Electronics Forum | Wed Jun 20 07:09:59 EDT 2007 | aj
Hi All, Just a quick question in relation to BGA Stencil Aperture Design - We currently use 1:1 ratio - are there any rules or benefits from over printing the PCB Pad ? Replies appreciated. aj...
Electronics Forum | Mon Jun 25 14:05:12 EDT 2007 | jeffreys
Is anyone out there using a Unit Design ABC-2002 with a RoHS process? If so, what chemistry and concentration are you using and what kind of results are you seeing? TIA.
Electronics Forum | Fri Jul 13 12:27:30 EDT 2007 | jseagle
As in more dwell? We see the same problem with through holes connected to power or ground planes. The solder reaches the plane and stops. We are having our boards re-designed to increase the thermal relief and expand the hole size. We are also tr
Electronics Forum | Thu Jul 19 09:23:52 EDT 2007 | patrickbruneel
Chris, To my knowledge the only difference between leaded and lead-free components is the termination plating. What has changed in the component design that makes them resistant to higher temperatures?
Electronics Forum | Thu Jul 26 23:43:49 EDT 2007 | gioblast
check your stencil design on the ground pad. You might have a big aperture opening that pushing the component away from the paste. Look alos the way your pcb warp. Prioritize side that has component that need flat pcb as much as possible. hope this h
Electronics Forum | Wed Aug 01 19:24:50 EDT 2007 | swag
This board was designed in-house so I was able to get the engineering to move the trace in to a safe distance from the board edge. I think we're good to go.
Electronics Forum | Thu Aug 16 12:52:41 EDT 2007 | russ
DAVE, Does this '7351 supercede the IPC-SM-782?(surface mount design and land pattern standard) how about IPC-CM-770? (guidelines for printed board component mounting) those are the two that I have? Russ
Electronics Forum | Tue Aug 28 14:42:38 EDT 2007 | dphilbrick
You could shoot the engineer that designed them in without having a way to manufacture them. You could also try laser soldering or selective soldering.
Electronics Forum | Tue Sep 04 13:33:55 EDT 2007 | floydf
We "bar" solder them too. (It's really pulsed resistance welding). It's slow but reliable. They seem to be designed for this process. By the way, Luxeon just came out with new LEDs that have nearly the same luminous flux, but that can withstand leadf
Electronics Forum | Wed Sep 05 08:00:37 EDT 2007 | davef
We agree with Doug. Your board needs to be designed with the QFP at a 45* to the wave with scavanger pads in order to wave solder it. Otherwise if you wave solder it, you will need to hire an additional rework person.
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