Electronics Forum | Tue Feb 04 17:24:07 EST 2003 | jonfox
we have some pretty tight 0402 placements and our best fix was to reduce the pad (vertically speaking) from .030x.022 to .020x.022. Fewer tombstones and the paste flows out to the edge of the pads nicely. Only difference is that we have a 6mil sten
Electronics Forum | Thu Dec 24 01:38:36 EST 1998 | Chris Grendler
I need advice on a pad design which several other engineers whom I work with would like to try. I think it is an utterly crazy but I can't seem to convince them differently. My current 0402 chip pad sizes on alumina and FR4 substrates are .022"X.
Electronics Forum | Mon Aug 23 12:33:40 EDT 2004 | rlackey
Hi Ozzy, Second one sounds like a 220nf /0.22uf 16v tant. No idea on the first. Rob.
Electronics Forum | Sat Apr 28 11:13:38 EDT 2012 | davef
Yiii, you scared me with that wave soldering 25 thou stuff upfront. Look here, it may help http://www.jlab.org/accel/eecad/pdf/022pulliam.pdf
Electronics Forum | Wed Dec 30 16:04:15 EST 1998 | former co-worker of yours
| I need advice on a pad design which several other engineers whom I work with would like to try. I think it is an utterly crazy but I can't seem to convince them differently. | | My current 0402 chip pad sizes on alumina and FR4 substrates are .
Electronics Forum | Mon Mar 13 08:59:20 EST 2000 | Ashok Dhawan
I could not find a specific clause or section in J-STD-001B which can relates to special requirements in storage, packing and handling of Moisture sensitive devices per J-Std-033 / 786A /-022 . I guess the way ESD is relevant to electronics assemb
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 Mar 13 08:59:20 EST 2000 | Ashok Dhawan
I could not find a specific clause or section in J-STD-001B which can relates to special requirements in storage, packing and handling of Moisture sensitive devices per J-Std-033 / 786A /-022 . I guess the way ESD is relevant to electronics assemb
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 | Tue Nov 11 09:19:17 EST 2008 | davef
By the way you asked the question, we assume that by "reballing" you mean bumping, we should be able to figure that out: * Volume of the ball = ( pi*d^�)/6 = [355/113] *0.6*0.6*0.6]/6 = 0.11mm^3 * Volume of solder required = 2*volume of ball = 2*0.11