Jack,

I don't currently have the most recent copy of that standard either.

What I can mention is that regardless of the minimum size listed in the standard manufacturing groups always prefer to develop more robust test systems; larger pads with greater pitch allows for use of test pins which last longer (pretty certain this isn't breaking news to you).

When working at a large OEM our local testability standard was to provide 0.040" pads on 0.100" pitch wherever possible. Pad sizes and pitches were reduced first locally then globally to as low as 0.030" @0.050" centers. Fixtures employing smaller features required frequent maintenance and replacement. Test strategy was 100% nodal coverage via ICT and the fit was good for the technology level of the products.

The vast majority of designs I am currently working on are impossible to achieve 100% coverage rendering pure ICT ineffective. Providing ICT access to connectors, power rails, and JTAG for functional testing as well as AOI and AXI is the best solution for these higher density designs.

Hth,
Dave

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