constructive critic on my plcc adapter PCB
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.
Graham
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