I've done a lot of research this last year on pcb specs, and have a few
question
concerning high end PCB from here and overseas.
I've noticed through hole components are no where near IPC annular ring
standards
Neither are the surface mount land patterns. PGAs are using alternating
oblong pads.

Here are some facts;
  a.. A board can be built beyond IPC standards and work.
  b.. Annular ring is mostly required for re-work.
  c.. Vias require almost NO annular ring.
  d.. Internal pads annular ring can be the mfg AR or current requirements,
whichever is greater.
Let me make it plain, this is not knocking IPC in anyway, but is it time we
specify and go beyond the
current limitations and expand to some current practices and make some of
the specification
"Technology specific"? (This may already been in the works since I've had my
head buried in work
the last year and haven't been keeping up with recent events)
I've brought up the category of "Soldered thru-holes" and "non-soldered
thru-holes" and have heard
nothing but agreement there.

I've witnessed thru-holes components soldered with great quality to pads
with nothing more than a .
009" AR. Granted, you couldn't remove the component, but it is a throw away
board.
I just keep hearing this question coming to me over and over and I can say,
is if you are comfortable
with the quality, and the components will NOT be removed then there isn't a
problem, just don't specify it
being finished per IPC specifications.

Chris Robertson
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