PCB Differential Pair Calculator
Calculate differential impedance and coupling coefficient for PCB traces.
Results:
Differential Impedance:
Coupling Coefficient:
About this Calculator:
This PCB Differential Pair Calculator helps you determine the differential impedance and coupling coefficient for PCB differential pairs. It's essential for high-speed digital designs using protocols like USB, HDMI, and PCIe.
How to Use:
Enter the trace width, spacing between traces, dielectric thickness, and dielectric constant of your PCB material. Click "Calculate" to see the differential impedance and coupling coefficient.
Equations Used:
The differential impedance (Zdiff) is calculated using:
\[ Z_{diff} = \frac{2}{C_0\sqrt{\epsilon_r}} \ln\left(\frac{4h}{w}\right) \cdot \left(1 - 0.48e^{-0.96s/h}\right) \] where: \[ C_0 \text{ is the speed of light, } \epsilon_r \text{ is the dielectric constant,} \] \[ h \text{ is the dielectric thickness, } w \text{ is the trace width, and } s \text{ is the spacing} \]
The coupling coefficient (k) is calculated as:
\[ k = \frac{s/h}{s/h + 2w/h} \]
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