Re: +3.3,5-board stackup problem

Mike Jenkins (jenkins@lsil.com)
Mon, 07 Jul 1997 11:59:42 -0700

Regarding mesh power planes, one caveat: If the plane uses a diagonal
mesh (i.e., lines at 45 degrees to signal lines), then the ground
current can't follow the signal path directly. This can substantially
reduce the velocity of propagation.

Clearly, a number of other effects (resonance at the mesh pitch,
difficulty of modelling, etc.) are possible. But, I have personally
seen the above effect show up as a nasty surprise.

Mike

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