SparkFun Forums

[itamar]

Hi all,

I am designing a 4 layer PCB that needs to have 100ohm impedance. I used an online calculator for defining the needed parameters, however, I'd like to make sure that I can define any prepreg thickness to the fab houses, or do they have standard thicknesses?

Thank you in advance

[robertpeng]

Hi

Prepreg have standard thickness.

My suggestion is design as the online calculator result. If fab houses do not have prepreg with required thickness, they will make very small change to the stackup, they will still meet your impedance control and board thickness requirement.

Hope useful.

Robert-SysPCB