No, I don't see how hatching could help at all, you would just be losing the
benefit of the planes coupling together well, and the impedance would be
less (and probably mismatched if you don't test/calculate for it) because
the trace is travelling over "gaps" in the plane.
The only benefit I could see to hatching is less warpage in some cases, and
maybe better bond strength for weird materials
Hmmmmm... am I forgetting something?

onward thru the fog,    Jack


        -----Original Message-----
        From:   Scott D. Shepard [SMTP:[log in to unmask]]

        Let's say that 4 layers is the max(I have no other choice - cost...)
but
        EMC is still a requirement. Would hatching the pwr and gnd planes be
an option
        that would actually help?



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