Power management for a portable electronic device

• US 7,649,344 B2
• Filed: 07/31/2003
• Issued: 01/19/2010
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Bang, William R., La Rosa, Dean
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): Boateng; Alexis
• Application Number:
  US10/631,512
• Publication Number:
  US 20040021446A1
• Time in Patent Office: 2,364 Days
• Field of Search: 320/114, 320/103, 320/107, 320/127, 320/167, 320/166, 320/101, 320/117, 320/112, 320/121, 320/109, 323/266, 323/268, 307/66, 307/43, 307/103, 307/109, 307/150, 307/64, 307/86, 307/110, 363/49, 363/16, 363/17, 363/50
• US Class Current: 320/167
• 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 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H04B 1/3883 Arrangements for mounting batteries or battery chargers
• CPC Class Codes: H04B 2215/063 by smoothing the transmission power envelope

Abstract

A system for a supplemental power source for a hand held portable electronic device is provided. A super capacitor is connected in parallel to a main battery of the portable electronic device. When the main battery becomes disconnected, the super capacitor is used to power the portable electronic device. The super capacitor is also used to provide compensation for the internal impedance of the main battery and the path impedance between the main battery and the load.

Claims

1. A system that provides impedance compensation for a battery comprising:

a battery connected to provide primary power directly to a first load component of a hand held terminal;

a super capacitor connected electrically in parallel with the battery, the super capacitor providing internal impedance compensation to the battery and, upon the hand held terminal being dropped and the battery resultantly being disconnected from the first load component, automatically acts as a secondary power source to the first load component; and

a regulator connected electrically to the super capacitor and battery for providing power to a second load component of the hand held terminal.

2. The system of claim 1, wherein the super capacitor is employed to prevent a voltage dropout in the system.

3. The system of claim 1, further comprising an inrush current limiter to prevent a current surge in the system.

4. The system of claim 1, further comprising an inrush current limiter electrically in series with the super capacitor.

5. The system of claim 1, wherein the battery is rechargeable.

6. The system of claim 5, wherein the battery comprises a technology that is one of lithium-ion, nickel-cadmium, alkaline, and nickel-metal-hydride.

7. The system of claim 1, wherein the super capacitor further provides compensation for path impedance between the battery and the first and second terminal loads.

8. The system of claim 1, wherein the super capacitor provides impedance compensation for the battery in a portable electronic device.

9. The system of claim 1, wherein the super capacitor compensates for at least one of a change in charge of the battery and a change in battery temperature.

10. The system of claim 1, wherein the super capacitor provides the compensation to prevent premature dropout of the regulator.

25. The system of claim 1, wherein the first and second load components are radios.

26. The system of claim 1, wherein one of the first and second load components is a barcode scanner.

27. The system of claim 1, wherein one of the first and second load components is a magnetic stripe reader.

28. The system of claim 1, wherein the hand-held terminal comprises a touch panel.

11. A system that provides impedance compensation for a battery in a portable electronic device, comprising:

a main battery that provides power directly to a first load component of the portable electronic device through battery contacts;

a super capacitor connected electrically in parallel with the battery, the super capacitor providing internal impedance compensation to the battery and, when the terminal is dropped and the battery resultantly disconnected from the first load component, automatically powers the first load component when ability of the battery to provide a suitable level of power to the first load component is diminished due to disconnection there from; and

a regulator that connects the battery and the super capacitor to the portable electronic device and powers the first and second load components.

12. The system of claim 11, wherein the super capacitor is connected at least one of in series with an inrush current limiter to prevent a current surge and in parallel with the battery to provide a supplemental power source.

13. The system of claim 11, wherein the super capacitor has a low internal impedance that compensates for a high internal impedance of the battery.

14. A system that provides impedance compensation for a battery in a portable electronic device, comprising:

a battery that provides main power to a regulator and a first load component of a portable electronic device through battery contacts, the regulator providing power to a second load component of the device;

a super capacitor connected directly to the regulator such that it maintains electrical contact with the portable device even when the device is dropped, the super capacitor provides internal impedance compensation to the battery and, when the terminal is dropped and the battery is resultantly disconnected from the regulator, automatically acts as a supplemental power source for both the first and second load components when the battery is disconnected from the regulator; and

a current limiter to limit the current output of the super capacitor.

15. The system of claim 14, wherein the super capacitor is connected at least one of in series with an inrush current limiter to prevent a current surge and in parallel with the battery to provide a supplemental power source.

16. A system that provides impedance compensation for a battery in a portable electronic device, comprising:

a main battery that provides power directly to a first load component of the portable electronic device through battery contacts;

a super capacitor connected electrically in parallel with the battery, the super capacitor providing internal impedance compensation to the battery and, when the terminal is dropped and the battery resultantly disconnected from the first load component, automatically powers the first load component when ability of the battery to provide a suitable level of power to the first load component is diminished due to disconnection there from; and

a regulator that connects the battery and the super capacitor to the portable electronic device and powers the first and second load components.

17. The system of claim 16, wherein the long-term energy storage component is a battery and the short-term energy storage component is a capacitor.

18. The system of claim 17, wherein the capacitor is a super capacitor.

19. The system of claim 16, wherein the short-term energy storage component provides compensation to internal impedance changes of the long-term energy storage component.

20. The system of claim 16, wherein the short-term energy storage component provides the impedance compensation in a hand-held portable terminal.

21. A method of managing impedance changes of a power source in a portable terminal, comprising:

providing a long-term energy storage component to primarily power a first and second load component associated with a portable terminal;

securely connecting a short-term energy storage component to a regulator of the portable terminal such that the first load component remains unaffected when the portable terminal is dropped;

compensating for change in an internal impedance of the long-term energy storage component by employing the short-term energy storage component;

regulating voltage to the first load component from the short-term storage component and the long-term storage component; and

automatically supplying power to the first and second load component from the short term energy storage component when the long term energy storage component is disconnected from the load.

22. The method of claim 21, wherein the long-term energy storage component is a battery and the short-term energy storage component is a super capacitor.

23. The method of claim 21, wherein the short-term storage component compensates for a change in charge and a change in temperature of the long-term storage component.

24. The method of claim 21, further comprising limiting the current to the short-term storage component.