Electronics Forum | Thu Feb 04 10:00:26 EST 1999 | Terry Burnette
| I'd like to find some technical papers on the reliability of reworked BGAs. If you know of any, please let me know. | | I have a concern about this because our current rework process does not apply solder paste to the pads prior to placing the pa
Electronics Forum | Tue Mar 13 11:50:21 EST 2001 | gsmguru
Here is some general things I usually ask myself when having trouble with BGA's What type of BGA ? Pitch/Bump Dia etc. Smaller bumps sizes & tighter pitches require more attention. This also impacts stencil aperature design & paste selection. Was
Electronics Forum | Fri Oct 08 17:03:03 EDT 1999 | Dave F
| Hi, | | Help! Could anyone help to enlighten me on this? | | Question: | | If I have a CSP/BGA package of size X by Y and the standoff gap between the component and PCB is Z, What is the maximum allowable Y/Z or X/Z that using a normal water cl
Electronics Forum | Wed Apr 27 10:47:26 EDT 2005 | HOSS
A 1:1 pad to ball diameter will cause the balls to collapse more giving you less post solder component standoff. Depending on the application of this product and required reliability, you may want to stay with the padstack being used. You may try c
Electronics Forum | Wed Feb 06 15:51:26 EST 2008 | jax
We have place CSP devices with 0.105mm standoff hights without any issue. The ability to Water Wash all depends on the specifications of your wash... Spray pressure and qty of jets Dwell time, pre-wash/wash/rinse Available detergents or saponifiers
Electronics Forum | Tue Dec 29 11:40:24 EST 1998 | Michael Allen
I don't have answers...just comments. We're just starting to assemble CSPs on protos, and I've got the same concerns you have. The MicroBGA package I'm working with has a ball diameter of 0.325mm (0.0128") and a standoff of just 0.010" BEFORE solde
Electronics Forum | Wed Dec 07 16:01:45 EST 2005 | JP
I am attempting to reball some PBGA's with no luck. The problem is getting the solder spheres to sit in the stencil apertures and removing excess spheres. I apply light amount of flux to pads of a BGA, align a stencil over a BGA, then pour solder s
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 13 21:52:16 EST 2003 | davef
Haaaaaa!!!! You contractors get all the fun don't ya??? Consider: * Replacing the balls on the corners of the devices with balls composed of a "hard solder", yano something like 90/10. * Shimming to prevent excessive collapse of a heavy BGA during
Electronics Forum | Tue May 21 17:16:51 EDT 2002 | davef
Larry, Yes, no matter how much you�d like to avoid using NC, you probably will have to start using the stuff, if the design [sales, in your case] types have their way. We can clean WS under 1mm and 1.25mm pitch BGA. For 0.8mm pitch BGA, we use NC.
