garypang
Junior Member level 2
Hi,
Here is a question regarding the PCB Layers. If I have a 4 layers PCB, top layer with high speed (10GHz) signal trace, middle layer 1 is ground plane, middle layer 2 is power plane, and the bottom layer is other normal trace. We can define the thickness of the first layer of substrate (FR4 or Roger) by calculating the impedance of the high speed signal trace (50ohm for single ended and 100ohm for differential pairs).
How about the second and third layers of the substrate? What kind of consideration we need to make to define the thickness of the second and third substrate layers? Are there any guideline in defining the PCB stack?
Thank you and hopefully someone can help in this problem.
Here is a question regarding the PCB Layers. If I have a 4 layers PCB, top layer with high speed (10GHz) signal trace, middle layer 1 is ground plane, middle layer 2 is power plane, and the bottom layer is other normal trace. We can define the thickness of the first layer of substrate (FR4 or Roger) by calculating the impedance of the high speed signal trace (50ohm for single ended and 100ohm for differential pairs).
How about the second and third layers of the substrate? What kind of consideration we need to make to define the thickness of the second and third substrate layers? Are there any guideline in defining the PCB stack?
Thank you and hopefully someone can help in this problem.