Electronics Forum | Thu Aug 21 08:15:07 EDT 2008 | naynayno
Thanks Dave, I will be sticking with Manufacturing Engineering. These are good guidelines but what is standard clearance for various packages? This is a dimension we usually seek by eye, whether we will have a problem or not. We use straight DI -
Electronics Forum | Thu Aug 21 08:33:09 EDT 2008 | davef
There is no standard as such. It's easy to see why. It's too complicated and has such a small payoff. Standoff is comprised of: * Package height * Solder thickness between the pad and the component lead * Delta of pad thickness and solder mask For p
Electronics Forum | Wed Sep 12 18:11:03 EDT 2001 | davef
First, what on the area array package are you analyzing � * Package cracking? * Cracked solder balls? * Er, what? Second, most failure analysis discussions consider dye penetration to be a non-destructive test, but then again most failure analysis
Electronics Forum | Mon Jul 16 10:44:29 EDT 2007 | Jacky
Hi All, Recently, we encountered strange defect at our SMT line. We can see solder ball spatter around at one of the component pad. This lead to insufficient solder defect at 1 side of the component. The other side of the component look good(Meet
Electronics Forum | Mon Jul 16 11:25:22 EDT 2007 | davef
For the problem part, describe the pads on the board and the aperatures on the stencil.
Electronics Forum | Mon Jul 16 16:42:40 EDT 2007 | pnguyvu
Hi Jacky, It seems you have solder bead problem, beading occurs when the solder paste brick splatter as a component is placed into it, after reflow, the splatter becomes a spherical solder ball. Hope this will help. Steve USA STENCILS
Electronics Forum | Fri Jul 20 16:39:18 EDT 2007 | john_smith
Jacky, we have had a similar problem. We needed to go to a smaller nozzle and also check your vacuume system and air kiss.Could be after placement when the machine blows air to insure the part is off the nozzle that it is effecting the solder brick.
Electronics Forum | Thu Dec 18 15:48:25 EST 2003 | Subhash Nariani
Hello, Does anyone have experience with the PCB assembly of 0.5mm pitch chip scale packages with HASL finish? Characterization data that you can share? Tribal knowledge has it that the height variations of the solder prevent the use of HASL for fin
Electronics Forum | Fri Dec 16 07:42:05 EST 2005 | pavel_murtishev
Good evening, We noted one more very strange problem with flash memory chips. Device fails test due to flash chip malfunction. From the first sight open joint or cold joint can cause such problem. But all chip legs are soldered well. We just heat th
Electronics Forum | Fri Jun 23 09:36:58 EDT 2000 | C.K.
Chrys: Funny that you mention that, but here at my company, our oven is blamed on almost everything: skewing, tombstoning, solder shorts, etc.... In fact, we often have to tell the supervisors, "It's not the oven because we don't turn the skewing