Hmmm -- I thought that boards had to be created from layer pairs
I didn't know that a 7 layer could be easily constructed, and hence
cost less than an 8 layer board. (I am a novice at these things --
please correct me if I am wrong. I thought a board was constructed
by etching metal on either side of a "core" and then pressing it
together with "prepreg" in between. This would suggest an even
number of layers).
I also thought that to keep a board from warping, you wanted a
stackup that was symmetrical. So having planes 2 and 3 towards
the top and only plane 6 towards the bottom was also a cause for
concern. How big does a board have to be for this to be a concern?
Thanks (a lurker).
-- Christopher Donham Silicon Graphics, VSG Phone: (415) 933-2474 2011 N. Shoreline Blvd MS 43U-993 FAX: (415) 932-2474 Mountain View, CA 94043-1389 E-Mail: firstname.lastname@example.org