An electronic article surveillance (EAS) tag/device with coplanar and/or
multiple coil circuits, a tag/device with two or more memory bits, and
methods for making and tuning the resonant frequency of an EAS
tag/device. The device generally includes: an outer inductor having one
end coupled to a capacitor plate; an inner inductor having one end
coupled to an other capacitor plate; a first dielectric film on the outer
and inner inductors and the capacitor plates coupled thereto, having
openings therein exposing other ends of the outer and inner inductors; a
linear capacitor plate and a nonlinear capacitor plate on the first
dielectric film; a second dielectric film containing holes therein for
the second linear and nonlinear capacitor plates, and exposing the other
ends of the first and second inductors; and first and second conducting
straps on the second dielectric film, electrically connecting one of the
exposed inductor ends to a corresponding second capacitor plate.