AC DRIVEN LIGHT-EMITTING DIODES

• US 20120091906A1
• Filed: 12/22/2011
• Published: 04/19/2012
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Wendt, Matthias, DEPPE, Carsten
• Granted Patent: US 8,456,089 B2
• Time in Patent Office: Days
• US Class Current: 315/187
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: H05B 45/42 Antiparallel configurations
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

Disclosed is a lighting device including a circuit including at least two parallel-connected light-emitting diodes of opposite pole in a first parallel branch and comprising at least two parallel-connected light-emitting diodes of opposite pole in a second parallel branch, and also including a capacitor and a coil. At least one of the diodes emits red light, blue light, and/or white light.

Claims

1. A lighting device, comprising:

a first branch including,

a first component comprising at first least a first antiparallel pair of light-emitting diodes,

a second component comprising at least a second antiparallel pair of light-emitting diodes, and

a capacitor,

wherein the first component, the second component, and the capacitor are all arranged in series with each other between a first supply voltage and a second supply voltage; and

a second branch including,

a third component comprising at first least a third antiparallel pair of light-emitting diodes,

a fourth component comprising at least a fourth antiparallel pair of light-emitting diodes, and

a coil,

wherein the third component, the fourth component, and the coil are all arranged in series with each other between the first supply voltage and the second supply voltage,

wherein the first branch is in parallel with the second branch.

2. The lighting device of claim 1, wherein the first parallel branch has a first phase difference Δ

θ

1 between a voltage and a current in the first parallel branch, and wherein the second parallel branch has a second phase difference Δ

θ

2 between a voltage and a current in the second parallel branch, and wherein Δ

θ

2−

Δ

θ

1=90 degrees.

3. The lighting device of claim 1, wherein a light culmination point of one of the two parallel-connected light-emitting diodes of opposite pole in the first parallel branch coincides with a point in time when a first one of the two parallel-connected light-emitting diodes of opposite pole in the second parallel branch switches on and when a second one of the two parallel-connected light-emitting diodes of opposite pole in the second parallel branch switches off.

4. The lighting device of claim 1, wherein at least one of the diodes emits cold white light.

5. The lighting device of claim 1, wherein at least one of the diodes emits warm white light.

6. The lighting device of claim 1, wherein at least one of the diodes emits red light.

7. The lighting device of claim 1, wherein at least one of the diodes emits blue light.

8. A circuit, comprising:

a first parallel branch including,

at least a first antiparallel pair of light-emitting diodes, and

a capacitor in series with the first antiparallel pair of light-emitting diodes;

a second parallel branch including,

at least a second antiparallel pair of light-emitting diodes, and

a coil in series with the second antiparallel pair of light-emitting diodes,

wherein the first branch is in parallel with the second branch,

wherein a light culmination point of one of the first antiparallel pair of light-emitting diodes in the first parallel branch coincides with a point in time when a first one of the second antiparallel pair of light-emitting diodes in the second parallel branch switches on and when a second one of the second antiparallel pair of light-emitting diodes in the second parallel branch switches off

9. The circuit of claim 8, wherein the first parallel branch has a first phase difference Δ

θ

1 between a voltage and a current in the first parallel branch, and wherein the second parallel branch has a second phase difference Δ

θ

2 between a voltage and a current in the second parallel branch, and wherein Δ

θ

2−

Δ

θ

1=90 degrees.

10. A lighting device comprising a transformer and a circuit comprising at least two parallel-connected light-emitting diodes of opposite pole in a first parallel branch and comprising at least two parallel-connected light-emitting diodes of opposite pole in a second parallel branch, and also comprising a capacitor and a coil, wherein the first parallel branch includes the capacitor and the second parallel branch includes the coil.

11. The lighting device of claim 10, wherein at least one of the parallel branches includes two diode chains.

12. The lighting device of claim 10, wherein at least one of the parallel branches includes a series connection of a number of parallel-connected diodes of opposite pole.

13. The lighting device of claim 10, wherein at least one of the diodes emits cold white light.

14. The lighting device of claim 10, wherein at least one of the diodes emits warm white light.

15. The lighting device of claim 10, wherein at least one of the diodes emits red light.

16. The lighting device of claim 10, wherein at least one of the diodes emits blue light.

17. The lighting device as claimed in claim 10, further includes an electronic converter, wherein a secondary frequency of the electronic converter is adjustable.