Magnetics Designer is a standalone software program for Windows that designs all types of layer (and sector/split bobbin) wound transformers and inductors, and generates a corresponding SPICE model.

Typical design applications include high frequency switching regulator transformers and output chokes for off-line, full-wave and forward converters, 60 Hz single-phase line transformers, AC inductors, planar magnetics and 400 Hz aircraft transformers. Virtually any single phase, layer wound inductors or transformers that range from 10Hz to over 5MHz can be synthesized with Magnetics Designer.

Magnetics Designer produces a complete transformer or inductor design based upon electrical specifications, including a winding sheet report and a SPICE-compatible model with parasitics.

To start a design, you first select the core family and material. After you enter the operating frequency, the Core Wizard function will select the best core for the job. You may browse through the core database and choose an alternate core, if desired. You can lock the selected core geometry or let the program alter it during the optimization process. Finally, the electrical specifications such as voltage and current per winding are entered on the Transformer screen.
MDTransformerEnter Design specifications for Inductor or Transformers


“Apply” button starts the transformer design process.

Magnetics Designer uses proprietary algorithms to select the appropriate core, number of turns and wire size. This is done to minimize total power dissipation for a given temperature rise in the smallest possible core. The program takes into account design constraints such as the maximum allowed window fill, peak flux density and temperature rise.
Once finished, Magnetics Designer will provide a summary of the cores it tried to optimize, and suggests on how to possibly improve the design if design constraints were not met.
History window indicates major steps of optimization.


“Bobbin” tab shows a cross section of the bobbin core, with windings. Red horizontal lines show insulation, black/grey lines indicate field strength.
The program predicts magnetizing and leakage inductance, inter-winding capacitance, peak flux density, DC winding resistance, high frequency AC resistance (including proximity effects and skin effect), copper loss (both AC and DC), core loss, weight, temperature rise, layer fill and window fill percentage.


A database with thousands of cores, wide variety of materials and wire is included, including a non-linear saturable core SPICE model. In addition, you can add your own cores, wire and material information using a supplied Excel© spreadsheet. Core vendors such as TDK, Magnetics, Philips, Thomson, Micrometals, Siemens, Kaschke, Ferrite International, VAC and Fair-Rite are represented.

Further, formvar, square or double square magnet wire, Litz wire, PCB traces, or foil can be selected. Specialized wire types like those used in planar magnetics can also be added.

Browse the library using the “Core” tab. User can select core (lock geometry), or let the software select the best core.