Electronics Forum | Wed Aug 15 13:40:55 EDT 2001 | rkevin
Just as there are a number of causes of solder balling there are also several factors which can lead to or encourage the formation of solder beads. - During the placement of the component solder paste may be squeezed out from underneath the compone
Electronics Forum | Wed Sep 05 08:50:04 EDT 2001 | davef
No arument with others comments about moisture, but taking a different tact, consider that the volitle elements of the solder paste disppear as a function of the amount of time the paste is out of the container. [Maybe as a function of solder paste
Electronics Forum | Mon Nov 05 20:34:03 EST 2001 | davef
What�s the problem? There area many heat related failure mechanisms in bare boards. You can damage boards with heat several ways. A couple favorites [Don�t try this at home. Perform on a closed track by professional solders only.] are: * Put a
Electronics Forum | Wed Nov 07 17:11:14 EST 2001 | davef
1 CAN WAVE SOLDER AFFECT OR DAMAGE BGA? Sure. Since you are vague, assuming: * Partially assembled board was not stored to prevent moisture absorption. * BGA is in a plastic package. * Partially assembled board was stored long enough to exceed th
Electronics Forum | Wed Nov 07 17:13:51 EST 2001 | fmonette
Hany, The guidelines for proper handling and storage of moisture sensitive components, like PBGAs are clearly documented in the joint IPC/JEDEC standard J-STD-033 (free download at http://www.jedec.org). In short you need to keep track of exposur
Electronics Forum | Mon May 27 12:14:35 EDT 2002 | arcandspark
I use the exact same paste flux that we use in our solder paste for SMT manufacturing with great success. I have also had great success using the Air Vac DRS Hot Gas units with the same size BGA's. If to much heat is applied to fast to the BGA be it
Electronics Forum | Fri Jun 14 09:15:02 EDT 2002 | edahi
DaveF, Yeah you got that right...because the initial stages of the project, the products would only attach 1 passive (capacitor) hell when things got too cheesy they wanted to attach 20 caps or so....this is not like board assembly, this only 1 Flip
Electronics Forum | Fri Aug 16 10:00:03 EDT 2002 | davef
You have a very bad situation. It�s tough for the gas, flux material, er whatever to escape when the BGA is sitting on top of it and the blind via is blocking it from the other side. Obviously the vias should have been: * Placed on the edge of the
Electronics Forum | Thu Sep 26 11:44:23 EDT 2002 | abelardo
Hello everyone out there in the SMT world. I have a dilema I'm currently running a board that has 3 csp's with a .75 mm. ball pitch and .3mm ball size. And 2 qfp's-160. The stencil is 4 mils thick and I'm using a 63/37 solder paste. My reflow prof
Electronics Forum | Wed Oct 23 16:56:03 EDT 2002 | mikestringer
Hi Marc I too have been using a fully synthetic Motor oil on Heller reflow ovens for a number of years. In our case Mobil 1 5W-50. We have a field failure problem with some 1% resistors under conformal coating where sulphates are dissolving the si
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