To calculate the differential pair impedance (\(Zd\)):
\[ Zd = \frac{2 \cdot Z0}{\sqrt{1 + \left(\frac{2 \cdot Z0}{Zodd}\right)}} \]
Where:
Differential Pair Impedance is a measure of the opposition to current flow, seen by a signal, in a pair of differential signal traces. It is a key parameter in the design of high-speed digital and analog circuits, as it affects signal integrity, noise immunity, and power dissipation. The impedance is determined by the physical dimensions of the traces, the distance between them, and the properties of the dielectric material separating them. Matching the differential pair impedance to the source and load impedances minimizes signal reflections and maximizes power transfer.
Let's assume the following values:
Using the formula:
\[ Zd = \frac{2 \cdot 50}{\sqrt{1 + \left(\frac{2 \cdot 50}{30}\right)}} \approx 48.04 \text{ Ohms} \]
The differential pair impedance is approximately 48.04 Ohms.
Let's assume the following values:
Using the formula:
\[ Zd = \frac{2 \cdot 75}{\sqrt{1 + \left(\frac{2 \cdot 75}{45}\right)}} \approx 72.06 \text{ Ohms} \]
The differential pair impedance is approximately 72.06 Ohms.
