Electronics Forum | Wed Mar 03 11:30:18 EST 1999 | dave reese
Are square pads more difficult to wavesolder than round pads? I am referring to a through hole board.
Electronics Forum | Thu Mar 04 12:49:49 EST 1999 | SMTASSY
| Are square pads more difficult to wavesolder than round pads? | I am referring to a through hole board. | Usualy square pads are for indication of pin 1 on a DIP for example. There might be a difference in the capilary affect due to a different su
Electronics Forum | Wed Apr 28 04:26:24 EDT 1999 | Nigel Burtt
| Hello all, | | I read about Steve's headache a few articles back and I'm really interested by his tip. However, I'm still wondering why square apertures release solder paste better than round ones. For the same volume of paste, the surface area
Electronics Forum | Tue Jul 13 00:40:44 EDT 2004 | Darren
Yes of course we are doing placement of BGA's with an IPII. However there is no front lighting so you can not inspect the balls. If the silhouette is square enough there is no problem with alignment. Just use the largest nozzle that will fit on the p
Electronics Forum | Thu Sep 12 10:45:29 EDT 2002 | pbarton
We have used a laser cut stencil 0.15mm (0.006") thick with 0.3mm (0.012") square apertures radiused in the corners 0.06mm (0.0025") to aid paste release. This approach with the (type 3) paste we use has proven successful on thousands of devices plac
Electronics Forum | Wed Mar 17 14:59:53 EST 2004 | Claude_Couture
since there is a bit of humor in this thread, try drilling the pads from the opposite side of the pcb.
Electronics Forum | Mon Oct 13 19:04:47 EDT 2003 | davef
Aperture size should vary with the component [pitch]. That size should be the same a the pad size. So, generally pinching is not required. Indium discusses BGA apertures on their site [ http://www.indium.com ]
Electronics Forum | Fri Mar 19 10:06:22 EDT 2010 | karlo
Rework is typically done by heating the BGA to 170-180C to first scrape off the fillet. Then, heat to above reflow, and lift the BGA. Then, collapse the solder with heat and flux. Then, back down at 170-180C, scrape off the underfill from the boar
Electronics Forum | Tue Feb 17 04:52:13 EST 2004 | John W
There's normally a number of reasons people want to know what melts 1st, 1 - to see if you know, 2 voiding issues - whole can of worms 3 device alignment. One of our collegues has said that most balls are Eutectic, that's in fact not totally correct.
Electronics Forum | Fri Aug 22 00:20:29 EDT 2008 | rameshr
Hai, In our process we are using the micro bga of size 13X13mm of pitch 0.45mm,after soldering process the bga found collapsed, we absorbed that the PCB land pattern of the BGA was not in array, uneven distribution of pads (area) & most of the pads
