On Thu, 04 Oct 2007 00:00:26 GMT, Joerg
wrote:

Eeyore wrote:


Joerg wrote:


I'll second John's and Rich's comments. Besides rounding you might want
to consider flaring the traces into the pin header vias. I think
layouters call that "drop". That way there could be less stress fractures.


Teardrop. It's astonishing how many good practices of old have been lost as a
result of CAD layout.

There was once a Marconi (Instruments) IIRC guide to pcb layout from the early
days of tape-up. It covered all these subtleties. I've seen excerpts but never
the actual publication.

I HAVE seen foil fractures where a thin trace enters a pad resulting from rough
handling, rework or whatever. Tear drops reduce such stresses hugely. It's basic
engineering.

PADS IIRC is the only package I've seen that has a teardrop function built in as
standard.


Eagle can do that as well AFAIK. But I never do layouts myself.

A lot of layout is common-sense and it gets violated a lot. Why on earth
everyone thinks right angle looks more cool that round traces I will
never understand. And then the stuff breaks.


Do you think a right-angle trace is more likely to break than a curve
or bevel? I can't see why.

Except maybe for high voltages, or 5+ GHz stuff, I don't think it
matters.

John