ADAPTIVE OVERVOLTAGE PROTECTION FOR MULTIFUNCTION LED CHAIN

• US 20170347412A1
• Filed: 05/31/2016
• Published: 11/30/2017
• Est. Priority Date: 05/31/2016
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Milanesi, Paolo, Penzo, Roberto, Galvano, Maurizio, Fragiacomo, Fabio
• Granted Patent: US 10,111,299 B2
• Time in Patent Office: Days
• CPC Class Codes: H05B 45/44 with an active control inside an LED matrix
• CPC Class Codes: H05B 45/50 responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

In one example, a method includes determining, by a device of a system, a voltage feedback value that represents a voltage level of a power signal being provided to a plurality of load elements that are selectively active. In this example, the method also includes adjusting, by the device and based on a quantity of load elements of the plurality of load elements that are active, the voltage level of the power signal such that the voltage feedback value remains less than or equal to an overvoltage threshold.

Claims

1. A method comprising:

determining, by a device of a system, a voltage feedback value that represents a voltage level of a power signal being provided to a plurality of load elements that are selectively active; and

adjusting, by the device and based on a quantity of load elements of the plurality of load elements that are active, the voltage level of the power signal such that the voltage feedback value remains less than or equal to an overvoltage threshold.

2. The method of claim 1, further comprising:

determining the overvoltage threshold based on the quantity of load elements of the plurality of load elements that are active.

3. The method of claim 1, further comprising:

scaling the voltage feedback value based on the quantity of load elements of the plurality of load elements that are active.

4. The method of claim 3, wherein scaling the voltage feedback value comprises:

scaling, by one or more components of the system that are external to the device, the voltage feedback value based on the quantity of load elements of the plurality of load elements that are active.

5. The method of claim 4, wherein the one or more components comprise:

a plurality of resistors selectively included in resistor ladder; and

one or more switches configured to adjust a quantity of resistors of the plurality of resistors included in the resistor ladder based on the quantity of load elements of the plurality of load elements that are active.

6. The method of claim 1, wherein the system includes an output capacitor configured to filter the power signal.

7. The method of claim 1, wherein the plurality of load elements comprises a plurality of light emitting diodes (LEDs).

8. A system comprising a driver device configured to:

determine a voltage feedback value that represents a voltage level of a power signal being provided to a plurality of load elements that are selectively active; and

adjust, based on a quantity of load elements of the plurality of load elements that are active, the voltage level of the power signal such that the voltage feedback value remains less than or equal to an overvoltage threshold.

9. The system of claim 8, wherein the driver device is further configured to:

determine the overvoltage threshold based on the quantity of load elements of the plurality of load elements that are active.

10. The system of claim 8, wherein the driver device is further configured to:

scale the voltage feedback value based on the quantity of load elements of the plurality of load elements that are active.

11. The system of claim 10, further comprising one or more components external to the driver device that are configured to:

scale the voltage feedback value based on the quantity of load elements of the plurality of load elements that are active.

12. The system of claim 11, wherein the one or more components comprise:

a plurality of resistors selectively included in resistor ladder; and

one or more switches configured to adjust a quantity of resistors of the plurality of resistors included in the resistor ladder based on the quantity of load elements of the plurality of load elements that are active.

13. The system of claim 8, further comprising:

an output capacitor configured to filter the power signal.

14. The system of claim 8, wherein the plurality of load elements comprises a plurality of light emitting diodes (LEDs).

15. A system comprising a driver device, the driver device comprising:

means for determining a voltage feedback value that represents a voltage level of a power signal being provided to a plurality of load elements that are selectively active; and

means for adjusting, based on a quantity of load elements of the plurality of load elements that are active, the voltage level of the power signal such that the voltage feedback value remains less than or equal to an overvoltage threshold.

16. The system of claim 15, wherein the driver device further comprises:

means for determining the overvoltage threshold based on the quantity of load elements of the plurality of load elements that are active.

17. The system of claim 15, further comprising:

means for scaling the voltage feedback value based on the quantity of load elements of the plurality of load elements that are active.

18. The system of claim 17, wherein the means for scaling the voltage feedback value are external to the driver device.

19. The system of claim 15, wherein the system includes an output capacitor configured to filter the power signal.

20. The system of claim 15, wherein the plurality of load elements comprises a plurality of light emitting diodes (LEDs).