I had a PCB board with 8 layers to be fabricated. I have used an opensource deign modified it a bit and want to get them fabricated. The PCB company asked me to provide layer stack and impedance requirements.
In order to make better PCB, please offer me the layer stack for every layer and the impedance requirements.
I am not sure what exactly to reply with specially regarding the impedance requirements
Here is my layers setting in eagle and regarding impedance control I have an A20 soc and DRAM.