LED retrofit driver circuit and method of operating the same

Patent metadata

Field	Value
Publication number	US-10299331-B2
Application number	US-201214117047-A
Country	US
Kind code	B2
Filing date	May 14, 2012
Priority date	May 18, 2011
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A LED retrofit driver circuit ( 3 ) is provided, comprising at least an input ( 6 ) for receiving an operating voltage from a power supply ( 2 ), an output ( 8 ) for connection to one or more LED units ( 5 ), a power converter ( 7 ) connected with said input ( 6 ) and said output ( 8 ) and configured to provide a lamp current ( 50 ) at said output ( 8 ) during operation in at least a first and a second operating state. To provide a versatile circuit ( 3 ), allowing operation with a variety of power supplies and under various load conditions, in said first operating state, the power converter ( 7 ) is adapted to switch between a high current generating mode ( 40 ), in which the power converter ( 7 ) is configured to draw current pulses from said power supply ( 2 ) to provide a first average input current ( 33 a ), and an OFF mode ( 42 ) in which no current is drawn from said power supply ( 2 ). In said second operating state, said power converter ( 7 ) is adapted at least to operate in a low current generating mode ( 41 ), in which the power converter ( 7 ) is configured to draw a current from said power supply ( 2 ) to provide a second average input current ( 33 b ) which is lower than said first average input current ( 33 a ).

First claim

The invention claimed is:

1. An LED retrofit driver circuit comprising:
an input for receiving an operating voltage from a power supply;
an output for connection to one or more LED units;
a power converter connected with said input and said output and configured to provide a lamp current at said output, wherein the power converter is configured to operate in at least a first operating state,
in said first operating state, the power converter being configured to switch between:
a high current generating mode, in which the power converter is configured to draw current pulses from said power supply to draw a first average input current, and
an OFF mode during which no current is drawn from said power supply, wherein the power converter is configured to operate in at least a second operating state, and

in said second operating state, said power converter being configured at least to operate in
a low current generating mode, in which the power converter is configured to draw current pulses from said power supply to draw a second average input current, the second average input current being lower than said first average input current.

2. The LED retrofit driver circuit according to claim 1 , wherein said power converter is configured to alternate between a high current level and a low input current level to draw said first and second average input current.

3. The LED retrofit driver circuit according to claim 1 , wherein said power converter comprises a step-up converter to provide said lamp current from said operating voltage.

4. The LED retrofit driver circuit according to claim 1 , wherein in said second operating state, the power converter is further configured to switch between said low current generating mode and said high current generating mode.

5. The LED retrofit driver circuit according to claim 1 , wherein said power converter is adapted to switch between said high current generating mode, said low current generating mode and said OFF mode in synchronization with said operating voltage.

6. The LED retrofit driver circuit according to claim 1 , further comprising a feedback circuit connected with said power converter and configured to determine at least one electrical parameter at said output to set the mode of said power converter in dependence on said determined parameter.

7. The LED retrofit driver circuit according to claim 6 , wherein said feedback circuit is adapted to set said mode of said power converter so that the lamp current corresponds to a predefined average lamp current.

8. The LED retrofit driver circuit according to claim 6 , wherein said feedback circuit is configured to switch said power converter from said high current generating mode to said low current generating mode and said OFF mode, when said determined electrical parameter corresponds to a maximum threshold value.

9. The LED retrofit driver circuit according to claim 8 , wherein said feedback circuit is configured to switch said power converter from said low current generating mode and/or said OFF mode to said high current generating mode, when said determined electrical parameter corresponds to a minimum threshold value.

10. The LED retrofit driver circuit according to claim 9 , wherein an averaging circuit is provided, connected with said feedback circuit to set at least one of said maximum and minimum threshold value.

11. An LED retrofit lamp comprising at least a LED retrofit driver circuit according to claim 1 and one or more LED units connected with said LED retrofit driver circuit.

12. An LED lighting system comprising a LED retrofit lamp according to claim 11 and a power supply connected to said input of said driver circuit and having a minimum current requirement lower than said second average input current, so that, during operation, said power converter is switched between said low current generating mode and said high current generating mode.

13. A method of operating an LED retrofit driver circuit, said driver circuit comprising an input for receiving an operating voltage from a power supply, an output for connection to one or more LED units and a power converter connected with said input and said output and configured to provide a lamp current at said output during operation,
in a first operating state, the power converter is switched between a high current generating mode, in which current pulses are drawn from said power supply to draw a first average input current, and an OFF mode in which no current is drawn from said power supply,
wherein in a second operating state, the power converter operates in a low current generating mode in which a current is drawn from said power supply to draw a second average input current lower than said first average input current.

Assignees

• Tousain Robertus Leonardus
• Eddeane Redouane
• Claessens Dennis Johannes Antonius
• Vael Philip Louis Zulma
• Jiang Jack
• Signify Holding Bv

Inventors

• Tousain Robertus Leonardus
• Eddeane Redouane
• Claessens Dennis Johannes Antonius
• Vael Philip Louis Zulma
• Jiang Jack

Classifications

• H05B39/044

  continuously (H05B39/042 takes precedence) · CPC title

• F21K9/23

  Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings · CPC title

• H05B33/0845 Primary

  Electricity · mapped topic

• H05B47/17 Primary

  Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations · CPC title

• H05B44/00

  Circuit arrangements for operating electroluminescent light sources (for operating light emitting diodes H05B45/00) · CPC title