RF & PCB

Microstrip Impedance Guide for PCB Design

Understand microstrip impedance, dielectric constant, trace width and high-speed PCB routing.

What is microstrip?

A microstrip is a PCB trace routed over a reference plane.

Impedance parameters

Characteristic impedance depends on trace width, dielectric height, dielectric constant and copper thickness.

Why controlled impedance matters

Incorrect impedance can cause reflections, signal integrity problems and RF mismatch.

Practical PCB notes

Use the stackup from your PCB manufacturer. FR-4 dielectric constant varies with frequency.

Design notes

For accurate RF or high-speed designs, verify with field solvers and measurements.

Use the calculator

Try the related tool and calculate your own values instantly.

Open Microstrip Impedance Calculator