Electronics Forum | Fri Nov 25 09:31:56 EST 2005 | davef
pyramus, First, search the fine SMTnet Archives for previous discussions on BGA shorts. Second, we're still not clear on the issue. * Is the problem with a BGA? If so, please describe the BGA, including any heat spreader * Is the problem with a uB
Electronics Forum | Thu Feb 23 08:06:03 EST 2006 | davef
"The three dispensing pumps used for encapsulation are the air/time syringe, rotary positive displacement pump (RPDP) and the linear piston pump. Each of these methods of dispensing offer different attributes but the most accurate method is the linea
Electronics Forum | Thu Mar 02 23:21:59 EST 2006 | KEN
I recently finished analysis of no-clean fluxes and Ionic contamination and cleaning processes. The results were eye opening. Summary: If you clean a no-clean you better do a good job. Many no-cleans produce a "waxy binder" to encapsulate the tro
Electronics Forum | Fri Jan 26 13:26:30 EST 2007 | rw
We are developing a new product that requires conformal coating on the motor controller. We selected a silicone based conformal coat due to its ease of use. There has been disagreement among engineers as to its impact on the motor. We have contact
Electronics Forum | Fri Apr 06 08:45:48 EDT 2007 | davef
UNDERFILL The design of the component and the end-use environment drive the requirement fot underfill. Here is a good introduction: http://www.asymtek.com/news/articles/2002_globaltronics_csp_and_fcuf.pdf Google for more. We have no relationship, n
Electronics Forum | Sat Feb 27 01:16:16 EST 2010 | jmelson
I had a batch of Xilinx chips that I believe had microscopic hairs of the lead frame left as slivers on the leads. These maybe got encapsulated by the solder plating, and then were free to move when the chips were reflowed. You could see the tiny h
Electronics Forum | Sun Apr 04 00:51:01 EDT 2010 | jmelson
On the Xilinx chips, I am pretty sure these hairs are NOT tin whiskers. The solder in this particular build was SnPb, and pure tin would almost certainly melt at soldering iron temperatures. My theory is that slivers of the lead frame material, lik
Electronics Forum | Thu Mar 24 11:04:41 EDT 2011 | smt_guy
Hi, I have a 2.75" x 1" x 0.027"thick CCA with SOIC16W and QFN56 as well as some 0201's, 0402's and QFN16 Components that are to be enclosed via molding process. Is there any Insert Moling, Over Molding Circuit Card Assembly Guidelines out there fr
Electronics Forum | Fri May 18 06:49:58 EDT 2012 | kahrpr
We us a lot of 1B31 it could be one of the most common coatings out there. We do not clean the boards and do not have an issue. I would check the solder mask compatibly. I would also see how the 3rd party company is testing the boards what criteria o
Electronics Forum | Tue Feb 19 11:28:29 EST 2013 | pbarton
We use a number of conformal coating materials. When you say you think you want to use a UV material do you mean UV cure, or just material with a UV trace for inspection purposes? For selecting appropriate materials take a look at IPC-HDBK-830. Keep
