Method and apparatus for predicting end of battery life

• US 20070040449A1
• Filed: 06/06/2006
• Published: 02/22/2007
• Est. Priority Date: 08/16/2005
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Spurlin, Jon, Gablenz, John, Mehta, Kaezad
• Granted Patent: US 7,737,581 B2
• Time in Patent Office: Days
• US Class Current: 307/64
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61M 2205/3553 remote, e.g. between patient's home and doctor's office
• CPC Class Codes: A61M 2205/3561 local, e.g. within room or hospital
• CPC Class Codes: A61M 2205/3576 with non implanted data transmission devices, e.g. using external transmitter or receiver
• CPC Class Codes: A61M 2205/3584 using modem, internet or bluetooth
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/581 by audible feedback
• CPC Class Codes: A61M 2205/80 voice-operated command
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2209/01 Remote controllers for specific apparatus
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• CPC Class Codes: H02J 9/061 for DC powered loads

Abstract

A powering subassembly for a portable electronic device includes a main battery, a converter, a backup battery, and a controller. The main battery provides a main voltage and the backup battery can provide a backup voltage. The converter receives the main voltage and increases the main voltage to at least one operating voltage. The controller receives the operating voltage from the converter, monitors the voltage of the main battery, and compares the monitored main battery voltage to a main battery low voltage threshold. The controller transmits a disconnect signal to decouple the main battery from the converter if the monitored voltage from the main battery is less than the main battery low voltage threshold. The controller transmits a connection signal to couple the backup battery to the converter if the monitored voltage is less than the main battery low voltage threshold. The backup battery provides the power for a predetermined minimum amount of time.

Claims

1. A method of providing backup power to a portable electronic device, comprising:

monitoring a battery level of a primary battery;

generating a first signal to cause the primary battery to be disconnected if the battery level of the primary battery is less than a low battery threshold voltage; and

generating a second signal to cause the backup battery to provide power for the portable electronic device, wherein the backup battery provides power for operating the portable electronic device for a predetermined minimum time.

2. The method of claim 1, wherein the backup battery provides power to allow the portable electronic device to operate with full feature functionality.

3. The method of claim 1, wherein the generation of the first signal and the second signal occur substantially simultaneously.

4. The method of claim 1, wherein the low battery threshold voltage is less than 1.0 volt.

5. The method of claim 1, wherein the low battery threshold voltage is less than 0.8 volts.

6. The method of claim 1, wherein the battery level and the low battery threshold are both values of a current supplied by the primary battery.

7. The method of claim 1, wherein the portable electronic device is an insulin pump.

8. A method of providing power to a portable electronic device, comprising:

detecting whether a main battery has been inserted into the portable electronic device and transmitting a detection signal to a controller if the main battery is detected;

coupling a voltage from the main battery to a power converter after the main battery has been detected;

providing an operating voltage to a controller, the operating voltage being provided from the power converter after the power converter receives the voltage;

charging a backup battery utilizing a signal transmitted from the controller;

monitoring a battery level of the backup battery to determine if the backup battery has reached a charging level; and

disabling the charging of the backup battery if the charging level of the backup battery has been exceeded.

9. The method of claim 8, further including monitoring a battery level of the main battery to determine if the main battery has been drained below a main battery low threshold voltage.

10. The method of claim 9, further including transmitting a disconnection signal to disconnect the main battery from coupling the voltage to the power converter if the main battery has been drained below the main battery low threshold voltage.

11. The method of claim 10, further including transmitting a connection signal to connect the backup battery to provide power to the power converter if the main battery has been drained below the threshold main battery level.

12. The method of claim 11, wherein a capacitor is coupled between the main battery and the power converter, the capacitor receives the voltage from the main battery, and provides the voltage to the power converter.

13. The method of claim 11, further including monitoring the portable electronic device to determine if a sufficiently charged main battery has been inserted into the portable electronic device and transmitting a detection signal to the controller if the sufficiently charged main battery has been installed.

14. The method of claim 12, further including transmitting a main battery connection signal to connect the main battery if the sufficiently charged main battery has been inserted into the portable electronic device and transmitting a backup battery connection signal to disconnect the backup battery from providing power to the power converter.

15. The method of claim 14, further including the controller checking a level of the backup battery to determine a charging level of the backup battery and to charge the backup battery if the charging level is below an acceptable threshold.

16. The method of claim 8, wherein the portable electronic device is an insulin pump.

17. A program code storage device, comprising:

program code storage device; and

machine-readable program, stored on the program code storage device, the machine-readable program code having instructions, which when executed, cause a controller to;

receive a battery detect signal from a main battery;

receive a main battery voltage reading;

compare the main battery voltage reading against a main battery low voltage threshold;

transmit a main battery disconnect signal to a switching device to disconnect the main battery from providing power to the controller; and

transmit a backup battery connect signal to a switching device to connect the backup battery to provide power to the controller.

18. The program code storage device of claim 17, including instructions, which when executed, cause the controller to transmit a message to a display of a portable electronic device indicating a minimum time for which the backup battery can provide power for the portable electronic device.

19. The program code storage device of claim 17, including instructions, which when executed, transmit a request for the main battery voltage reading to a main battery detection circuit if the battery detect signal is received.

20. A program code storage device, comprising:

program code storage media, machine-readable program code, stored on the program code storage media, the machine-readable program code including instructions, which when executed cause a controller to;

receive a battery detection signal indicating that the main battery is present within a powering circuit of portable electronic device;

receive an operating level of a backup battery;

transmit a signal to a backup battery charging circuit to charge a backup battery if the operating level is below a backup battery charging threshold;

receive a charging level of the backup battery; and

stop transmitting the signal to charging mechanism if the charging level of the backup battery is above the charging threshold.

21. The program code storage device of claim 20, including instructions, which when executed cause the controller to receive a main battery voltage reading and compare the main battery voltage reading against a main battery threshold voltage.

22. The program code storage device of claim 21, including instructions, which when executed cause the controller to transmit a main battery disconnect signal to cause the main battery to cease providing power to the microcontroller and to transmit a backup battery connect signal to cause the backup battery to provide power to the microcontroller.

23. A powering subassembly for a portable electronic device, comprising:

a main battery to provide a main voltage;

a converter to receive the main voltage and to increase the main voltage to at least one operating voltage;

a backup battery to provide a backup voltage; and

a controller to receive the operating voltage from the converter, to monitor a voltage level of the main battery, to compare the monitored voltage level of the main battery to a main battery low voltage threshold, to transmit a disconnect signal to prevent the main battery from providing the main voltage to the converter if the monitored voltage level is less than or equal to the main battery low voltage threshold, and to transmit a connection signal to the backup battery to cause the backup battery to provide a backup voltage to the converter for a predetermined amount of time.

24. The powering subassembly according to claim 23, further including a switching device to uncouple the main battery from a reference ground after receiving the disconnect signal.

25. The powering subassembly according to claim 23, wherein a capacitor is coupled between the main battery and the converter, the capacitor is charged up by the main battery and the capacitor provides a smoother main voltage to the converter.

26. The powering subassembly according to claim 23, wherein the controller receives an operating level of the backup battery and transmits a signal to a charging device to charge a backup battery if the operating level of the backup battery is below a charging threshold.

27. The powering subassembly according to claim 26, wherein the controller monitors a charging level of the backup battery and discontinues transmission of the signal to the charging device if the charging level of the backup battery is above the charging threshold.

28. The powering subassembly of claim 23, wherein the main battery low voltage threshold is less than 1.0 volts.

29. The power subassembly of claim 23, wherein the main battery low voltage threshold is less than 0.8 volts.

30. The powering subassembly of claim 23, wherein rechargeable, lithium, or alkaline batteries can be utilized by the portable electronic device.

31. The powering subassembly according to claim 23, wherein at least 95% of the main battery energy is utilized before the main battery reaches a low voltage threshold.

32. The powering subassembly according to claim 23, wherein the converter provides other operating voltages to a pump, a display, and a second processor, the second processor not being the controller.

33. The powering subassembly according to claim 23, wherein the portable electronic device is an insulin pump.

34. A portable electronic device, comprising:

a display to provide messages to a user; and

a powering subassembly, the power subassembly including;

a main battery to provide a main voltage;

a backup battery to provide a backup voltage;

a capacitor, coupled to one of the main battery or the backup battery, and capable of being coupled to both the main battery and the backup battery, to receive either the main voltage or the backup voltage, and to transfer the received voltage;

a converter to receive the received voltage from the capacitor and to generate at least one operating voltage; and

a controller to receive the at least one operating voltage from the converter, to monitor the main voltage of the main battery, to compare the monitored level of the main battery to a main battery low voltage threshold, and to transmit a disconnect signal to prevent the main voltage from the main battery from being coupled to the capacitor if the monitored level of the main battery is less than or equal to the main battery low voltage threshold.

35. The portable electronic device of claim 34, wherein the controller further transmits a connect signal to couple the backup voltage from the backup battery to the capacitor if the monitored level of the main battery is less than or equal to the main battery low voltage threshold.

36. The portable electronic device of claim 35, wherein the converter provides an operating voltage for the display.

37. The portable electronic device of claim 35, wherein the main battery can be a removable rechargeable battery which can be recharged by household current.

38. The portable electronic device of claim 34, wherein the main battery low voltage threshold is less than 1.0 volts.

39. The portable electronic device of claim 34, wherein the main battery low voltage threshold is less than 0.8 volts.

40. The portable electronic device of claim 34, wherein at least 95% of the main battery energy is utilized before the main battery reaches a low voltage threshold.

41. The portable electronic device of claim 34, wherein the portable electronic device is an insulin pump.