Electronics Forum | Mon Feb 14 17:36:37 EST 2005 | griinder
WE ARE USING MIRAE MX240. ON THIS MACHINE, THE FEEDER ADVANCE AND THE FEEDER PITCH IS CONTROLLED BY THE MACHINE/SOFTWARE AS OPPOSED TO THE FEEDER ITSELF. OUR SELECTIONS FOR 24MM FDDERS ARE 4,8,12, 16, AND 24MM.I WAS WONDERING IF THE 20MM PITCH WAS UN
Electronics Forum | Thu Jul 15 18:07:04 EDT 2004 | dwanzek
This has been a tough one to date. Any ideas will help. Problem definition � random QFP144 part not soldering all leads. Percentage fallout is about 1-5% of boards. Usually leads, one or more, on trailing side to the direction of travel does not wet
Electronics Forum | Wed Sep 18 12:31:16 EDT 2002 | dragonslayr
My suggestion is to conduct a Design For Manufacturing (DFM)study on the assembly in question. Pay particular attention to the pad sizes, component lead dimensions and satisfy yourself that those two factors are correct. Given that pads match compone
Electronics Forum | Wed Nov 06 16:31:59 EST 2002 | slthomas
I would also consider paste control (don't take it personally...I always have to get after people about this one), time on the stencil, time between print and reflow, solderability of the component leads, paste volume (that one really got us once....
Electronics Forum | Sat Feb 10 17:12:03 EST 2001 | rpereira
I admit, 16 mil QFP printing is very challenging but if all your control factors (print speed, etc...) are setup correctly (through DOE) extremely high yields can be achieved and more importantly a repeatable and robust product will be manufactured.
Electronics Forum | Thu Sep 16 16:16:16 EDT 1999 | Power Circuits, Inc.
| I am not familiar with the "mil" metric. How many inches is in 1 mil? | | ...or 10 mil? | | 1 mil= .001 inches 10 mil= .010 inches Also, it has nothing to do with metric.
Electronics Forum | Thu Sep 16 16:16:47 EDT 1999 | Earl Moon
| I am not familiar with the "mil" metric. How many inches is in 1 mil? | | ...or 10 mil? | | each mil = .001" Earl Moon
Electronics Forum | Fri Sep 11 14:39:02 EDT 1998 | Earl Moon
| Thanks to all Earl, Mathew and David for the SMT info. I have one more question. Does anybody have a chart listing the standard, industrial spacings? Perhaps listing in each unit, say XX mils = XX Pitch. Or XX mils = XXmm or something of that n
Electronics Forum | Wed Apr 27 02:22:08 EDT 2005 | grantp
Hi, There are a number of things you can try. You are already using 1:1 hole to pad ratio, and that's good as you need the size. I would try an electroform stencil as that will have a smooth side of the aperture and help paste release. Don't use c
Electronics Forum | Wed Apr 27 07:16:40 EDT 2005 | jdumont
Thanks a lot guys. The part dims are in mm by the way. So last night i was looking at the .pcb file and saw that the pad size and stencil are both .013" while the ball on the BGA is .018" (sorry for switching from metric). Is this ok or can i have en
