January 18, 2007 -- Spice is a popular circuit simulator. As electronic designs move to higher frequencies and occupy less space, Spice is often insufficient to predict the behavior of even simple circuits. When this scenario occurs, engineers must turn to the use of field-solver software. Field solvers, sometimes called EM (electromagnetic)-field solvers, calculate Maxwell's equations for a physical representation of your circuit. You must provide the field solver with a representation of the physical configuration of the circuit, which you base on the output of either an IC- or board-layout package or a solid model. The solid model also must include the properties, such as resistance and dielectric constant, of all the materials in the area of interest. Note that field solvers do not solve the quantum-mechanics problem of what occurs in transistors or other active devices. Field solvers instead focus on traces, inductance, capacitance, and the way these devices interact.

By Paul Rako, EDN Technical Editor