Electronics Forum | Tue Oct 05 12:42:43 EDT 1999 | Chris May
| I am a new employee at a company that has had a large turnover of employees over the past year. I am working on a board (components on one side only), the engineer (he is also new ) wants to use an .035 pad with a .021 dia. hole, there are no via's
Electronics Forum | Fri Feb 07 15:17:14 EST 2003 | MA/NY DDave
Hi I am pretty sure it isn't the pad that is causing the problem. To me it seems like those via holes through the pcb either to an internal plane or to the other side. I can imagine creating an interesting stencil to accomodate the vias yet you are
Electronics Forum | Sun Jan 09 19:37:15 EST 2005 | Bob R.
I'm just thinking out loud here with no experience to back it up, but I could see where you're trapping air or solvent filled voids inside the via by tenting from both sides. When you go through a heat cycle like reflow or wave solder you could be e
Electronics Forum | Thu Jul 08 12:33:52 EDT 1999 | Mike Demos
Thank you all for your replies. Thanks to your replies and backup from the IPC-SM-782A (section 3.6.3.2) and James Blankenhorn's "SMT Design Rules & Standards," the designer has agreed to provide adequate clearance between the via and the pad. I wi
Electronics Forum | Thu Aug 25 10:17:48 EDT 2005 | davef
Send the pic to dave5252 at hotmail.com [you can't send pic through the SMTnet email thing] For more on via plugging, tenting, capping ... look here: http://www.merix.com/technology.php?section=processes&page=pdf/Via_Fill_Plug.pdf Something, a voi
Electronics Forum | Wed Jul 20 15:05:28 EDT 2005 | Fred M.
With the new rev D release of IPC-A_610 came a new section 10.2.9.3 which identifies a via (through hole) with nicks along the inside of the annular ring. Defect is all three classes and states "Damage to conductor or lands". We have for years defa
Electronics Forum | Sat Jan 22 20:59:51 EST 2000 | Jeff Sanchez
Michael, I am not sure if you are trying to lay out a board with vias in the pads or suffer through an assembly you got stuck with? I am building run of boards right now that has vias in most the smt pads. I'm sure the design group thought it was
Electronics Forum | Tue Sep 25 14:08:59 EDT 2001 | davef
Oooo, the solder on the pad and PGA ball is flowing during reflow down the via to the secondary side? Why didn�t you say so?? ;-) Why would you expect that gravity and capillary action wouldn�t force solder to flow down the solder plated via to the
Electronics Forum | Thu Oct 01 11:40:17 EDT 1998 | Justin Medernach
Are there anyone who can give me the answer about solder ball problem? | We have 12 layer PCB and double sided PCB. After one side reflow soldering We found lots of solder ball under the PCB. The solder ball was coming out from via hole. | So
Electronics Forum | Wed Oct 06 04:23:09 EDT 1999 | Brian
| | I am a new employee at a company that has had a large turnover of employees over the past year. I am working on a board (components on one side only), the engineer (he is also new ) wants to use an .035 pad with a .021 dia. hole, there are no via
.gif)
