PCB Trace Impedance Calculator
Calculates the characteristic impedance and perunitlength parameters
of typical printed circuit board trace geometries.
Select a configuration:
Microstrip Trace
Embedded Microstrip Trace
Stripline Trace
Dual Stripline Trace

Geometric Parameter Definitions:
W: 

trace width 
T: 
trace thickness 
H (/H1) 
height of trace or dielectric above return plane 
C: 
distance between the differential stripline pair 
er: 
relative permittivity of the dielectric 
Electrical Parameter Definitions:
Zo: 

characteristic impedance 
Zc: 
effective characteristic impedance including the capacitance of distributed loads 
Tpd: 
propagation delay 
Lo: 
inductance per unit length 
Co: 
capacitance per unit length 
Acknowledgements:
The source for formulas used in this calculator (except where otherwise noted) is the Design Guide for Electronic Packaging Utilizing HighSpeed Techniques (4th Working Draft, IPC2251, February 2001.
THESE FORMULAS ARE APPROXIMATIONS! They should not be used when a high degree of accuracy is required.
This transmission line calculator was based on a concept developed by Douglas Brooks of UltraCAD Design, Inc.

