Implantable power management system

• US 20020140399A1
• Filed: 03/12/2001
• Published: 10/03/2002
• Est. Priority Date: 04/26/1999
• Status: Active Grant

• Current Assignee: Exonix Corporation
• Original Assignee: Exonix Corporation
• Inventors: Barreras, Francisco Jose Sr., Jimenez, Oscar, Echarri, Roberto, Echarri, Guillermo
• Granted Patent: US 6,664,763 B2
• Time in Patent Office: Days
• US Class Current: 320/130
• CPC Class Codes: A61N 1/3708 for power depletion
• 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 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/007194 of the battery

Abstract

The method and system manage power supplied from a charging circuit to a power source in an implantable medical device utilizing measurements of current drain; measurements of elapsed time since the last full charge; calculations of operating time based on the variable of current drain and the variable of the actual capacity of the power source; sensing of voltage level above a certain value; and monitoring of the temperature of the power source during charging and discharging.

Claims

1. A method for managing power supplied from a charging circuit to a power source in an implantable medical device comprising the steps of:

(1) measuring and recording, each charge/discharge cycle of the power source, to obtain the corrected capacity of the power source in order to calculate and display, upon interrogation, the remaining operating time of the implanted device;

(2) providing within the implanted device circuitry for disconnecting the power source for preventing deep-discharging of the power source below safe limits upon reaching a pre-selected low voltage;

(3) providing circuitry for using variable constant current charge rates;

(4) providing circuitry for switching to constant voltage to top-off the power source at the completion of the charge cycle, in order to prevent overcharging beyond safe limits;

(5) providing circuitry for disconnecting the charging circuit from the power source within the implanted device upon the power source reaching a preselected high voltage level; and

,

(6) providing circuitry for full-time RF powered operation, in case of failure of the internal power source or for operation of the implanted medical device requiring extremely high power consumption instead of being powered from the internal power source of the implanted device.

2. The method of claim 1 including the step of:

providing circuitry for transmitting to a remote receiver, via a telephone link, critical data that can be used by the physician and/or the device manufacturer to assess the performance and condition of the rechargeable power source and the implantable medical device.

3. The method of claim 1 including the step of:

providing circuitry for transmitting to the implantable medical device, via a telephone link, new operation parameter value(s).

4. A method for managing the power supplied to a power source of an implantable medical device comprising the steps of:

(a) providing charging circuitry for a power source in an implantable medical device;

(b) selecting from software in the charging circuitry the correct charge/discharge regimen for the specific power source in the implantable device; and

,

(c) charging the power supply with the correct regimen of current and voltage limits for the specific power source.

5. The method of claim 4 including the step of non-invasively up-grading the regimen for charging the power source, by down-loading, via a direct telemetry link or telephone link, new software revisions to the regimen.

6. A method for managing power supplied from a charging circuit to a power source in an implantable medical device comprising the steps of:

detecting whether or not an RF sensor line has switched high or low;

controlling the charging rate;

non-invasively changing the charge high voltage limit;

switching to a constant voltage mode to top off the charge on the power source;

non-invasively changing the low voltage limit when the power source is disconnected during discharge;

disconnecting the power source when it reaches a low voltage limit;

reconnecting the power source upon sensing the transmission of RF energy;

disconnecting the power source upon sensing a high temperature;

reconnecting the power source when the temperature drops to a normal level;

measuring the power consumption of the circuitry for the implantable medical device;

measuring the elapsed time since the last full charge;

tracking the actual capacity of the power source; and

, calculating the operating time left for the implantable medical device.

7. A method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device comprising the steps of:

measuring the current drain of an implantable medical device;

measuring the elapsed time since the last full charge of a power source of the device;

calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time;

calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source;

measuring the voltage of the power source;

signaling the implantable medical device when the power source voltage has reached a certain low value which requires disconnection from the power source;

disconnecting, during discharging, the power source from the implanted medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage;

precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits;

disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage;

sensing when the electromagnetic waves being transmitted by an RF transmitter/charger induce a voltage level above a certain value at an RF receiver of the implanted power management system;

reconnecting power supply inputs of the implanted medical device to the power source upon sensing this induced high voltage level;

monitoring the temperature of the power source during charging and discharging;

disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging;

reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging;

disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and

,

reconnecting the implantable medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

8. The method of claim 7 including the step of:

transmitting to a remote device, via a telephone link, data that can be used by one of a physician or a device manufacturer to assess the performance and condition of the rechargeable power source and the implantable medical device.

9. The method of claim 7 including the step of:

transmitting, via a telephone link to, and setting in, the implantable medical device, new operational parameter value(s).

10. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

measuring the current drain of an implantable medical device.

11. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

measuring the elapsed time since the last full charge of a power source of the device.

12. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time.

13. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source.

14. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

measuring the voltage of the power source; and

, signaling the implantable medical device when the power source voltage has reached a certain low value which requires disconnection from the power source.

15. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

disconnecting, during discharging, the power source from the implanted medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage.

16. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits.

17. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage.

18. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

sensing when the electromagnetic waves being transmitted by an RF transmitter/charger induce a voltage level above a certain value at an RF receiver of the implanted power management system; and

, reconnecting power supply inputs of the implanted medical device to the power source upon sensing this induced high voltage level.

19. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

monitoring the temperature of the power source during charging and discharging;

disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging; and

, reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging;

20. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

monitoring the temperature of the power source during charging and discharging;

disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and

, reconnecting the implantable medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

21. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

measuring the power consumption of the circuitry for the implantable medical device.

22. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

measuring the elapsed time since the last full charge;

26. The system of claim 25 including:

circuitry for transmitting to a remote receiver, via a telephone link, critical data that can be used by the physician and/or the device manufacturer to assess the performance and condition of the rechargeable power source and the implantable medical device.

27. The system of claim 25 including:

circuitry for transmitting to the implantable medical device, via a telephone link, new operation parameter value(s).

29. The system of claim 28 including:

circuitry for non-invasively up-grading the regimen for charging the power source, including circuitry for down-loading, via a direct telemetry link or telephone link, new software revisions to the regimen.

23. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

tracking the actual capacity of the power source.

24. In a method for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

calculating the operating time left for the implantable medical device.

25. A system for managing power supplied from a charging circuit to a power source in an implantable medical device comprising:

means for measuring and recording, each charge/discharge cycle of the power source, to obtain the corrected capacity of the power source in order to calculate and display, upon interrogation, the remaining operating time of the implanted device;

circuitry for disconnecting the power source for preventing deep-discharging of the power source below safe limits upon reaching a pre-selected low voltage;

circuitry for using variable constant current charge rates;

circuitry for switching to constant voltage to top-off the power source at the completion of the charge cycle, in order to prevent overcharging beyond safe limits;

circuitry for disconnecting the charging circuit from the power source within the implanted device upon the power source reaching a preselected high voltage level; and

,

circuitry for full-time RF powered operation, in case of failure of the internal power source or for operation of the implanted medical device requiring extremely high power consumption instead of being powered from the internal power source of the implanted device.

28. A system for managing the power supplied to a power source of an implantable medical device comprising:

charging circuitry for a power source in an implantable medical device;

software in the charging circuitry for the correct charge/discharge regimen for the specific power source in the implantable device; and

,

charging the power supply with the correct regimen of current and voltage limits for the specific power source.

30. A system for managing power supplied from a charging circuit to a power source in an implantable medical device comprising:

means for detecting whether or not an RF sensor line has switched high or low;

means for controlling the charging rate;

means for non-invasively changing the charge high voltage limit;

means for switching to a constant voltage mode to top off the charge on the power source;

means for non-invasively changing the low voltage limit when the power source is disconnected during discharge;

means for disconnecting the power source when it reaches a low voltage limit;

means for reconnecting the power source upon sensing the transmission of RF energy;

means for disconnecting the power source upon sensing a high temperature;

means for reconnecting the power source when the temperature drops to a normal level;

means for measuring the power consumption of the circuitry for the implantable medical device;

means for measuring the elapsed time since the last full charge;

means for tracking the actual capacity of the power source; and

,

means for calculating the operating time left for the implantable medical device.

31. A system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device comprising:

means for measuring the current drain of an implantable medical device;

means for measuring the elapsed time since the last full charge of a power source of the device;

means for calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time;

means for calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source;

means for measuring the voltage of the power source;

means for signaling the implantable medical device when the power source voltage has reached a certain low value which requires disconnection from the power source;

means for disconnecting, during discharging, the power source from the implanted medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage;

means for precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits;

means for disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage;

means for sensing when the electromagnetic waves being transmitted by an RF transmitter/charger induce a voltage level above a certain value at an RF receiver of the implanted power management system;

means for reconnecting power supply inputs of the implanted medical device to the power source upon sensing this induced high voltage level;

means for monitoring the temperature of the power source during charging and discharging;

means for disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging;

means for reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging;

means for disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and

,

means for reconnecting the implantable medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

32. The system of claim 31 including:

means for transmitting to a remote device, via a telephone link, data that can be used by one of a physician or a device manufacturer to assess the performance and condition of the rechargeable power source and the implantable medical device.

33. The system of claim 31 including:

means for transmitting, via a telephone link to, and setting in, the implantable medical device, new operational parameter value(s).

34. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for measuring the current drain of an implantable medical device.

35. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for measuring the elapsed time since the last full charge of a power source of the device.

36. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for calculating the actual capacity of the power source (corrected for fade) based on the variable of current drain and the variable of elapsed time.

37. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for calculating the operating time based on the variable of current drain and the variable of the actual capacity of the power source.

38. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for measuring the voltage of the power source; and

, means for signaling the implantable medical device when the power source voltage has reached a certain low value which requires disconnection from the power source.

39. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for disconnecting, during discharging, the power source from the implanted medical device upon the power source reaching a certain low voltage in order to prevent deep discharging of the power source and subsequent damage.

40. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for precisely limiting the charging voltage to the power source in order to prevent overcharging beyond safe limits.

41. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising the step of:

means for disconnecting, during charging, the power source from the charging circuit upon the power source reaching a certain high voltage in order to prevent overcharging of the power source and subsequent damage.

42. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for sensing when the electromagnetic waves being transmitted by an RF transmitter/charger induce a voltage level above a certain value at an RF receiver of the implanted power management system; and

, means for reconnecting power supply inputs of the implanted medical device to the power source upon sensing this induced high voltage level.

43. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for monitoring the temperature of the power source during charging and discharging;

means for disconnecting the charging circuitry from the power source if the temperature of the power source raises above a certain level during charging; and

, means for reconnecting the charging circuitry to the power source when the temperature of the power source drops below a certain low value during charging;

44. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for monitoring the temperature of the power source during charging and discharging;

means for disconnecting the implanted medical device from the power source if the temperature of the power source raises above a certain level during discharging; and

, means for reconnecting the implantable medical device to the power source when the temperature of the power source drops below a certain low value during discharging.

45. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for measuring the power consumption of the circuitry for the implantable medical device.

46. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for measuring the elapsed time since the last full charge;

47. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for tracking the actual capacity of the power source.

48. In a system for managing power supplied from a charging circuit of a power management system to a power source in an implantable medical device, the improvement comprising:

means for calculating the operating time left for the implantable medical device.