Abstract - A method for predicting stray capacitances
of HF inductors dependent on their geometry is presented. The analysis
is performed for inductors made of one layer of turns with circular
and rectangular cross sections. The wire is uniformly wound around a
cylindrical non-ferromagnetic core. The method is based on an analytical
approach to obtain the turn-to-turn and turn-to-shield capacitances of
coils. The influence of insulating coatings of the wire is also taken
into account. An overall equivalent stray capacitance is derived
according to the typical HF equivalent lumped parameter circuit of
inductors. The method was tested with experimental measurements and
the accuracy of the results was good in most cases. The derived
expressions are useful for designing of HF inductors and can be also
used for simulation purposes.