Actuating a plurality of series-connected luminous elements

1. A circuit for actuating a plurality of light-emitting means which are connected in series,

comprising a plurality of electronic switches, which can be actuated depending on a rectified system voltage,

wherein the plurality of electronic switches are arranged in parallel with at least some of the light-emitting means,

wherein each of the plurality of electronic switches short-circuits on activation of in each case at least one of the light-emitting means connected in series,

with at least one energy store,

which is connected in parallel with a first group of light-emitting means during a charge phase by virtue of the electronic switches, and

which is connected in parallel with a second group of light-emitting means during a discharge phase by virtue of the electronic switches.

2. The circuit as claimed in claim 1 , wherein there is a higher voltage drop across the first group of light-emitting means than across the second group of light-emitting means.

3. The circuit as claimed in claim 1 , wherein the energy store is configured to be charged during an initial charge phase over a plurality of cycles of the rectified system voltage.

4. The circuit as claimed in claim 1 , wherein the energy store is connected in series with a current source.

5. The circuit as claimed in claim 1 , wherein the light-emitting means connected in series are connected in series with a voltage-controlled current source.

6. The circuit as claimed in claim 5 , wherein the voltage-controlled current source is actuable via the rectified system voltage.

7. The circuit as claimed in claim 5 , wherein the electronic switches and the voltage-controlled current source are arranged together in an integrated circuit.

8. The circuit as claimed in claim 1 , comprising a first energy store and a second energy store,

wherein the first energy store

is connected in parallel with the first group of light-emitting means during a charge phase by virtue of the electronic switches, and

is connected in parallel with the second group of light-emitting means during a discharge phase by virtue of the electronic switches,

wherein the second energy store

is connected in parallel with the first group of light-emitting means during a charge phase by virtue of the electronic switches, and

is connected in parallel with a third group of light-emitting means during a discharge phase, wherein the third group of light-emitting means is in particular a subset of the first group of light-emitting means.

9. The circuit as claimed in claim 1 , wherein detection and evaluation of the rectified system voltage is performed using a control unit and, depending on a level of the detected system voltage, more or fewer light-emitting means can be activated via the electronic switches.

10. The circuit as claimed in claim 9 , wherein dimmable actuation of the light-emitting means is performed using the control unit.

11. The circuit as claimed in claim 9 , wherein the control unit and the electronic switches are integrated together in a circuit.

12. The circuit as claimed in claim 1 , wherein the light-emitting means comprises at least one semiconductor light-emitting element.

13. The circuit as claimed in claim 1 , wherein the electronic switches comprise semiconductor switches.

14. The circuit as claimed in claim 1 , wherein the energy store comprises a capacitor, an electrolyte capacitor or a battery.

15. The circuit as claimed in claim 1 , wherein the energy store is connected in series with a constant current source or a voltage-controlled current source.

16. The circuit as claimed in claim 1 , wherein the light-emitting means comprises a group of semiconductor light-emitting elements.

17. The circuit as claimed in claim 1 , wherein the electronic switches comprise bipolar transistors and/or MOSFETs.