回波损耗计算器
使用此回波损耗计算器快速获得准确的计算结果。
Copper = 5.8e7, Aluminum = 3.77e7
1 for non-magnetic materials
趋肤深度
0.000066 m
Skin Depth vs Frequency
公式
## What is Skin Depth? Skin depth is the distance into a conductor at which the current density drops to 1/e (about 37%) of its surface value. At high frequencies, current flows mostly near the surface. ### Formula **delta = 1 / sqrt(pi x f x mu x sigma)** Where f is frequency, mu is permeability (mu_0 x mu_r), and sigma is conductivity. ### Practical Impact - At 1 MHz in copper: skin depth is about 0.066 mm - At 1 GHz in copper: about 2.1 micrometers - Conductors for RF need only be a few skin depths thick
计算示例
Copper conductor (sigma = 5.8e7 S/m, mu_r = 1) at 1 MHz.
- 01mu = 1 x 4pi x 10^-7 = 1.2566e-6 H/m
- 02delta = 1 / sqrt(pi x 1e6 x 1.2566e-6 x 5.8e7)
- 03= 1 / sqrt(229.37) = 1 / 15.15 = 0.0660 mm = 66.0 micrometers
常见问题
Why does skin depth matter?
It determines the effective cross-section of a conductor at RF frequencies. Thicker conductors waste material beyond a few skin depths.
How does skin depth affect PCB traces?
At GHz frequencies, only a thin layer of copper carries current. Surface roughness and plating quality significantly affect loss.
What about magnetic materials?
Magnetic materials (mu_r > 1) reduce skin depth dramatically, which is why they are used in shielding applications.
学习