Granted Patent B2

US 8,247,999 · App. 12/009,851 · Granted Aug 21, 2012

Abstract

Claims (40)

1. An apparatus for driving a plurality of electronic loads, comprising:

a DC-to-DC voltage converter having a variable voltage output; and

a controller, the controller being configured to:

select one or more of the plurality of electronic loads and a corresponding output voltage level of the variable voltage output; and

apply a plurality of voltage levels from the variable voltage output across the plurality of electronic loads in accordance with the correspondence and a time division multiplexed scheme;

wherein the correspondence is established prior to the selection, and

wherein the selection of one or more of the plurality of electronic loads is done by effecting a shunt across the unselected one or more of the plurality of electronic loads.

2. The apparatus of claim 1 , wherein the shunt is realizable using a plurality of shunt circuit paths, each shunt circuit path connecting between the outputs of a corresponding one of the electronic loads and having a switch there along.

3. The apparatus of claim 2 , wherein the shunt circuit paths are electrically connected in series.

4. The apparatus of claim 1 , wherein the variable voltage output further comprises circuit paths connected in parallel, each circuit path having the outputs of a corresponding one of the electronic loads there along and having a controllable switch there along.

5. The apparatus of claim 1 , wherein the electronic loads comprise a first load operable at a first voltage and a second load operable at a different second voltage.

6. The apparatus of claim 5 , wherein some of the electronic loads are light emitting diodes, each light source being configured to emit light of a different color.

7. The apparatus of claim 1 , wherein the controller is further configured to shunt all of the plurality of electronic loads during certain times according to the time division multiplexed scheme.

8. An apparatus for driving a plurality of electronic loads, comprising:

a DC-to-DC voltage converter having a variable voltage output, the plurality of electronic loads being connected to share the DC-to-DC voltage converter over a plurality of circuit paths;

a controller, the controller being configured to:

select one or more of the plurality of electronic loads and a corresponding output voltage level of the variable voltage output;

apply a plurality of voltage levels from the variable voltage output across the plurality of electronic loads in accordance with the correspondence and a time division multiplexed scheme; and

effect a shunt across all of the plurality of electronic loads during certain times according to the time division multiplexed scheme;

wherein the correspondence is established prior to the selection;

wherein the loads are either connected across corresponding ones of the circuit paths or are part of corresponding ones of the circuit paths; and

wherein each path includes a switch there along and the controller is connected to operate the switches.

9. The apparatus of claim 8 , wherein the controller is configured to open only one of the switches at a time during driving of the loads.

10. The apparatus of claim 8 , wherein each circuit path is a shunt path for the corresponding one of the electronic loads, and the circuit paths are electrically connected in series.

11. The apparatus of claim 8 , wherein the circuit paths are electrically connected in parallel and the loads are part of corresponding ones of the circuit paths.

12. The apparatus of claim 8 , wherein the DC-to-DC voltage converter is one of a boost DC-to-DC voltage converter, a buck DC-to-DC voltage converter, a buck-boost DC-to-DC voltage converter, and a CUK DC-to-DC voltage converter.

13. The apparatus of claim 8 , wherein the electronic loads comprise a first load operable at a first voltage and a second load operable at a different second voltage.

14. The apparatus of claim 8 , wherein the DC-to-DC voltage converter is configured to apply a first voltage across a first of the loads and to apply a different second voltage across a second of the loads.

15. A method of driving a plurality of electronic loads, comprising:

selecting, by a controller, one or more of the plurality of electronic loads and a corresponding output voltage level of a DC-to-DC voltage converter having a variable voltage output; and

operating, by the DC-to-DC voltage converter in combination with the controller, a plurality of voltage levels from the variable voltage output across the plurality of electronic loads in accordance with the correspondence and a time division multiplexed scheme;

wherein the correspondence is established prior to the selection, and

wherein the selecting of one or more of the plurality of electronic loads is done by effecting a shunt across the unselected one or more of the plurality of electronic loads.

16. The method of claim 15 , wherein the operating includes having the DC-to-DC voltage converter apply a first voltage across one of the electronic components and a different second voltage across another of the electronic components.

17. The method of claim 15 , wherein the operating includes simultaneously closing a circuit path with one of the electronic components and opening one or more circuit paths with any other of electronic components when the DC-to-DC voltage converter is applying a voltage to the one of the electronic components, the circuit paths being connected in parallel.

18. The method of claim 15 , further comprising:

effecting a shunt across all of the plurality of electronic components during certain times according to the time division multiplexed scheme;

then, discharging a capacitor during the certain times; and

then, repeating the operating step;

wherein charges on the capacitor drive the electronic components.

Assignments (9)