User Guide

LayerStack:
A pack of any number of layers consisting of cores and prepregs which
arehandledtogetherinthecurrentstepofproduction.
Buried Via:
The production process of this via does not differ from a through (nor
-
mal) via. The current layer stack will be drilled through completely. In
the following production steps the already drilled vias can be covered
(buried) by pressing further cores and prepregs on the current layer
stack. If the via is not visible on the completed board we call it a buried
via.
BlindVia:
Blind vias connect an outer layer with any inner layer but don't go
through all copper layers. The specialty of a blind via lies in the produc
-
tion process. The current layer stack is not drilled all through. The drill
hole has a certain depth depending on the number of layers that should
be allowed to be connected with each other. Blind vias have to follow a
given ratio of depth to drill diameter. Please contact your boardhouse to
get information about this. This ratio has to be defined in the Sizes tab
as Min.BlindViaRatio.
MicroVia:
The micro via is a special case of a blind via. It has a maximum depth of
onelayerandaverysmalldrilldiameter.Seepage 131.
LayerSetup
Combining cores and prepregs allows many variants. In the following
sectionsomeexamplesshowthefunctionoftheLayersetup.
Please read this paragraph entirely. Even if you intend to design a four
layer board, for example, it is most advisable to read also all the other
examplesforabetterunderstanding.
4-LayerBoard
Example1:
Layers1,2,3and16areused.
Boardstructure:Onecoreinside,outsideprepregs.
Connections:1-2(blindvias),2-3(buriedvias)and1-16(throughvias)
Thesetupexpressionlookslikethis:
[2:(1+(2*3)+16)]
Explanation:
2*3
Layers2and3formthecore.
(2*3)
Parenthesisallowburiedviasfrom2to3.
125
FromSchematictoFinishedBoard