Online calculator
Characteristic impedance of stripline



Takayuki HOSODA
Dec. 9, 2022

Stripline calculator

Frequency    MHz
Electrical length    deg
Dielectric relative permittivity (εr )   
Dielectric thickness (b )   μm
Conductor thickness (t )    μm
Conductor width (w )     μm
Impedance (Z0) ≈    Ω
Capacitance ≈     pF/m
Inductance ≈     nH/m
Velocity of propagation ≈     
Physical length ≈     mm
Note: The practical ranges for Z0 from 25 to 115 Ω, with possible erros of up to ± 3 %.
stripline-0.21.js — Analyze Stripline. Rev. 0.21 (Jan. 29, 2023) (c) Takayuki HOSODA

Formulas used [1]

For wide traces (w / b ≤ 0.35)
Z_0 &=& \frac{1}{ \sqrt{\varepsilon_r}} \displaystyle\frac{94.15}{ \displaystyle\frac{\displaystyle \frac{w}{b}}{1 - \displaystyle\frac{t}{b} } + \displaystyle\frac{Z_{k1}}{ \pi }}\\ Z_{k1} &=& \frac{2}{1 -\displaystyle \frac{t}{b}}\ln\left(\frac{1}{1 -\displaystyle \frac{t}{b} } + 1\right) - \left(\frac{1}{1 -\displaystyle \frac{t}{b} } - 1\right) \ln \left(\frac{1 }{\left(1 -\displaystyle \frac{t}{b} }\right)^2} - 1\right)
For narrow traces (w / b ≤ 0.35)
Z_0 &=& \frac{60}{ \sqrt{ \varepsilon_r } }\ln\left(\displaystyle \frac{4 b}{\pi \, Z_{k2}} \right)\\ Z_{k2} &=& \frac{w_e}{2}\left(1 + \displaystyle\frac{t}{\pi w_e}\left( 1 + \ln\left( \frac{4 \pi w_e}{t}\right) + 0.51 \pi \left(\frac{t}{w_e}\right)^2 \right) \right) \\ \frac{w_e}{b} &=& \frac{w}{b} - \left(0.35 - \frac{w}{b} \right)^2

REFERENCE

  1. Mohammed K. Hammood, "Impedance of Stripline", Tikrit Journal of Pure Science 17 (4) 2012, ISSN : 1813-1662
  2. "Problems in Strip Transmission Lines," MTT-3, No. 2, March 1955, pp. 119-126.
Powered by
 Finetune