Electronics Forum | Fri Dec 20 15:38:53 EST 2013 | island2013
Aperature layout on your stencil could be a root cause as well. Home plate design aperatures have cleared this issue up for me in the past. If it's a clean product, running through the wash may get rid of quite a few of them. Also check your IPC s
Electronics Forum | Mon Aug 31 22:30:09 EDT 1998 | Kelly Morris
We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. Our pad design is .020" diameter pads with .025" solder resist diameter. The center
Electronics Forum | Tue Sep 01 19:16:51 EDT 1998 | Kallol Chakraborty
| We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | Our pad design is .020" diameter pads with .025" solder resist diameter. The ce
Electronics Forum | Tue Sep 01 02:50:40 EDT 1998 | karlin
| We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | Our pad design is .020" diameter pads with .025" solder resist diameter. The ce
Electronics Forum | Thu Nov 19 01:56:01 EST 2009 | lococost
Thanks dave, We have our problem down to the stencil (printer). We are unaware of any design rules concerning aperatures on glue stencils, does anyone know of any?
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 | Thu Sep 23 23:42:52 EDT 2004 | KEN
The LF pastes will have virtually NO wetting spread. This is normal. LF mobilities are virtually non-existant with SAC alloys. However, the addition of varrying amounts of silver can (and does) improve mobility but, this comes with a price (paste
Electronics Forum | Tue Feb 12 17:57:42 EST 2008 | chef
I must ask the silly question- are you sure you deposited the correct amount of paste? Depending on aperature design-the voiding could come from a stencil that has its holes partially built up with old paste. If paste volume is guaranteed, then what
Electronics Forum | Thu Oct 23 10:27:38 EDT 2014 | island2013
Is this happening on a new product you just introduced to the factory? If so, then I would check stencil design. Many moons ago we had a similar issue and discovered we were applying too much paste on the chip parts. We changed to a homeplate desig
Electronics Forum | Tue Sep 01 20:36:05 EDT 1998 | Rin Or
| We are experiencing shorting on a BGA. The part has a 1mm pitch with a 196 I/O count. The problem seems to pop up without warning & disappear in the same manner. | Our pad design is .020" diameter pads with .025" solder resist diameter. The ce
