MULTI-LOOP IMPLANT CHARGER

• US 20180262037A1
• Filed: 03/09/2017
• Published: 09/13/2018
• Est. Priority Date: 03/09/2017
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Meskens, Werner
• Granted Patent: US 10,530,177 B2
• Time in Patent Office: Days
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

Presented herein are techniques for charging a battery within an implantable component (implant) of an implantable medical device system. A multi-loop external charging device includes a plurality of coil/loop antennas that are each configured to emit a magnetic field that is received by an implantable coil of the implantable component. At least one characteristic (e.g., phases, amplitudes, etc.) of the emitted magnetic fields are varied relative to one another over time.

Claims

1. A method for wireless transfer of power from a wireless charger to an implantable component having an implantable coil, the method comprising:

delivering a first alternating current signal to a first coil antenna of the wireless charger so as to produce a first magnetic field;

delivering a second alternating current signal to a second coil antenna of the wireless charger so as to produce a second magnetic field, wherein the second alternating current signal causes at least one of the phase or amplitude of the second magnetic field to vary with respect to the phase or amplitude of the first magnetic field; and

receiving, at the implantable coil, a combined magnetic field comprised of the first and second magnetic fields, wherein the combined magnetic field generates an alternating current signal at the implantable coil.

2. The method of claim 1, wherein the combined magnetic field generates an alternating current signal at the implantable coil that has a magnitude that varies over time.

3. The method of claim 1, further comprising:

continuously varying at least one of the phase or amplitude of the second alternating current signal relative to the phase or amplitude of the first alternating current signal.

4. The method of claim 1, further comprising:

varying at least one of the phase or amplitude of the second alternating current signal in a discontinuous manner relative to the phase or amplitude of the first alternating current signal.

5. The method of claim 4, wherein varying at least one of the phase or amplitude of the second alternating current signal in a discontinuous manner comprises:

randomly varying at least one of the phase or amplitude of the second alternating current signal relative to the phase or amplitude of the first alternating current signal.

6. The method of claim 1, further comprising:

varying both the phase and amplitude of the second alternating current signal relative to the phase and amplitude, respectively, of the first alternating current signal. The method of claim 1, further comprising;

delivering a third alternating current signal to a third coil antenna of the wireless charger so as to produce a third magnetic field, wherein the third alternating current signal causes at least one of the phase or amplitude of the third magnetic field to vary with respect to the phase or amplitude of one or more of the first and second magnetic fields.

9. The method of claim 1, wherein the first and second alternating current signals are generated without feedback from the implantable component.

8. The method of claim 7, wherein the first and second coil antennas are positioned within a first plane and the third primary coil is positioned in a second plane.

10. An external charger device for an implantable medical device, comprising:

at least first and second coil antennas configured to generate first and second magnetic fields, respectively; and

a coil excitation system connected to the first and second coil antennas and configured to independently drive the first and second coil antennas so that at least one characteristic of the first magnetic field varies, over time, with respect to the same at least one characteristic of the second magnetic field.

11. The external charger device of claim 10, wherein the coil excitation system is configured to independently drive the first and second coil antennas so as to continuously vary the at least one characteristic of the first magnetic field with respect to the same at least one characteristic of the second magnetic field.

12. The external charger device of claim 10, wherein the coil excitation system is configured to independently drive the first and second coil antennas so as to randomly vary the at least one characteristic of the first magnetic field with respect to the same at least one characteristic of the second magnetic field.

13. The external charger device of claim 10, wherein the at least one characteristic comprises a phase of the first and second magnetic fields, and wherein the coil excitation system is configured to independently drive the first and second coil antennas so that the phase of the first magnetic field varies with respect to the second magnetic field.

14. The external charger device of claim 10, wherein the at least one characteristic comprises an amplitude of the first and second magnetic fields, and wherein the coil driver is configured to independently drive the first and second coil antennas so that the amplitude of the first magnetic field varies with respect to the second magnetic field.

15. The external charger device of claim 10, wherein the at least one characteristic comprises a plurality of characteristics, and wherein the coil excitation system is configured to independently drive the first and second coil antennas so that the amplitude of the each of the plurality of characteristic of the first magnetic field varies with respect to the second magnetic field.

16. The external charger device of claim 10, further comprising:

a third coil antenna configured to generate a third magnetic field, wherein the coil excitation system is connected to the third coil antenna and configured to drive the third coil antenna so that at least one characteristic of the third magnetic field varies, over time, with respect to the same at least one characteristic of one or more of the first and second magnetic fields.

17. The external charger device of claim 16, wherein the first and second coil antennas are positioned within a first plane and the third coil antenna is positioned in a second plane.

18. An implantable medical device system, comprising:

an external charger including;

at least first and second external coil antennas in close proximity to one another and configured to emit first and second magnetic fields that collectively generate a combined magnetic field having a combined magnetic field vector; and

a coil excitation system connected to the first and second coil antennas and configured to drive the first and second coil antennas with time variant waveforms to cause fluctuation in an orientation of the combined magnetic field vector.

19. The implantable medical device system of claim 18, wherein the coil excitation system is configured to drive the first and second coil antennas with time variant waveforms to cause rotation of the combined magnetic field vector.

20. The implantable medical device system of claim 18, wherein the coil excitation system is configured to drive the first and second coil antennas with time variant waveforms that cause the phases of the first and second magnetic fields to vary relative to one another over time.

21. The implantable medical device system of claim 18, wherein the coil excitation system is configured to drive the first and second coil antennas with time variant waveforms that cause the amplitudes of the first and second magnetic fields to vary relative to one another over time.

22. The implantable medical device system of claim 18, wherein the coil excitation system comprises an open-loop control system that is configured to generate the first and second drive signals in the absence of feedback from an implantable component.

23. The implantable medical device system of claim 22, wherein the implantable component includes an implantable coil and wherein the external charger is configured to detect when a voltage at the implantable coil voltage begins to drop.