Implantable medical devices and systems having inductive telemetry and recharge on a single coil

• US 9,136,728 B2
• Filed: 04/28/2011
• Issued: 09/15/2015
• 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.
• Primary Examiner(s): Fantu, Yalkew
• Application Number:
  US13/096,073
• Publication Number:
  US 20120274270A1
• Time in Patent Office: 1,601 Days
• Field of Search: 320/108
• US Class Current: 1/1
• 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 that is different than the recharge frequency while the tank circuit is tuned to the recharge frequency;

a controller that is coupled to the tank circuit that tunes the tank circuit to the telemetry frequency and the recharge frequency and that is coupled to the receiver, wherein in response to the controller receiving a recharge instruction obtained from telemetry signals received through the receiver, the controller tunes the tank circuit 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 controller being 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 the recharge 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 recharge 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 that is different than the recharge frequency while the tank circuit is tuned to the recharge frequency;

a controller that is coupled to the tank circuit that tunes the tank circuit to the telemetry frequency and the recharge frequency and that is coupled to the driver circuit, wherein in response to the controller receiving a recharge instruction obtained from telemetry signals, the controller tunes the tank circuit to the recharge frequency prior to the driver circuit producing telemetry signals at the telemetry 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 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 the recharge 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 recharge 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. A method of interaction with an implantable medical device, comprising:

at the implantable medical device, receiving telemetry signals that provide a recharge instruction and tuning a tank circuit to a recharge frequency in response to receiving the instruction;

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

after receiving the telemetry signals that provide the recharge instruction, 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.

18. The method of claim 17, 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.

19. The method of claim 18, further comprising:

at the external recharge device, sending telemetry signals that include the 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 recharge 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.

20. The method of claim 18, 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.

21. The method of claim 20, 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.

22. An implantable medical device, comprising:

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

a receiver having a decoder to decode information from telemetry signals and 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 that is different than the recharge frequency while the tank circuit is tuned to the recharge frequency and to decode the telemetry signals received 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.