Bouncing out GROUND BOUNCE

摘要

Let's start with a quick definition of ground bounce. Ground bounce is a transient voltage generated between two different points on the same ground path, such as a package lead, a connector pin or different locations on the ground plane of a circuit board. Any signal paths that use this ground path as part of their return will see the transient ground bounce voltage as noise. The ground bounce voltage noise will appear on all signal lines that share the common return path, whether there is a driven signal on the line or it happens to be pegged low. If a daughtercard is plugged into a connector and there is ground bounce voltage noise on the connector pins, the entire ground of the daughtercard will "bounce" with the noise. If the shield of a cable is connected to a ground plane with ground bounce noise, the shield voltage can bounce with respect to the chassis. This can drive common currents in the shield and contribute to EMI.