Electronics Forum | Tue Sep 10 08:22:36 EDT 2002 | davef
I doubt that the interposer is FR4, it's more likely to be BT. Warp during reflow is a function of material a reflow recipe. Your ramp is too fast and is causing the interposer to bend like a potato chip.
Electronics Forum | Thu Jul 10 22:46:08 EDT 2008 | davef
We'd like to see pads on the board that closely resemble those on the interposer.
Electronics Forum | Mon Aug 11 09:21:04 EDT 2008 | davef
Sounds like solder is not taking to the pads of the BGA interposer. Check the solderability of the component.
Electronics Forum | Mon May 28 17:43:33 EDT 2001 | davef
Does this device have a integral heat sink / metal slug on top, like a TI TM320C6XXX er a Altera EP20K4XX? Compare the size of the pads on the interposer and the board. Compare the type solder mask [NSMD vs SMD] on the interposer and the board. Wh
Electronics Forum | Thu Feb 20 17:18:24 EST 2003 | davef
Give us infortmation, please. What is [are]: * Height board to board side of the interposer on the low side of uBGA * Height board to board side of the interposer on the high side of uBGA * Alloy of solder balls, no paste was used correct? * Type of
Electronics Forum | Tue Nov 13 19:58:28 EST 2001 | davef
No. I have never measured the temperature of the top of a BGA package during wave soldering. Mr. Kelly�s "actual body temperature" of 140-150�C during wave soldering is probably accurate [most of the time]. It�s the utility of this measurement tha
Electronics Forum | Tue Nov 18 15:03:39 EST 2003 | Mark
Yup. I'm attempting a small, but very important experiment. I need to solder several Lead-Free Globtop BGA parts to a Pin-Socket interposer assembly. I'm trying to come up with the best way to do this. I'm thinking of using lead-free solder paste, (b
Electronics Forum | Wed Nov 19 16:35:27 EST 2003 | davef
We'd be incluned to dip the BGA ball in tacky flux, place the BGA on the PTH interposer, reflow that suka, and get on with things. [Take the people involved out to lunch with the money you save on not buying a stencil.] On damaging the glop top, we'
Electronics Forum | Wed May 04 22:04:55 EDT 2005 | davef
First, you cannot determine if this is "black pad" by looking at it. You must do laboratory analysis, either microsectioning or EDS. [But it sure sounds like "black pad."] Second, if it is black pad, it was created by the company that fabricated t
Electronics Forum | Tue Jun 02 21:27:22 EDT 2009 | davef
We've never heard of a situtation where oversized pads caused voiding. Your supplier is correct that the pads on the board should be the same size as the pads on the interposer, but this is to improve reliability issues. Search the fine SMTnet Archi