Grounding (SBC Lynx)

Info Box Applies to SBC Lynx

Introduction

SBC Lynx can be used either as a standalone board or as a part of a bigger system. From the point of view of overall system grounding, requirements may differ significantly depending on the actual usage. For this reason, SBC Lynx implements a flexible grounding scheme that can be adjusted to the majority of application environments.

The following image shows the generic organization of ground domains.

Simplified organization of ground domains

Basically, there are three main domains:

• common ground (green area in the picture): all of the digital/analog signals and power supply voltages are referred to this ground
• AC ground (light blue area): it is implemented as a guard ring along the boundary of the board
• connector shields (gray areas): several connectors having a metal chassis and that are located along the edges of the board.

This document describes the most common configurations that differ depending on how these domains are connected to each other. In case you need a configuration that is not listed here, please contact Sales department.

Unified ground

In this configuration all of the three main domains are DC-connected together. This the typical configuration that is used when no earth ground connections are available.

This is the default configuration.

Separated common and AC ground

This configuration is available on request.

In this case:

• AC ground and connector shields are DC-connected together
• AC ground and common ground are AC coupled.

This the typical configuration that is used when

• earth ground connection is available
• AC ground is connected to earth ground. As such, connector shields are DC-connected to earth ground as well.