Electronics Forum | Mon Oct 13 19:04:47 EDT 2003 | davef
Aperture size should vary with the component [pitch]. That size should be the same a the pad size. So, generally pinching is not required. Indium discusses BGA apertures on their site [ http://www.indium.com ]
Electronics Forum | Thu Sep 12 10:45:29 EDT 2002 | pbarton
We have used a laser cut stencil 0.15mm (0.006") thick with 0.3mm (0.012") square apertures radiused in the corners 0.06mm (0.0025") to aid paste release. This approach with the (type 3) paste we use has proven successful on thousands of devices plac
Electronics Forum | Thu Oct 30 22:29:58 EDT 2008 | davef
For most applications, a nice square [or rectangle] pad works just fine. Assemblers ship boat loads of boards with these every day. It's reasonable for tight decoupling capacitor requirement applications to use round or radiused pads for components
Electronics Forum | Thu Oct 30 15:07:40 EDT 2008 | jemills
Hello I have a new 0402 pad design on a recent board were building in future. On closer look i thought the pad was a thru hole mount , but upon closer inspection the round pads are for 0402 comps. I had a discussion with the engineer and he said
Electronics Forum | Fri Oct 14 14:09:19 EDT 2005 | bschreiber
Your problem is not the 0.4 pitch. Your problem is the manual cleaning. Manual cleaning will only remove the solder paste from the surface of the stencil. What's more, manual cleaning will force additional contamination into the 0.4 pitch apertures
Electronics Forum | Fri Apr 11 01:52:26 EDT 2008 | andrzej
0,66 Is it ok ? Is it overprinted r - radius of stencil aperture - 9mils ~ 230um t - stencil thickness - 150um Other data : diameter of soldermas - 26mils Diameter of pad - 18mils Diameter of stencil apertre - 18mils Pitch - 0,8mm ~ 31mils What s
Electronics Forum | Fri Apr 11 06:22:04 EDT 2008 | andrzej
Hi Andrzej, > > We are using for BGA (0.8 pitch) > square apertures size 0.4 mm (rounded corners r = > t) and stencil thickness t=5 mils. So area > ration-_ w/4t=0.8 > > Regards Jan Hello Jan, I understand that you have the same pad dimensio
Electronics Forum | Fri Apr 11 05:51:20 EDT 2008 | janz
w/4t=0.8 Regards Jan
Electronics Forum | Wed Apr 16 02:46:55 EDT 2008 | andrzej
Thanks Jan for hints
Electronics Forum | Wed Feb 22 08:02:56 EST 2006 | dj44
I was looking for an stencil design for a 0.5mm pitch uBGA. Pad size is 0.38mm in diameter. We have been using 5mil stencil with type 3 no clean paste. What size aperture should we be using? Any suggestions?
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