Abstract: The invention is an antenna for use with an implantable microdevice, such as a microstimulator or microsensor, having a dipole antenna that is formed by ceramic processes on the inner or outer surface of the ceramic case of the microdevice. The antenna receives data transmitted from an external device, and transmits data to an external device. A dipole antenna may be formed from two radiating elements separated by an insulating material. A tuning circuit comprising capacitors and/or inductors is used to obtain resonance in the dipole antenna. In a preferred embodiment, the antenna is formed of a biocompatible material by applying a metal-containing paste to the ceramic case of the microdevice and thermally processing it.

Abstract: A circuit may be tuned to resonate at a driving frequency. The circuit includes a source that provides an output at a drive frequency and a resonant circuit having an input coupled to the source, an output, and first and second selectable resonant frequencies. The first resonant frequency is below the drive frequency and the second resonant frequency is above the drive frequency. A control coupled to the resonant circuit output selects the first and second resonant frequencies to cause the resonant circuit to provide an output at an apparent resonant frequency equal to the drive frequency.