The microstrip width calculator helps determine the exact width of a microstrip trace based on the target impedance, trace thickness and dielectric.
This tool is useful for RF engineers and PCB designers to optimize the performance of microstrip traces.
Formula used
W = (7.48 × H) / exp(Z0 × √(εr + 1.41) / 87) – 1.25 × t
Or :
W = track width (same unit as t and H)
Z0 = target impedance of the microstrip line (Ω)
t = thickness of the track (same unit as H)
H = thickness of the dielectric (same unit as t)
εr = relative dielectric constant of the substrate
Explanation
The width W of a microstrip trace depends on the desired impedance, the thickness of the trace and the dielectric used.
A higher impedance or lower dielectric constant substrate requires a narrower trace, while a thicker trace or higher dielectric constant substrate increases the width needed.
This formula ensures precise design tailored to RF signal requirements.
Calculation example
For a microstrip line with:
Z0 = 50 Ω , t = 0.035 mm , H = 1.5 mm , εr = 4.4 :
W = (7.48 × 1.5) / exp(50 × √(4.4 + 1.41) / 87) – 1.25 × 0.035 ≈ 2.1 mm
Benefits and Use
- Allows you to precisely calculate the width of microstrip tracks according to impedance requirements.
- Useful for RF and microwave circuit board design.
- Helps ensure optimal performance of high frequency signals.
- Makes it easy to adjust design parameters for different substrates and track thicknesses.
