Characteristic impedance

This is a calculator for the characteristic impedance of surface wiring. For high-speed signals, surface mount wiring with low effective dielectric constant (i.e., low loss and delay) is recommended. Single 50Ω: DDR data bus, DDR address bus Differential 75Ω: Analog video signal Differential 85Ω: USB, PCI Express Differential 90Ω: DDR DQS, DDR clock Differential 100Ω: Ether, MDII, LVDS, MIPI