A planar inductor is a helical PCB trace, residing under a ferrite magnetic core installed on the PCB. Planar inductors can be overlapped on multilayer boards to design planar transformers on the printed circuit board.
PCB layout software packages typically have trouble directly drawing complex curved routes like spirals, splines, and ellipses, but advanced packages do have the ability to import DXF files. One aproach to drawing planar inductors is to:
Draw the shape in AutoCAD, export as a DXF.
Import the trace into the layout package, set up widths, and assign the net.
