Electronics Forum | Mon Feb 03 18:37:28 EST 2003 | jonfox
Not to be off-topic, but push engineering for embedded passives and remove parts from the underside all together. Watch the material cost sky rocket, but watch the manufacturing cost sink and well as improve the production cycle by 50%. Sorry, I w
Electronics Forum | Wed Jun 03 13:50:32 EDT 1998 | Chrys
| Can anyone tell me if there is a reference for smt component height specs on the bottom side of a board, which will also go through wave soldering. A current design I am reviewing has tant caps(7343) and a crystal on the back side. Should I only b
Electronics Forum | Sat Nov 06 14:58:45 EST 1999 | Gary Moravchik
Assuming you are using Sn63/Pb37 solder paste, have you tried using a lower temp melting point solder paste for the second pass? For example, use 63/37 for first pass and a Bi58 compound solder paste for the second pass. If I recall, Bi58's melting
Electronics Forum | Fri Apr 12 16:30:21 EDT 2002 | stepheno
If you are going to wavesolder the board after SMT you will have to epoxy the parts on instead of paste/reflow. I used to work for a company that squeeged it on. You will have to research component layout guidelines if you do want to wavesolder. If
Electronics Forum | Thu Aug 25 10:32:03 EDT 2005 | davef
IPC-2221A, Generic Standard on Printed Board Design, the base document that covers all generic requirements for printed board design, regardless of materials. From there, the designer can choose the appropriate sectional standard for a specific techn
Electronics Forum | Thu Aug 13 12:23:39 EDT 2009 | robhs
Thanks Dave. What you say makes complete sense. We ran a job a short while back in this way (though without bonding) and found we had a much higher than normal failure of the BGAs which I can only attribute to the secondary reflow. As I have only got
Electronics Forum | Fri Apr 03 03:41:04 EST 1998 | Frank J. de Klein
150 secs. On bilayer boards (Cu only at top and bottom) you can typically not reach differences top to bottom bigger then 35-40 C. For multilayers however, the maximum is 15-20 C. If you actively cool a multi- layer at the bottom during the 2nd pass,
Electronics Forum | Tue Feb 04 18:46:01 EST 2003 | slthomas
"Use the pad mating to lead wetting area." If I get your drift, we're talking about the minimum lead area (assuming the pad has an area that's at least as large as the lead) required to be wetted by IPC-610. Hmmmm...that would take some calculation
Electronics Forum | Wed Apr 13 16:57:49 EDT 2005 | bradlanger
My company is just starting to do double sided smt. What options are available for under board support for printing and placing the second side? We are using a Dek 248 printer and Samsung CP Series placement machines.
Electronics Forum | Wed Sep 15 06:14:16 EDT 1999 | Wayne S.
| I'm looking for some good articles on reflowing of double sided SMT boards. I'd like to come up with a process for low volume prototyping, but need to understand the do's and don'ts. | Hello, you can get some insight by typing in double sided boa
