IMPLANTABLE MEDICAL DEVICES AND SYSTEMS HAVING INDUCTIVE TELEMETRY AND RECHARGE ON A SINGLE COIL

• US 20120274270A1
• Filed: 04/28/2011
• Published: 11/01/2012
• Est. Priority Date: 04/28/2011
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Dinsmoor, David A., Anderson, Joel A.
• Granted Patent: US 9,136,728 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• 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 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries

Abstract

Implantable devices and related systems utilize a single coil for both inductive telemetry at one telemetry signal frequency and recharge at another recharge energy frequency. The coil is included in a tank circuit that may have a variable reactance. During telemetry, particularly outside of a recharge period, the reactance may be set so that the tank circuit is tuned to the telemetry frequency. During recharge, the reactance is set so that the tank circuit is tuned to the recharge frequency. Furthermore, the tank circuit may have a Q that is sufficiently small that the tank circuit receives telemetry frequency signals that can be decoded by a receiver while the tank is tuned to the recharge frequency so that telemetry for recharge status purposes may be done during the recharge period without changing the tuning of the tank circuit.

Claims

1. An implantable medical device, comprising:

a tank circuit tuned to a recharge frequency of recharge energy;

a receiver with at least one input electrically connected to a node of the tank circuit, the receiver being configured to receive telemetry signals at a telemetry frequency while the tank circuit is tuned to the recharge frequency;

a rechargeable power source;

a rectifier that is electrically connected between the rechargeable power source and the tank circuit and that is configured to receive the recharge energy at the recharge frequency; and

medical circuitry electrically connected to the rechargeable power source.

2. The implantable medical device of claim 1, wherein the tank circuit comprises a variable reactance, the implantable medical device further comprising a controller in electrical communication with the variable reactance, the controller comprising logic configured to set the variable reactance to tune the tank circuit to the recharge frequency of recharge energy that is different than the telemetry frequency so that the tank circuit is tuned to the recharge frequency while the receiver is receiving the telemetry signals.

3. The implantable medical device of claim 2, wherein the controller is further configured to implement an instruction to set the variable reactance to tune the tank circuit to the recharge frequency.

4. The implantable medical device of claim 3, wherein the receiver receives the instruction from a telemetry signal at the telemetry frequency while the variable reactance is set to tune the tank circuit to the telemetry frequency.

5. The implantable medical device of claim 2, wherein the controller is further configured to implement an instruction to set the variable reactance to tune the tank circuit to the telemetry frequency.

6. The implantable medical device of claim 5, wherein the receiver receives the instruction from a telemetry signal at the telemetry frequency while the variable reactance is set to tune the tank circuit to the recharge frequency.

7. The implantable medical device of claim 2, wherein the logic sets the variable reactance to tune the tank circuit to the recharge frequency while the receiver is receiving the telemetry signals during a first time period, and wherein the logic sets the variable reactance to tune the tank circuit to the telemetry frequency of the telemetry signals while the receiver is receiving the telemetry signals during a second time period that is distinct from the first time period.

8. The implantable medical device of claim 7, wherein the logic sets the variable reactance to tune the tank circuit to the recharge frequency while the rectifier is receiving the recharge energy during the first time period.

9. An implantable medical device, comprising:

a tank circuit tuned to a recharge frequency of recharge energy;

a driver circuit electrically connected to a node of the tank circuit, the driver circuit being configured to produce telemetry signals at a telemetry frequency while the tank circuit is tuned to the recharge frequency;

a rechargeable power source;

a rectifier that is electrically connected between the rechargeable power source and the tank circuit and is configured to receive the recharge energy at the recharge frequency; and

medical circuitry electrically connected to the rechargeable power source.

10. The implantable medical device of claim 9, wherein the tank circuit comprises a variable reactance, the implantable medical device further comprising a controller in electrical communication with the variable reactance, the controller comprising logic configured to set the variable reactance to tune the tank circuit to the recharge frequency while the driver circuit is producing the telemetry signals.

11. The implantable medical device of claim 10, wherein the controller is further configured to implement an instruction to set the variable reactance to tune the tank circuit to the recharge frequency.

12. The implantable medical device of claim 11, further comprising a receiver electrically connected to at least one node of the tank circuit, wherein the receiver receives the instruction from an incoming telemetry signal at the telemetry frequency while the variable reactance is set to tune the tank circuit to the telemetry frequency.

13. The implantable medical device of claim 10, wherein the controller is further configured to implement an instruction to set the variable reactance to tune the tank circuit to the telemetry frequency.

14. The implantable medical device of claim 13, further comprising a receiver electrically connected to at least one node of the tank circuit, wherein the receiver receives the instruction from an incoming telemetry signal at the telemetry frequency while the variable reactance is set to tune the tank circuit to the recharge frequency.

15. The implantable medical device of claim 10, wherein the logic sets the variable reactance to tune the tank to the recharge frequency while the driver circuit is producing the telemetry signals during a first time period, and wherein the logic sets the variable reactance to tune the tank circuit to the telemetry frequency of the telemetry signals while the driver circuit is producing the telemetry signals during a second time period that is distinct from the first time period.

16. The implantable medical device of claim 15, wherein the logic sets the variable reactance to tune the tank circuit to the recharge frequency while the rectifier is receiving the recharge energy during the first time period.

17. An external recharge device, comprising:

a tank circuit tuned to a recharge frequency of recharge energy;

a receiver with at least one input electrically connected to a node of the tank circuit, the receiver being configured to receive from the tank circuit incoming telemetry signals at a telemetry frequency;

a driver circuit electrically connected to a node of the tank circuit; and

a controller in electrical communication with the driver circuit, the controller causing the driver circuit to drive the tank circuit at the recharge frequency when sending recharge energy and to drive the tank circuit at a telemetry frequency when sending outbound telemetry signals.

18. The external recharge device of claim 17, wherein the controller is further configured to send an instruction via the outbound telemetry signals, wherein the instruction is a request that an implantable medical device tune a receiving circuit of the implantable medical device to the recharge frequency.

19. The external recharge device of claim 17, wherein the controller is further configured to send an instruction via the outbound telemetry signals, wherein the instruction is a request that an implantable medical device tune a receiving circuit of the implantable medical device to the telemetry frequency.

20. A medical system, comprising:

an external recharge device that transmits recharge energy at a recharge frequency from a tank circuit tuned to the recharge frequency and that exchanges telemetry signals at a telemetry frequency that is different than the recharge frequency through the tank circuit tuned to the recharge frequency; and

an implantable medical device that receives recharge energy at the recharge frequency from a tank circuit tuned to the recharge frequency and that exchanges telemetry signals at the telemetry frequency through the tank circuit tuned to the recharge frequency.

21. The medical system of claim 20, wherein the external recharge device sends telemetry signals including an instruction and the implantable medical device receives and implements the instruction to tune the tank circuit of the implantable medical device to the recharge frequency.

22. The medical system claim 21, wherein the implantable medical device receives the instruction from a telemetry signal at the telemetry frequency while the tank circuit of the implantable medical device is tuned to the telemetry frequency.

23. The medical system of claim 20, wherein the external recharge device sends telemetry signals including an instruction and the implantable medical device receives and implements the instruction to tune the tank circuit to the telemetry frequency.

24. The medical system of claim 23, wherein the implantable medical device receives the instruction from a telemetry signal at the telemetry frequency while the tank circuit of the implantable medical device is tuned to the recharge frequency.

25. The medical system of claim 20, wherein the tank circuit of the implantable medical device is tuned to the recharge frequency while receiving the telemetry signals during a first time period, and is tuned to the telemetry frequency while receiving the telemetry signals during a second time period that is distinct from the first time period.

26. The medical system of claim 25, wherein the tank circuit of the implantable medical device is tuned to the recharge frequency while the rectifier is receiving the recharge energy during the first time period.

27. The medical system of claim 25, further comprising an external telemetry device that exchanges telemetry signals at the telemetry frequency with the implantable medical device through a tank circuit of the external telemetry device that is tuned to the telemetry frequency.

28. A method of interaction with an implantable medical device, comprising:

at the implantable medical device, receiving recharge energy at a recharge frequency from a tank circuit of the implantable medical device that is tuned to the recharge frequency; and

at the implantable medical device exchanging telemetry signals at a telemetry frequency that is different from the recharge frequency through the tank circuit of the implantable medical device that is tuned to the recharge frequency.

29. The method of claim 28, further comprising:

at an external recharge device, sending the recharge energy at the recharge frequency from a tank circuit of the external recharge device that is tuned to the recharge frequency; and

at the external recharge device, exchanging the telemetry signals at the telemetry frequency through the tank circuit of the external recharge device that is tuned to the recharge frequency.

30. The method of claim 29, further comprising:

at the external recharge device, sending telemetry signals that include an instruction to tune the tank circuit of the implantable medical device to the recharge frequency;

at the implantable medical device, receiving the telemetry signals that include the instruction through the tank circuit of the implantable medical device while the tank circuit of the implantable medical device is tuned to the telemetry frequency; and

in response to receiving the instruction, tuning the tank circuit to the recharge frequency.

31. The method of claim 29, further comprising:

at the external recharge device, sending telemetry signals that include an instruction to tune the tank circuit of the implantable medical device to the telemetry frequency;

at the implantable medical device, receiving the telemetry signals that include the instruction through the tank circuit of the implantable medical device while the tank circuit of the implantable medical device is tuned to the recharge frequency; and

in response to receiving the instruction, tuning the tank circuit to the telemetry frequency.

32. The method of claim 31, further comprising:

at an external telemetry device, sending telemetry signals at the telemetry frequency to the implantable medical device while the tank circuit of the implantable medical device is tuned to the telemetry frequency.