Distributed-element model

The distributed element model or tranmission line model of electronic circuits assumes that each circuit element is finite, as opposed to infinitesimal, and that the wires connecting elements are not perfect conductors -- that is, they have impedance. The model challenges the Lumped element model by assuming non-uniform current along each branch and non-uniform voltage along each node.

This model is more accurate but more complex than the Lumped element model, so it is usually only applied to circuits with wires longer than a few wavelengths of the circuit's operating frequency.