Electronics Forum | Tue Jan 31 12:02:22 EST 2006 | aj
how would you apply both pastes.? anyway, I have succesfully run leadfree bga with lead paste. You gotta find a profile that kinda meets both requirements. Taking into consideration the peak temp and time above. dont have details on hand but I ca
Electronics Forum | Wed Feb 26 21:44:52 EST 2003 | Paul Dansereau
I will be building a board, about 8 X 12 , .062" thick using a standard FR406 stackup. It has a variety of devices, including CCBGA , CBGA and PBGA's. Given the challenge of developing a reflow profile that will accomodate both ceramic and plastic BG
Electronics Forum | Mon Apr 09 02:57:16 EDT 2018 | robl
Hi, these are both power pins, usually connected to a dedicated inner VDD/VDDQ 1oz copper layer, making a very effective heatsink. I am guessing that not enough heat got to the ball to fully melt it, creating a weaker column rather than a beautifull
Electronics Forum | Mon May 16 22:59:40 EDT 2005 | davef
We believe your problem is caused by the mismatch in CTE of the material ised in your BGA. In fact, this "potato chipping" [where the corners curl-up] is present in all BGA. The issue is the matter of degree. [Mismatching CTE is how old thermostats
Electronics Forum | Fri Oct 22 06:19:42 EDT 1999 | TNT
Ron, if I am reading this correctly the 20mil parts are not having problems on a 6mil stencil. If you increase the entire thickness of the stencil to 8mils, there should not be any issues with the 20mil components. The supports you are using could p
Electronics Forum | Wed Jul 07 13:41:42 EDT 1999 | Dave F
snip | | If you go for plugging be sure you have a protrusion spec that you can live with. This often results in little bumps of epoxy that can interfere with component placement. For us, tenting .015 vias usually gets us about 80% coverage from
Electronics Forum | Tue Jan 31 12:13:26 EST 2006 | Calvin Kolokoy
Today's regular Sn-Pb paste chemistries are designed to run at higher peak temperatures ensuring that your lead-free alloys will coalesce with your regular Sn-Pb solder. That being said, it is do-able to solder both types in one oven. Generally, wit
Electronics Forum | Tue Sep 07 09:11:33 EDT 1999 | Dave F
| We've noticed that there are many different recommendations for pad sizes for various SMT parts. This seems to vary wildly from manufacturer to manufacturer for the same case sizes. Is there any standards that can used used to specify these sizes
Electronics Forum | Thu Nov 17 21:46:48 EST 2005 | C. Kolokoy
With DIP type components, a sub-par fluxing method (foaming a no-clean), and a chip wave where one is not needed are formulas for bridging and insufficient wetting. If you have SMD's on the wave solder side of the board greater than 0603, and no SOT
Electronics Forum | Wed Mar 10 13:53:13 EST 1999 | Vincent Vega
| We will wave solder a board with SOIC14 and SOIC16 parts on the bottom. It has been difficult to find any specific wave solder process recommendations from manufacturers of the SOICs. The pad geometry utilizes theiving pads on both sides to reduce