ESD protection characterization by an extended Wunsch-Bell plot

Extensive knowledge of the protection device's behavior under electrostatic discharge stress is mandatory to characterize protective elements and systems. This paper gives a brief overview on different electrostatic discharge protection concepts, including general considerations on diverting stress, trigger mechanisms, and their limitations. The protection approaches have to be selected in conjunction with the operational signals to avoid malfunction, increased power consumption, or physical failure. The Wunsch-Bell model is extended by means of an additional axis incorporating the rise time to better characterize different protective circuitry from component- to system-level. This allows for more accurate prediction of system robustness possibly preventing costly re-designs.