A java utility for generating helical or polygonal inductor footprints in either gEDA footprint or Kicad legacy module format.
The user can quickly and easily generate a helical or polygonal PCB inductor of specified dimensions using command line options.
Users can then add suitable pins or tracks with a footprint editor or text editor to effect connections to adjacent components.
Users will typically have a required inductance in mind, for which a certain number of turns, line spacing, track width, copper thickness and PCB material will provide the necessary inductance.
The utility now calculates distributed capacitance and inductance for the inductor, as well as the resulting self resonant frequency, assuming an FR4 substrate and 35 micron (1 oz / ft^2) copper.
The utility also calculates DC resistance for 35 and 70 micron track thicknesses.
download SpiralInductorFootprintGenerator.java to a working directory
compile it using a java compiler
the resulting java class file can be used with a runtime java virtual machine implementation
java SpiralInductorFootprintGenerator -option value -k export a kicad module, default is geda .fp file -vN export an N-gonal inductor instead of default helical inductor i.e. -v3 for triangle, -v4 for square, -v6 for hexagon -i long inner diameter of coil in microns -o long outer diameter of coil in microns -w long track width in microns -n long number of turns -l long length of segment used to approximate circular arc in microns -h prints this
java SpiralInductorFootprintGenerator -n 40 -i 15000 -o 50000 -w 250 -l 3000 generates a 40 turn helical inductor footprint, of 15mm inside diameter, 50 mm outside diameter, with 0.25mm track width and 3mm segment length. java SpiralInductorFootprintGenerator -n 40 -i 15000 -o 50000 -w 250 -v5 generates a 40 turn pentagonal inductor footprint, of 15mm inside diameter, 50 mm outside diameter, with 0.25mm track width.
SpiralInductorFootprintGenerator.java v1.0 Copyright (C) 2015 Erich S. Heinzle, firstname.lastname@example.org
see LICENSE-gpl-v2.txt for software license This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.