AN 958: Board Design Guidelines

ID 683073
Date 6/26/2023
Document Table of Contents Simple Parallel Termination

In a simple parallel termination scheme, the terminating resistor (RT) is equal to the line impedance. Place the termination resistor as close to the load as possible to be efficient. Refer to Figure 29.

Figure 29. Simple Parallel Termination

The stub length from RT to the receiver pin and pads should be as small as possible. A long stub length causes reflections from the receiver pads, resulting in signal degradation. If your design requires a long termination line between the terminator and receiver, the placement of the resistor becomes important. For long termination line lengths, use fly-by termination (refer to Figure 30).

Figure 30. Simple Parallel Fly-By Termination