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Re: gEDA-user: improved footprint for MSOP10
Stefan Salewski wrote:
Please try to give more detailed error reports -- if that one is really
wrong, we should remove it.
The spacing of pads in the library footprint, checked visually and in
the editor is very uneven.
The centers of the pads are off the theoretical 0.5mm pitch by 0.1mm or
so, which I find
completely unacceptable. The footprint itself is from the 1-mil-time,
not in 1/100-mil.
Considering that the pad width is 0.3mm, the library version should
really be replaced.
Once agreement on my (modified) version is reached, I'll add the license.
To yours:
Do you really think that it is a good idea to have the text overlapping
the pads by default position?
At least *I* like it more than somewhere outside - I normally move the
refdes anyway to
enable tight packing of parts. If you want, you can put it at the top
left corner.
Well, iirc, this may be a bug with pcb, that wont handle a text position
well in um-mode...
The silk is close to the pads on the left and right side, at least
distance is not symmetric on all four sides.
I took great care to make the part symmetric, so it is. If you mean left
and right margins
are not equal to top and bottom, true.
The reason is, that I kept the dimensions of the libary silk screen and
made the pads
longer for better hand soldering.
Make the silk wider, if you like.
Please note, it is a good idea to specify source of layout data and
license for distribution. PCB footprints can have attributes for that.
The source is probably a datasheet from Linear Technology.
I realized that I left out a license after sending out...
Hexadecimal flags may be OK, but textual ones seems to be preferred in
these days.
Is is really useful to have these thin soldermask areas between pads, or
should we prefer a gang solder mask?
With my manufacturer it is useful. I got the impression, that a gang
solder mask will ruin your day.
I do route on the inside of such a chip and wide solder mask gaps can
lead to unnoticed
shorts on the inside of legs.
This is a question, I am not sure,
but I think there is no real advantage for these stripes, but
manufactures can have problems with it -- ok I think they remove it
anyway.
Piu-Printex doesn't remove the mask - if need be, they fab even smaller.
But then again, they appear to be at the top end in Europe.
'multipcb' didn't complain either.
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