The Evolution Of Simulation Technology and Impedance
When design engineers started using simulation toolsets, we originally cared only about impedance and terminations. Then when things got fast, we had to worry about loss in the path. Next, we had to address differential pairs (which are specialized transmission lines) and skew. Most recently, we have had to worry about the effect of vias at very high data rates. Note: Of all of these elements, skew is the only one which cannot be simulated. From