Miniaturization of active implantable medical devices is currently compromised by the available means for electrically\r\npowering them. Most common energy supply techniques for implants ââ?¬â?? batteries and inductive couplers ââ?¬â?? comprise bulky\r\nparts which, in most cases, are significantly larger than the circuitry they feed. Here, for overcoming such miniaturization\r\nbottleneck in the case of implants for electrical stimulation, it is proposed to make those implants act as rectifiers of high\r\nfrequency bursts supplied by remote electrodes. In this way, low frequency currents will be generated locally around the\r\nimplant and these low frequency currents will perform stimulation of excitable tissues whereas the high frequency currents\r\nwill cause only innocuous heating. The present study numerically demonstrates that low frequency currents capable of\r\nstimulation can be produced by a miniature device behaving as a diode when high frequency currents, neither capable of\r\nthermal damage nor of stimulation, flow through the tissue where the device is implanted. Moreover, experimental\r\nevidence is provided by an in vivo proof of concept model consisting of an anesthetized earthworm in which a commercial\r\ndiode was implanted. With currently available microelectronic techniques, very thin stimulation capsules (diameter\r\n,500 mm) deliverable by injection are easily conceivable.
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