Hi Guys
 I am thinking to use advanced circuit (4pcb.com) service to make tranmission line (MLIN 50 Ohms). However, I can not find info on each layers. If anyone can give me a link or supply info on thickness of each layer, it will be greatly appreciated.
I found the following info on the website.
4-Layer PCB - 0.062" finished thickness

Layer 1 - Copper - 0.0014" thick (1 oz. copper weight)
Laminate (prepreg) - 0.0115"-0.0129" thick - Dielectric Constant of 4.6
Layer 2 - Copper - 0.0014" thick (1 oz. copper weight)
Core material - 0.028" thick - Dielectric Constant of 4.7
Layer 3 - Copper - 0.0014" thick (1 oz. copper weight)
Laminate (prepreg) - 0.0115"-0.0129" thick - Dielectric Constant of 4.6
Layer 4 - Copper - 0.0014" thick (1 oz. copper weight)

Please comments how accurate it is. I added all the layer's thickness together and found it is less than 0.06 inch.
thanks

liletian,

Around 50 to 60 mils is pretty common for a four layer pcb,
Remember that the inner copper layers don't add total height since the prepreg fills the space around the conductor.  

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