As signal rise times continue to increase, a phenomenon called "ground bounce" begins to be an issue. But many people don't know what it is or don't know much about it. Here are some things it isn't. It isn't what happens when Ken Griffy Jr. hits a ground ball. It's not what happens when your checkbook gets really low. And its not what happens in an earthquake. It IS a source of circuit noise and signal distortion that occurs inside an IC package, and therefore is not well understood by some people outside the semiconductor industry.