Self resonant transmitting device
A device for powering an implant within a body of a subject from a location external to the subject, wherein the implant requires a threshold rate of power increase in order to operate in at least one mode, may include an antenna configured to wirelessly transmit energy to the implant. The device may also include a power storage unit configured to store energy from a power source incapable of delivering the threshold rate of power increase to enable the implant unit to operate in the at least one mode and a power release unit configured to release a pulse of energy from the power storage unit to the antenna after the power storage unit collects an amount of energy sufficient to enable the implant unit to operate in the at least one mode.
1. A device for transmitting power from a location external to a body of a subject to an implant unit internal to the body of the subject, the device comprising:
an external circuit including an antenna and a self-resonant transmitter circuit adjustable to change a resonant frequency; and
a processor configured to
cause delivery of an impulse of energy to the external circuit to excite the external circuit and generate a signal at a frequency within the external circuit to be transmitted to the implant unit by the antenna, and
adjust the self-resonant transmitter circuit to provide a match between the resonant frequency of the self-resonant transmitter circuit included in the external circuit and the frequency of the signal generated within the external circuit.
2. The device of claim 1 , further comprising:
a power source;
a power storage unit; and
a power release unit,
wherein the power release unit is configured such that, in a first state, the power release unit causes electrical energy to flow from the power source to the power storage unit and, in a second state, the power release unit causes electrical energy to flow from the power storage unit to the external circuit, and
wherein the processor is configured to cause delivery of the impulse of energy to the external circuit by switching the power release unit from the first state to the second state.
3. The device of claim 2 , wherein the processor is configured to switch the power release unit from the first state to the second state to transmit such that the power delivered from the antenna to the implant unit is transmitted in the form of a pulse train.
4. The device of claim 1 , wherein the self-resonant transmitter circuit includes a resonance matching unit, and wherein the processor is configured to control the resonance matching unit to alter the current resonant frequency of the self-resonant transmitter circuit included in the external circuit based on a detected magnitude of power transmitted to the implant unit.
5. The device of claim 1 , further comprising a flexible substrate, and wherein a least a portion of the external circuit is disposed on the flexible substrate.
6. The device of claim 1 , wherein the processor is further configured to adjust a driving frequency of a signal generating circuit so that the frequency of the generated signal matches the resonant frequency of the self-resonant transmitter circuit.