Electronics Forum | Tue Dec 28 09:52:28 EST 2010 | flipit
Use a 0.002" to 0.003" thick stencil. Use an electroformed stencil from Photo Stencil or one of the others. Use -500 +635 paste or a -500 paste or type 5 or greater paste. I have printed at 0.008" pitch with 0.004" pads. It can be done.
Electronics Forum | Tue Jan 14 13:26:28 EST 2014 | emeto
You can also see this: http://www.efd-inc.com/NR/rdonlyres/7C8592BD-70D0-4A0A-91C4-2A2743EB6710/0/EFDFrequentlyAskedQuestions.pdf
Electronics Forum | Wed Sep 12 03:52:45 EDT 2018 | shascoet29
Hi, Is the IPC-A-610 applicable to CSP assemblies? Especially regarding the solder ball to solder ball distance versus the minimum electrical clearance for assembly(0.13mm/IPC-A-610). With a 0.4mm pitch component and 260 microns diameters balls, thi
Electronics Forum | Tue Mar 16 03:28:18 EST 1999 | Scott Davies
Al, In general, I would agree with Justin, i.e. contact printing with a 0.007" stencil is great for 0603 - 1206 size components. However, we also place 0.025" pitch QFP components. We use a 0.006" laser cut stencil and I have found through trial an
Electronics Forum | Wed Mar 01 16:59:44 EST 2000 | Dave F
Robert: Expect a 0.033" raw ball to be within 0.022" of the pad, after reflow. To be clear, that�s not a matter of shrinking by 33%. The volume of solder on the pad is the same as the volume of solder in the raw ball. It�s just that the solder is
Electronics Forum | Wed Mar 01 16:59:44 EST 2000 | Dave F
Robert: Expect a 0.033" raw ball to be within 0.022" of the pad, after reflow. To be clear, that�s not a matter of shrinking by 33%. The volume of solder on the pad is the same as the volume of solder in the raw ball. It�s just that the solder is
Electronics Forum | Mon Jun 18 21:20:17 EDT 2001 | davef
It�s sometimes tough to put enough paste on the board before reflow to obtain half-way adequate hole fill with components on a 0.062 inch thick board. So, a 0.093 incher, um. Yano, a lot is determined by board lay-out and how you jigger your profil
Electronics Forum | Thu Jun 22 10:27:26 EDT 2000 | Igmar
Can someone please help with the aperture size on a Micro BGA stencil. I want to have an electroformed stencil made with 0.1mm (4mil) thickness. The PCB pad for the micro BGA has a 0.406mm (16mil) diameter. What size should I make the apertures for t
Electronics Forum | Mon Jun 26 08:54:35 EDT 2006 | dougs
We have a new product in where a 0.7mm pitch uBGA is to be placed on a 2 layer flexi board. Also a 20thou pitch connector. Has anyone done anything like this before, what should i look out for. Not done much flexi work before so any tips will be g
Electronics Forum | Tue Sep 06 12:39:06 EDT 2011 | deanm
According to IPC-7351A, the optimum fiducial is a solid circle with a minimum of 1mm diameter, but can be up to 3mm. There should be a solder mask clearance a minimum of 2x the radius of the copper circle. So the minimum fiducial size is 0.040" with
