Electronics Forum | Thu Feb 04 09:09:11 EST 1999 | Peet
| What allowances are people using out there for components off-pad, we currently use 50% of lead width without breaking trace/component clearances but we have a customer demanding 25% allowance ? | We use 50% for civile application, and 25% for mil
Electronics Forum | Fri Nov 09 13:50:50 EST 2001 | Jim Hammes
Any good advice on techniques to properly coat BGA devices on a PCB? Our preference is to spray the boards but I wonder if the coating will do much good. Thanks Jim
Electronics Forum | Tue Dec 04 06:16:50 EST 2001 | Andy
For conventional QFP device, what is the optimun height between lead and pad? 50 microns or 100 microns? What is the factor affecting this height?
Electronics Forum | Wed Aug 21 01:40:42 EDT 2002 | jkhiew
Hi all, Our management set target 50 ppm for overall process like printing,mounting & reflow soldering. Our m/c cpk for mounter is 1.0 & for printing is 1.33. So, pls comment !
Electronics Forum | Mon May 19 19:32:50 EDT 2003 | Dave
Hello. We have a low profile LCC on a board. The clearance is ~ 2mils after reflow. Cleaning away residual flux with an ultrasonic 50C water cleaner caused some LCC and 0201 components to loosen. Should we stay away from the ultrasonic cleaner?
Electronics Forum | Tue Jul 15 21:05:55 EDT 2003 | Thomas
Hi Dave, I saw many of your outstanding comments and postings. Can you save me this time on the profile recommendation ??
Electronics Forum | Wed Jul 16 11:01:58 EDT 2003 | russ
Who is the paste manufacturer? They are the ones who can tell you what to run.
Electronics Forum | Wed May 25 17:42:44 EDT 2005 | jsloot
They are a CP40 and CP50. The CP40 is fairly new and the 50 is fairly new but we bought it as a used piece. It is in good condition. As far as I can say everything seems set up correctly. By the sounds of your reply I should dig into this more deeply
Electronics Forum | Fri Jul 15 16:27:55 EDT 2005 | davef
It depends on how much paste you put on the pads. Assuming your stencil is 1:1 to the pad and the solderability protection on the board is something other than HASL, we'd guess that your solder height is approximately 50% of your stencil thickness,
Electronics Forum | Tue Jul 19 11:21:50 EDT 2005 | russ
You may want to try reducing the large center aperture on your stencil to 50-70% of the area of the pad. This is what we do with QFNs and it may be applicable in this case also.
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