Arrangement for operating radiation emitting devices, method of manufacturing the arrangement and compensation structure
An arrangement for operating radiation emitting devices includes a plurality of radiation emitting devices each having a first capacitance, a driver circuit that supplies the devices with electrical energy, and a compensation structure having a variable second capacitance corresponding to each device and means for adjusting the respective second capacitance, the compensation structure being connected to the device such that a total capacitance assigned to a device and dependent on the first capacitance can be adjusted by the second capacitance.
1. An arrangement for operating radiation emitting devices comprising:
a plurality of radiation emitting devices each having a first capacitance,
a driver circuit that supplies the devices with electrical energy, and
a compensation structure having a variable second capacitance corresponding to each device and configured to adjust the respective second capacitance, the compensation structure being connected to the device such that a total capacitance assigned to a device and dependent on the first capacitance can be adjusted by the second capacitance.
2. The arrangement according to claim 1 , wherein, at least for some of the devices or for each of the devices, the total capacitance is adjustable such that a deviation of the total capacities from a predetermined nominal value is reduced.
3. The arrangement according to claim 1 , wherein
the compensation structure comprises, corresponding to each device, a respective compensation element having the respective variable second capacitance and configured to adjust the respective second capacitance; and
the compensation element connects in parallel with the corresponding device.
4. The arrangement according to claim 3 , wherein
the driver circuit has, corresponding to each device, a respective output that supplies the respective device with a predetermined current and/or with a predetermined voltage, and
the compensation element connects in parallel with the corresponding output of the driver circuit.
5. The arrangement according to claim 1 , wherein the plurality of radiation emitting devices forms a unit with the compensation structure.
6. A method of fabricating an arrangement with radiation emitting devices, the method comprising:
a) providing a plurality of radiation emitting devices, each having a first capacitance,
b) measuring the first capacitance of each device,
c) providing a compensation structure that, corresponding to each device, has a variable second capacitance and is configured to adjust the respective second capacitance, and
d) controlling the compensation structure to adjust the respective second capacitance depending on the respective measured first capacitance such that at least for some of the devices or for each of the devices, a deviation of a total capacitance assigned to the respective device from a setpoint value is reduced.
7. The method according to claim 6 , wherein the compensation structure is controlled such that the respective total capacitance assigned to the devices has a same predetermined value or a substantially same predetermined value for each device.
8. A compensation structure comprising:
a plurality of compensation elements each having a variable capacitance and being configured to adjust the respective capacitance,
a communication interface that receives a control signal that sets the capacitances, and
an input and an output per compensation element that couples the respective capacitance with an external circuit.
9. The compensation structure according to claim 8 , wherein each of the compensation elements comprises at least one first switch and at least one capacitor having a first electrode and a second electrode, wherein per compensation element
the respective first electrode of the at least one capacitor is coupled with the at least one first switch, and
the at least one first switch that couples the respective capacitance of the at least one capacitor to the external circuit couples the respective at least one capacitor to the input and/or output of the respective compensation element as a function of the actuating signal.
10. The compensation structure according to claim 9 , wherein each of the compensation elements comprises at least a second switch, wherein per compensation element
the respective second electrode of the at least one capacitor is coupled to the at least one second switch, and
the at least one second switch that couples the respective capacitance of the at least one capacitor to the external circuit couples the respective at least one capacitor to the input and/or output of the respective compensation element as a function of the actuating signal, wherein the at least one first switch forms a transmission gate with the at least one second switch.
11. The compensation structure according to claim 8 , wherein the compensation elements are arranged in a matrix.
12. The compensation structure according to claim 8 , wherein the compensation elements are digitally adjustable variable capacitors.
13. The compensation structure according to claim 12 , wherein the digitally adjustable variable capacitors each comprise a plurality of metal-insulator-metal capacitors each having first and the second electrodes.
14. The compensation structure according to claim 13 , wherein the metal-insulator-metal capacitors are disposed between the at least one first switch and the at least one second switch, and the first and second electrode of the metal-insulator-metal capacitors each coupled to the at least one first switch and the at least one second switch, respectively, by a via.