I also use a simple staircase pattern to check layer order and spacing. I make sure that all traces at the edge of the board are ground to avoid any problems. A few strokes with a file are usually all it takes to make them visible. It would be easy to use an aligned pattern of narrow traces on all four sides of the board to check layer alignment. With a microscope measuring to a mil or two should be easy.
> > Are there any tricks, test patterns where I could easily determine the > following for a 16 layer PCB panel without having to > slice up the panel: > > 1) Alignment of each of the middle layers. > 2) Vertical thickness of the copper on the middle layers. > 3) Horizontal thickness of the traces on the middle layers. > 4) Drill hole alignment for all of the layers. >I usually build in a "test coupon" which has, among other things, a "staircase" built in the copper layers (remembering to build the steps in the plane layers in the negative, so you can see thru the dielectric if needed) so that I can verify stacking order, dielectric thickness, and so on, as well as the things you mentioned. You need to instruct the board house not to apply pullbacks between the copper and the edge in this area; easiest is to just be sure to apply your own pullbacks where needed and forbid them to add any. Now, if you can find a way to guarantee they actually READ your fab instructions, you'll really have something! Steve Hendrix
Cheesecote Mountain CAMAC, 24 Halley Drive; Pomona, NY 10970 voice: 845 364 0211, fax: 845 362 6947, www.cmcamac.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/proteledaforum@techservinc.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
