Characterization and test methods for printed circuit board ESD

ESD (electrostatic discharge) from printed circuit boards can be a serious threat to the components on a board. Measurements performed on four representative PCBs (printed circuit boards) indicate that a charged board can discharge a current with tens of amperes and subnanosecond risetimes. In some circumstances discharge current may flow through a single pin of an IC if the discharge is from a point connected to that pin. The discharge current waves in some cases are much higher in amplitude and faster in risetime than the standard test waves used in IC ESD testing. Thus, an IC on a PCB can fail at a much lower ESD voltage level than published ESD ratings would indicate