Calculate skin effect at high frequencies
Skin Depth (δ)
at 100 MHz in Copper
Skin Depths in Trace
5.30
Effective Thickness
13.22 µm
AC/DC Resistance Ratio
2.66×
Resistance Increase
+166.1%
Values for copper at 20°C
At high frequencies, alternating current tends to flow near the surface of a conductor rather than uniformly through its cross-section. The skin depth (δ) is the depth at which the current density has decreased to about 37% (1/e) of its surface value.
For high-frequency PCB design, skin effect means that increasing copper thickness beyond ~2-3 skin depths provides diminishing returns for reducing AC resistance. Instead, wider traces or smoother copper surfaces may be more effective for reducing RF losses.