Barbara-

That's usually a job done in CAM--the PCB fab usually will contact you
if they feel like doing it.  Teardropping drastically reduces the
probability that minor breakout due to layer stackup lamination issues,
over etching, or drill mis-targeting will cause a continuity failure.
But if your annular ring is 5mils or greater, the probability is
probably pretty darned small anyway.

Wayne Thayer

>>> [log in to unmask] 7/6/2006 9:17 am >>>


Hey Y'all,



It is my habit to teardrop a trace coming into a through-hole pad if
the
trace is 5 mils or less and the annular ring of the pad is 5 mils or
less.

Does this improve manufacturability of the bare board, protect against
drill-out, and fracturing of the point where the trace enters the pad
under shock and vibration?

Or am I an old-fashioned girl?





Barbara Burcham, C.I.D.

Sr. PCB Designer

RFTrax a Fairfield Co.

[log in to unmask]

281-276-5916

281-276-5950 fax




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