Based on web pages by Zhi Chang at North Carolina State University.
Modified by Mark Hoffman at Teradyne in May, 2003.


View Calculator
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Motorola formulas

For Dr. Howard Johnson's formulas, see his book, High-Speed Digital Design, pages 430-434. Dr. Johnson got the formulas from his references on page 430.

Microstrip Characteristic Impedance and Capacitance Calculator


Input Parameters
Best with font size = med or 100% Line Width
W=mils
Line Length
L=inches

Line
Thickness
T=mils
H=mils
Dk= Substrate Height
Dielectric Constant
Output Results
Motorola Dr. Johnson
Impedance in Ohms:
Capacitance in pF/inch:
Inductance in nH/inch:
Time in pS/inch:
Resistance in mOhm/inch:
Total Capacitance in pf:
Total Resistance in Ohm:
Warnings:
      (Err > 2% if shown)

Go back to graphical list of geometries.


INSTRUCTIONS
  1. Input parameters (Push calculate to fill in defaults)
  2. Push the CALCULATE button
  3. Then Rock'n'Roll
  4. If necessary, push the CLEAR button