The following questions relate to ICT (In Circuit Test) of assembled rigid
PWB's
using conventional .050", .075" or .100" probes used in test fixtures.
(Flying probes
are not of interest due to volume of units built).

1) Is there an industry specification that address the air gap required
from the edge
of ICT test pads to SMT component body's and/or component pads?

My dilemma: IPC-SM-782 section 5.7.2 states: "Test lands should be .025
minimum
from mounting land areas." This does not specify the spacing from the
component
body nor does it seem sufficient to the land areas. Our vendors use
IPC-A-610 to
inspect assembled boards. If the assembly is class III and a 1206 resistor
is on the
board IPC-SM-782 section 5.7.2 would seem to allow a test pad to be .010"
under
the part. Obviously, this is not what we want.

2) Is there another industry specification such as IPC, Bellcore, etc. that
addresses this
issue? If so, please indicate the specification #. If you have an internal
specification that
addresses this issue I would be grateful if you could share what your
parameters are.

3) Is there a specification that defines the probe pin accuracy or location
tolerance of
.050", .075" and .100" probes used in a "standard" ICT test fixture?

I've been reading IPC's tech-net and design-net mail for years and there is
a wealth of
knowledge in this mailing list.

Thanks for any help you can provide.
Doug

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