Electronics Forum | Thu Sep 12 01:49:28 EDT 2002 | ck
Hi all, Any stencil opening recommendation for 20mils pitch mirco BGA. Currently, using 12mils round opening, 5 mils thickness. Seen to have weak joints as it crack after Ict testing. thks
Electronics Forum | Mon Dec 16 13:33:09 EST 2002 | pjc
square apertures provide better paste release than round in most applications. See IPC 7525 Stencil Design Guidelines
Electronics Forum | Wed Feb 05 14:20:45 EST 2003 | Stephen
One thing that worked for me was simply rounding off the pads, making square pads into circlesfor the stencil. It worked but did seem a little strange turning squares into circles for 0603's and 0402's and turning cirlces for BGA's into squares, (bu
Electronics Forum | Tue Feb 11 11:19:47 EST 2003 | dphilbrick
I agree with Dave, If you want to achieve S 20.20 you need the best. We were certified last year and due to the support we got from our vendor to guide us through what to do and not do as well as their ongoing training we passed first round.
Electronics Forum | Thu Mar 20 14:01:34 EST 2003 | MA/NY DDave
Hi I understand that more circular or rounded pads also reduce the effect. I love it when many independent variables can alter the outcome. YiEng, MA/NY DDave
Electronics Forum | Wed Nov 05 18:02:48 EST 2003 | gregcr
I also have used square apps on the BGA's, this also allows for a bit more play in alignment of the ball to pad, I am interested in the reasons why to use round apps on 0603's and 0402's ???
Electronics Forum | Mon Nov 24 19:21:04 EST 2003 | alwil
Hi, I have seen this problem. Make sure that the peeler tape goes round all three pulleys as in the diagram on the feeder. Make sure the feeder clutch is oil free and not slipping. If everything is set correctly then it may be a component vendor i
Electronics Forum | Fri May 21 15:49:50 EDT 2004 | M.L. Feather
I have never heard of using a corner of a trace before. How interesting. However, the Universal GSM only gives me the standard shapes of fiducials. (round, square, diamond, cross etc.) Thank you for replying. M.L. Feather
Electronics Forum | Fri Oct 15 10:38:42 EDT 2004 | mattkehoe
Thats what I was thinking especially because the pads are not round, they have jagged edges which to me indicates some kind of development issue. mk
Electronics Forum | Wed Oct 20 13:53:22 EDT 2004 | Greg D
Hi, What's the maximum and minimum solder void that can be accepted during X-ray? What about the percentage of Ball Roundness..20%? 30%? thanks and regards,
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