometry on te board can contribute t
Electronics Forum | Sat Apr 30 13:56:31 EDT 2005 | steve
My experience with different size boards and pre-heaters. The perfect world (right?) you would saturate the complete pcb with bottom pre-heat. But it is difficult with repair and rework equipment, not to mention the expense and foot print of large pr
Electronics Forum | Wed Jul 27 17:01:14 EDT 2005 | Dreamsniper
Issue: At 60'C test PCB Fails. Operator did simulation. Use of Heat Gun to heat up the BGA to 60'C while PCB is powered and running. At 60'C BGA fails. When pressed system is back which means that something becomes open. Sent BGA for SEM and found t
Electronics Forum | Fri Feb 10 12:09:53 EST 2006 | cyber_wolf
Russ, We use a unit called a Datapaq surveyor to monitor our ovens. Its basically a unit that a data logger rides through the oven in. It has 3 thermal couples across the top and 3 across the bottom. It takes measurements the full width of the proces
Electronics Forum | Wed Aug 16 13:52:24 EDT 2006 | russ
Oven settings are meaningless here. What does the board see? It is the paste we are concerned about not what the heaters are running at hehe. These solder balls are at the end of pad, which end? under the part or away from the part. I believe you
Electronics Forum | Thu Dec 21 21:37:19 EST 2006 | Jack
Hi Pavel, Real Chunks, Thanks for your valuable inputs..Selecting the correct location for board profiling is critical in determining the solder joint quality. Am I right to say TC wire attachment locations priority should be as below: (1) Thermal