Re: Problem with SM caps

On Mon, 26 Jan 2009 22:06:23 GMT, Charlie E. <edmondson@xxxxxxxx>
wrote:

On Mon, 26 Jan 2009 14:01:48 -0800 (PST), a7yvm109gf5d1@xxxxxxxxxxx
wrote:

On Jan 26, 4:49 pm, Charlie E. <edmond...@xxxxxxxx> wrote:
Hi All,
Ok, after never before having an opportunity, I designed my new boards
with SM caps. Didn't think there would be any problems soldering
them, but have run into a real problem.

Every single dang one of them shorts out when I solder them down. They
are Murata 0805 caps, and the only thing I can think of, is that there
is this little metal 'clip' on each side that must be shorting the
pads together. if if remove one of the caps, it is definitely not
shorting internally.

I just used the standard 0805 footprints in the Orcad Layout library,
and haven't had any problems with the resistors, just these darned
caps! Has anyone else seen problems like this? Or am I just making
some simple newby mistake?

Thanks,
Charlie

Which part number?
Are the boards clean?
How are the parts being placed? By machine? Pick and place?
How are they soldered? By hand? Reflow?
Are you using lead-free solder?
What kind of solder paste? How big are the mask openings?
Are you using a different footprint for the caps? Maybe there's a
problem with that symbol?

Ok, they are new boards being hand soldered by yours truly. They are
clean, and I am using standard thin (.032) solder from Radio Shack.

Bad new is, I just looked at one that I pulled off the board, and it
IS shorted internally. great, they must be sensitive to solder
temperatures...

BTW, the clip is the end clips, they just have these little bits of
metal holding the sides in.
Charlie

the clips are NOT the end clips...
.

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