Via Impedance

[IMR]

Hi, I have been using Saturn PCB tools and have noticed that the via calculator has a calculated impedance, is this for high speed routing?

[robertferanec]

Hi IMR, I normally do not match impedance in VIAs and have not seen any problems.

[mairomaster]

It just calculates the impedance of the via. The effect of the impedance though is only seen at high frequencies. At the frequency of the peak impedance you will have the biggest voltage drop around the via. The is a negative effect which often concerns decoupling/power vias for example.

I don't find this calculation particularly useful, but it could be interesting to experiment with different vias and see how the bigger vias for example have smaller inductance, hence are better for decoupling.