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 | Sat Aug 21 02:16:42 EDT 2010 | isd_jwendell
I do not have a QSP-2, but build boards where others have done the layout. Some have not included fiducials, and I am left finding other things. Some boards have complete tenting over the vias, so not all PTH pads will work. Drill holes are not as ac
Electronics Forum | Tue Sep 22 09:07:02 EDT 1998 | Steve Gregory
Hi Jacqueline! Do these joints that you're having problems with happen to be on fine pitch solder joints? Are the fillets staying attached to the foot and separating from the pads cleanly? If that is true, are there many vias concentrated aroun
Electronics Forum | Mon Dec 13 00:48:33 EST 1999 | armin
Hi All I have a 0.7 mm diameter hole for vias, what�s the minimum annular ring for this hole diameter? What�s the term unsupported and supported holes refer to in IPC-2221 9.1.2 Annular Ring Requirements? I have a proto-type PCB (designed by our R&
Electronics Forum | Mon Feb 19 22:56:20 EST 2007 | davef
Russ We agree with your comments on plugging from one side only. But... We believe that it IS possible to trap process chemicals [technically, not flux] in a blind [or any other] via. This can be done by plating the via closed, rather than pluggi
Electronics Forum | Thu Jun 04 08:32:21 EDT 1998 | Dave F
| | Hello: | | BACKGROUD: SMT components soldered on the top-side of boards that also require wave soldering have the potential to reflow during wave soldering. Reflowing these components during wave soldering is not good. It can cause cold joints
Electronics Forum | Thu Nov 25 21:43:49 EST 1999 | cklau
Via is normally a plated thru holes in (0.63 to 1.0 mm (0.025" to 0.040") diameter lands , which unless properly treated they must be located away from the component lands to prevent the solder migration off the component land during reflow soldering
Electronics Forum | Wed Jun 03 21:25:33 EDT 1998 | John Allan
| Hello: | BACKGROUD: SMT components soldered on the top-side of boards that also require wave soldering have the potential to reflow during wave soldering. Reflowing these components during wave soldering is not good. It can cause cold joints, op
Electronics Forum | Thu Oct 01 19:07:48 EDT 1998 | Paul R. Smith
Kyung Sam, Justin is correct, there is definately either a board design problem or the PCB maker issue. Obviously there are many mixed technology boards built in the world so I would lean towards a design issue as the root cause. Should you or you
Electronics Forum | Tue Sep 22 09:59:15 EDT 1998 | Mike C
| Hi Jacqueline! | Do these joints that you're having problems with happen to be on fine pitch solder joints? Are the fillets staying attached to the foot and separating from the pads cleanly? | If that is true, are there many vias concentrated