Electronics Forum | Mon Sep 18 20:51:35 EDT 2000 | Dave F
A fairly dense brickwall would have 0.020" (0.05mm) spacing
Electronics Forum | Thu Dec 07 19:20:28 EST 2006 | ganoi
Most likely there is movement during reflow. How about conduction oven over convection oven for reflow? This is a small PCB with the LED sitting on a Flex-Rigid extension from the PCB. I was thinking if the stencil aperature for the LED was to be cu
Electronics Forum | Tue Apr 04 20:48:37 EDT 2006 | davef
Look here: http://focus.ti.com/lit/ml/slup127/slup127.pdf
Electronics Forum | Thu Oct 20 20:44:15 EDT 2011 | davef
Design based on: * IPC-SM-782A: Gap 0.0157", Pad 0.0354"X0.0276" [along gap] * IPC-SM-782A Mod used on 32411A1 & Volvo Smart Switch: Gap 0.0157", Pad 0.020"X0.020" [along gap] * IPC-7351: Gap 0.008", Pad 0.0256"X0.0256" [along gap]
Electronics Forum | Fri Jan 14 14:59:52 EST 2005 | russ
We use a 25 x 25 mil square pad with a 18-20mil GAP with great success. Russ
Electronics Forum | Tue May 09 14:19:52 EDT 2006 | Larry (not THAT Larry)
Smartasp - What are your lead to hole ratios like? Dial down the flux and open up the holes, if you can. Keeping at least a 14-20 mil gap between min hole/max lead solves the hole fill problem. L
Electronics Forum | Mon Jun 13 14:34:16 EDT 2005 | peter ng
The stencil thickness should be 5.5 mils.The squeeze speed around 20mm/s,print gap 0.15mm,print separation 0.3mm/s.
Electronics Forum | Fri Jan 14 11:16:45 EST 2005 | Dan Gosselin
I have heard of people using a round pad or Home plate design to decrease the incidence of tombstoning on 0402's Anyone have any practical experience on this or is everyone just using the IPC 782 recommended land pattern (28mil x 33mil rectangle pad
Electronics Forum | Wed Feb 09 12:31:54 EST 2005 | russ
We are not doing this right at the moment but I have done it with great success. Of cource it depends on your pad layout we have a 20 mil gap in between pads, we printed at 10 mil wide with a 5mil stencil. I will try to find the glue we used, I kno
Electronics Forum | Thu May 29 17:19:51 EDT 2008 | dyoungquist
On 0402s we use 20x25 mil pads with a 15 mil gap between the pads on the pcb with ENIG finish, 5 mil stencil with a 1:1 aperture (20x25 mil) and SAC305 lead free solder paste. We very rarely see any tombstoning on 0402s using this setup.
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