LC is simulation tool for the analysis of the electromagnetic properties of electrical interconnects. The full three-dimensional circuit is modeled, so all interactions are automatically included in the solution. The model can be excited by numerous types of waveforms, and the transient response measured using common values such as voltage and current. Circuit parameters such as inductance, capacitance, and impedance can be derived from the transient response, and frequency-domain results such as S-parameters can also be calculated. Far field radiation patterns can be obtained. LC is primarily an electromagnetic simulation and uses the Finite-Difference Time-Domain (FD-TD) technique. FD-TD is a full wave explicit solution of Maxwell's equations in three dimensions. In FD-TD, the rectangular volume enclosing the model is discretized into a large number of small cells, which may be uniformly-sized, or may vary in size within the simulation space. The dielectric, permeable, lossy, and conducting material properties of each cell are incorporated into the field updates, which are performed iteratively in small time steps. An interface between the electromagnetic simulation and the circuit simulation program SPICE is available within LC. This allows the user to add arbitrary SPICE circuits, such as drivers and loads, into the interconnect model. The interconnect performance is calculated using FD-TD while the lumped-element circuits are evaluated by SPICE.