SIMULTANEOUS SWITCHING NOISE - INFLUENCE OF PLANE-PLANE AND PLANE-SIGNAL TRACE COUPLING

The paper presents an aspect of simultaneous switching noise (SSN) for CMOS drivers in packages with power distribution planes, The analysis takes into account the interactions between power distribution planes and signal traces, Coupling between these have a significant effect o n the noise and must be taken into account. A model for the interactio n between the signal conductors and the current paths in the power dis tribution planes is presented. The presence of the signal conductors i s seen to have a significant impact on the SSN, The magnitude of the n oise is strongly dependent on the relative positions of the signal con ductors and the power and ground plane pin connections, Power and grou nd planes sufficiently close to each other also have significant mutua l inductive coupling, This coupling will cause noise to be observed in both distribution planes, even though switching current flows in only one plane, This effect is explained.