4PCB.COM Chart showing some prepreg thicknesses related to signal- planes and cu thickness.

 

The chart below provides the thickness for a single ply (sheet) of each style of
Pre-Preg after processing.
These are grouped by the weight and type of the internal conductor layer (typical signal and plane layers) that they will be adjacent to (columns A-F). 

Those that are adjacent to the top and bottom copper layers will use the column
designated for these (column G) regardless of the layer type.
All plies that are not directly against a conductor layer (use for situations with more than 2 plies in an opening), will use the additional plies values (column H).
These values are based on a minimum of 2 plies of pre-preg per opening between foil and cores or between cores.

 

This thickness guide is provided as a guide only. The actual thickness will be
affected by the copper distribution within the design as well as within the
production panels

 

 

A B C D E F G H

Pre-Preg
Styles

Against corewith .5 oz copper and
signal traces
utilizing 30% of
the board area
Against core
with .5 oz
copper and
plane utilizing
70% of the
board area
Against core
with 1 oz
copper and
signal traces
utilizing 30% of
the board area
Against core
with 1 oz
copper and
plane utilizing
70% of the
board area
Against core
with 2 oz
copper and
signal traces
utilizing 30% of
the board area
Against core
with 2 oz
copper and
plane utilizing
70% of the
board area
Against the top
and bottom
copper layers
(foil)
Additional
plies that are
not directly

against
conductor
layers
106 0.0483 0.0559 0.0381 0.0508 0.0127 0.0381 0.0584 0.0533
1080 0.0660 0.0711 0.0533 0.0660 0.0280 0.0559 0.0762 0.0686
2113 0.0889 0.0940 0.0762 0.0889 0.0508 0.0787 0.0991 0.0889
2116 0.1194 0.1245 0.1067 0.1194 0.0813 0.1092 0.1295 0.1168
7628 0.1651 0.1727 0.1524 0.1651 0.1270 0.1549 0.1753 0.1575

All above thickness values are in mm.

The spacing between the top layer and the signal core would finish at about 0.22mm. 
From the ground core to the bottom foil would be approximately 0.226mm.
Add to that the core thickness of 0.97mm at the four layers of 1 ounce Cu at 35um each.

Cu 4 x 35um......................0.140
Core................................1.000
Prepreg top.......................0.222
Prepreg bottom..................0.226
--------------------------------------------------
Final Thickness..................1.6mm  +/-10%
___________________________________

 

 

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