Power supply that uses a supercapacitive device

• US 7,969,121 B2
• Filed: 02/02/2006
• Issued: 06/28/2011
• Est. Priority Date: 02/02/2005
• Status: Active Grant

• Current Assignee: Cap-Xx Ltd.
• Original Assignee: Cap-Xx Ltd.
• Inventors: Smith, Trevor, Mars, Pierre
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US11/795,916
• Publication Number:
  US 20080129219A1
• Time in Patent Office: 1,972 Days
• Field of Search: 320/107, 320/114, 320/115, 320/166, 320/167
• US Class Current: 320/167
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

A power supply (1) for powering a load, the load being in the form of a flash driver circuit (4) for a digital camera (not shown). The power supply includes a supercapacitive device, in the form of a supercapacitor (8), for powering circuit (4). A regulator unit, in the form of an inductive regulator (10), charges supercapacitor (8).

Claims

1. A power supply for a cellular telephone having a first load and an LED flash, the power supply including:

an input for connecting to a power source;

a first output for connecting to the first load;

a second output for connecting to the LED flash;

a supercapacitive device that is connected to the second output for powering the LED flash; and

a regulator unit connected to the input for charging the supercapacitive device.

2. A power supply according to claim 1 wherein the regulator is in series with the power source, and together these are in parallel with the supercapacitive device.

3. A power supply according to claim 1 wherein the supercapacitive device is in series with the input such that the supercapacitive device and the power source are together in parallel with the LED flash.

4. A power supply according to claim 1 that is operable in a plurality of modes including:

a charging mode for charging the supercapacitive device; and

a discharging for discharging the supercapacitive device to power the LED flash.

5. A power supply according to claim 4 wherein the charging and discharging modes operate simultaneously.

6. A power supply according to claim 4 wherein the charging and discharging mode modes selectively operate mutually exclusively.

7. A power supply according to claim 4 wherein the first load is powered irrespective of whether the power supply is in the charging or discharging mode.

8. A power supply according to claim 1 wherein the regulator unit limits the charging current for the supercapacitor to less than a predetermined value.

9. A power supply according to claim 8 wherein the predetermined value is about 2 Amps.

10. A power supply according to claim 8 wherein the predetermined value is about 1 Amp.

11. A power supply according to claim 1 that limits the current drawn from the power source to less than a predetermined value.

12. A power supply according to claim 11 wherein the predetermined value is about 2 Amps.

13. A power supply according to claim 11 wherein the predetermined value is about 1 Amp.

14. A power supply according to claim 1 wherein the first output defines the second output.

15. A power supply according to claim 1 wherein the first output selectively defines the second output.

16. A power supply according to claim 1 wherein the first load is a communications module.

17. A power supply according to claim 1 wherein the first load is a power amplifier.

18. A power supply for an LED flash, the power supply including:

an input for connecting to a power source that provides an input voltage;

an output for connecting to the LED flash;

a supercapacitive device that is connected to output for powering the LED flash; and

;

a regulator unit that boosts the input voltage, the regulator unit being connected to the input for charging the supercapacitive device.

19. A power supply for a plurality of loads that draw respective load currents I₁, I₂, . . . I_N, where N≧

2, the power supply including;

an input for connecting to a power source that provides a minimum source voltage V_s;

an output for selectively connecting with one or more of the loads for providing the load currents I₁, I₂, . . . I_N at respective predetermined load voltages V₁, V₂, . . . V_N, wherein V₁≠

V₂, and, . . . , and V₁ ≠

V_N;

a supercapacitive device in parallel with the output; and

a control circuit disposed between the input and the output for selectively applying one of V₁, V₂, . . . V_N to the output.

20. A power supply according to claim 19 wherein one or more of V₁, V₂, . . . and V_N≧

V_s.