Microstrip Transmission Line Characteristic Impedance Calculator

The characteristic impedance (Z_o) of a microstrip transmission line can be calculated using the active calculator or the equations at the bottom of the page.

[diagram of PCB layers]

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The following equations are from an article by Rick Hartley page 27 http://www.jlab.org/accel/eecad/pdf/050rfdesign.pdf

The equations give results within 3% of the results obtained in http://www.polarinstruments.com/support/cits/IPC1999.pdf

More calculators for transmission line can be found at http://www.circuitsage.com/tline.html

[calculation equation]

Where ε_r is the Relative Dielectric Constant

W is the Width of track

t is the Thickness of track (1 oz/ft² = 0.035 mm)

h is the Thickness of dielectric

This calculator is provided free by Chemandy Electronics in order to promote the FLEXI-BOX

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	INPUT DATA

Relative Dielectric Constant ( ε_r):
Track Width:	mm
Track Thickness:	mm
Dielectric Thickness:	mm

	RESULTS

Effective Dielectric Constant (ε_eff):
Characteristic Impedance (Z_o):	Ohms