Electronics Forum | Tue Oct 28 17:40:58 EST 2003 | davef
We theorize a secondary [bottom] side BGA can be wave soldered with planning. Issues are: * Keepout between the BGA and one side of the board that is clear of PTH parts requiring wave soldering, so to support the fixture. * Keepout around the BGA. *
Electronics Forum | Mon Jan 14 22:52:48 EST 2008 | davef
Using larger pads on the corners is fairly common to improve self-alignment of BGA and CSP. For example, "9.3.2.8 Large corner pads and overprint The self-alignment of BGA or CSP can be improved through a design change. By utilizing a large board pad
Electronics Forum | Mon Oct 02 19:04:53 EDT 2006 | DC
We had a issue on the SBGA and found stress built up at the corner of the SBGA after cool down to room temperature. It is confirmed by the warpage analysis. I expected that the stress caused by the heat spreader and the epoxy to the copper frame. O
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 | Fri Oct 27 08:53:25 EDT 2006 | russ
I thjink you should bake these parts for 24 hours at 125C I used to have this problem and I even think it was the same package to be honest. Since we started baking all BGAs for rework process regardless of "condition of storage" we have increased
Electronics Forum | Tue May 01 20:39:41 EDT 2012 | davef
Good luck with that. A couple of things to think about ... * BGA self-align during reflow, just get 'em on the pads * Add a box [or four corner] legend on the bare board to help you position BGA
Electronics Forum | Wed Feb 10 08:37:31 EST 2016 | davef
bga hosed by physics ... to find some older threads on the topic BGA Bowing on the corners. - SMTnet [http://www.smtnet.com/Forums/index.cfm?fuseaction=view_thread&Thread_ID=6405 ] www.smtnet.com › Electronics Forum • Aug 22, 2003 - 5 posts - 1 au
Electronics Forum | Thu Sep 15 09:31:02 EDT 2016 | ladmo1
While removing one part, another part - BGA part - several components away, actually melted on one corner - you can see the plastic body of the part oozing out around one corner between the solder balls. Several of the solder balls on the one corner
Electronics Forum | Wed Nov 29 00:43:45 EST 2006 | callckq
Dear all, Recently, we run 2 models with heat sink attachment on top of this BGA(on top of this BGA, there is flip chip attached at the center of the BGA). Hence, the center of the BGA is higher than corner/side. We used conventional way to attach
Electronics Forum | Sat Aug 23 08:26:54 EDT 2003 | davef
In line with Russ' comment, look here: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=22497