Dear Technetter,

Graig asked a very good question. I actually experienced problem following the
IPC-2221 table 6.1. Analytically, 0.6mm spacing in column B2 for 100 volt seems
too aggressive when the SIR test (IPC-TM-650 para 2.6.3.3 with coupon IPC-B-24)
guarantees up to only 50V for 0.5mm. Practically we also saw problem with the
100V/0.6mm voltage gradient but our present findings have not been conclusive
yet.

My question is, is the IPC-2221 voltage spacing really in conflict with the SIR
test?

Graig, my apology for opening another can of worms without answering your
question.

K.K. Chin
Artesyn Technologies
Fremont, CA




Craig Hillman <[log in to unmask]> on 06/18/99 03:00:00 AM

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Subject:  [TN] IPC-2221 Table 6.1 Conductor Spacing




I was wondering if anyone could provide me with information on the
research used to determine the conductor spacing requirements of
IPC-2221. More specifically, why is it not material dependent and
is there a safety factor provided in the spacing determination?

Any help would be greatly appreciated.

Thanks in advance,
Craig Hillman
University of Maryland





Dr. Craig Hillman
CALCE Electronic Products and Systems Consortium
University of Maryland
College Park, MD  20742
(301)-405-5316
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