Electronics Forum | Wed Jul 03 15:58:16 EDT 2002 | davef
Your thinking is correct. Wave soldering pads that were designed for reflow can create problems: * Large pads used for reflow [too much solder] can create reliability problems. * Bridging [too much solder] creates rework. * Skipping & shadowing from
Electronics Forum | Wed May 09 01:23:17 EDT 2001 | GregH
Hi, My Bottomside component pads are 1:1 with my topside land sizes/dimensions. I have difficulties catching solders on my bottomside smd chips (SMB Diodes, 0805 RC Chips). What should the bottomside components for wave soldering be greater than my t
Electronics Forum | Fri Jan 14 11:16:45 EST 2005 | Dan Gosselin
I have heard of people using a round pad or Home plate design to decrease the incidence of tombstoning on 0402's Anyone have any practical experience on this or is everyone just using the IPC 782 recommended land pattern (28mil x 33mil rectangle pad
Electronics Forum | Thu Jun 04 20:06:30 EDT 2009 | davef
Since posting the above comment extolling the virtues of NSMD pads and disparaging SMD pads, we've learned that the points apply to all array devices, but in spite of that some designers of fine pitch [eg, 0.4, 0.5mm pitch] array devices choose SMD w
Electronics Forum | Wed May 09 10:40:10 EDT 2001 | davef
First, your primary side component pads should be designed according to SM-782A, "Surface Mount design & Land Pattern Standard". Next if you did that and your secondary side component pads are the same size as your primary side components, your diff
Electronics Forum | Fri Jan 14 14:59:52 EST 2005 | russ
We use a 25 x 25 mil square pad with a 18-20mil GAP with great success. Russ
Electronics Forum | Mon May 25 08:37:28 EDT 2009 | d0min0
Hello, recently we changed supplier of the LF BGA, we did corossection and now have doubts... previous BGA specs : pitch 1mm, ball diameter 0.6mm future BGA specs : pitch 1mm, ball diameter 0.4mm on the crossecrion we found that one of the ball seem
Electronics Forum | Mon Jan 17 17:56:14 EST 2005 | russ
Haven't noticed any major difference between C's and R's. Our biggest problem is feeders that will advance to the same location and leave the part in the pocket. We see "billboarding" on R's when the feeder isn't working right. If you have a good
Electronics Forum | Mon Nov 01 10:29:13 EDT 2010 | scottp
I've searched the archives and maybe my search skills aren't up to snuff but I couldn't find much. I'm curious what people are doing for 0.4 mm pitch BGAs, assuming a type 4 paste. Pad diameter? SMD or NSMD? Stencil thickness? Aperture diameter? Us
Electronics Forum | Wed Oct 11 13:40:20 EDT 2023 | proceng1
Agreed. Your "leads" are fairly small compared to the PAD area, so you leave your part lots of room to "stretch it's legs". One thing that I have trouble communicating to my operators is that placement does not have to be perfect, and neither does t
