Weekly PULSE Issue
Kaivan Karimi – Dir. of Global Strategy, Microcontroller Group, at Freescale
Edge Coupled Trace Inductance
Calculate the Inductance of Two Edge Coupled Traces
EEWeb
Edge Trace Inductance Calculator
Choose Type
Edge Coupled Trace Inductance Calculator
Inputs
Trace Width
W
Trace Seperation
S
Trace Length
L
Relative Permeability
μr
Outputs
Inductance:
Introduction
Coplanar traces are common in printed circuit boards. Coplanar traces where one trace is the signal and the other trace is the return path apply to this inductance calcualtor.
Wire Loop Inductance Description
The inductance of the coplanar trace calculation requires 4 variables:
- W – Trace Width
- S – Trace Seperation
- L – Trace Length
- ur – relative Permiablity
This structure requires that these spacings be uniform down the entire length of the trace.
Coplanar Trace Inductance Model.
The inductance of the coplanar trace is:
L_{coplanar}\approx \frac{\mu _{o}\mu _{r}}{\pi}\cosh^{-1}\left ( \frac{s}{w} \right )
Where
\left ( d>>w, w>t \right )
