The simultaneous switch noise (SSN) problem has traditionally been thought of as an

inductance problem. When many silicon drivers on a silicon chip switch at the same

time, current crowds into the chip Gnd inductance or the Chip Vdd inductance.

Ground bounce occurs that is proportional to the inductance in the ground or Vdd

lead and the rate of change of current: V=L*di/dt. This line of thinking has been

effective at solving SSN problems for traditional lead frame packages. Inductance

matrices that account for the mutual inductance between signal, power and Gnd conductors

are combined with silicon driver models in a circuit simulator to produce

the expected noise waveforms for an SSN event