Granted Patent B2

US 12,075,532 · App. 17/862,020 · Granted Aug 27, 2024

Inventor: Stuart W. DeJonge (Riegelsville, PA)

Assignee: Lutron Technology Company LLC

H05B45/14H02M3/33507H05B45/327H05B45/382H05B45/39H05B45/10

Abstract

Claims (70)

1. A load control device for controlling an amount of power delivered to a lighting load, the load control device comprising:

a load regulation circuit configured to control a magnitude of a load current conducted through the electrical load, the load regulation circuit comprising:

an inverter circuit; and

a control circuit to:

receive a target intensity;

determine whether the received target intensity is between:

a high-end intensity and a defined threshold intensity between the high-end intensity and a low-end intensity; or

the threshold intensity and the low-end intensity;

for received target intensities between the defined threshold intensity and the high-end intensity:

 cause the inverter to operate in a normal mode in which the inverter circuit transitions between an active state and an inactive state over each of a first plurality of periods, each of the first plurality of periods having a first duration; and

 adjust the active state current supplied by the inverter circuit to deliver a target current to cause the lighting load to produce the received target intensity; and

for received target intensities between the defined threshold intensity and the low-end intensity;

 cause the inverter to operate in a burst mode in which the inverter circuit maintains a constant current; and

 cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods to deliver the target current to cause the lighting load to produce the received target intensity, each of the second plurality periods having a respective duration less than or equal to the first duration.

2. The load control device of claim 1 , wherein to cause the inverter circuit to transition between the active state and the inactive state over the second plurality of periods, the control circuit to further:

cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, each of the second plurality periods having a respective duration.

3. The load control device of claim 2 , wherein to cause the inverter circuit to transition between the active state and the inactive state over the second plurality of periods, the control circuit to further:

cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, each of the second plurality periods having a respective duration that is less than the first duration.

4. The load control device of claim 3 , wherein to cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, each of the second plurality periods having a respective duration that is less than the first duration, the control circuit to further:

cause the inverter circuit to transition between the active state and the inactive state over each of the second plurality of periods, wherein the duration of each period included in at least a portion of the second plurality of periods decreases over successive periods.

5. The load control device of claim 4 , the control circuit to further maintain a constant inverter duty cycle over each of the second plurality of periods.

6. The load control device of claim 5 , wherein the control circuit to further:

determine whether a duration of the active portion of one of the second plurality of periods is less than a defined minimum inverter ON time; and

cease the decrease of the duration of subsequent second periods responsive to the determination, by the control circuitry, that the duration of the active portion of one of the second plurality of periods is less than the defined minimum inverter ON time.

7. The load control device of claim 1 , further comprising:

current sense circuit to provide a signal indicative of a magnitude of the load current to the control circuit.

8. A method of controlling operation of a light-emitting diode (LED) lighting device, the method comprising:

receiving a target intensity by a control circuit included in an LED controller; and

determining, by the control circuit, whether the received target intensity is between:

a high-end intensity and a defined threshold intensity between the high-end intensity and a low-end intensity; or

the defined threshold intensity and the low-end intensity

for target intensities between the defined threshold intensity and the high-end intensity:

causing an inverter circuitry included in an operatively coupled load regulation circuit to operate in a normal mode in which the inverter circuit transitions between an active state and an inactive state over each of a first plurality of periods, each of the first plurality of periods having a first duration; and

causing the load regulation circuit to adjust the active state current supplied to an LED lighting load to cause the LED lighting load to produce the received target intensity; and

for target intensities between the defined threshold intensity the low-end intensity;

causing the inverter circuit to operate in a burst mode in which the inverter circuit transitions between the active state and the inactive state over each of a second plurality of periods, each of the second plurality periods having a respective duration less than or equal to the first duration; and

causing the load regulation circuit to maintain a constant active state current supplied to the LED lighting load sufficient to cause the LED lighting load to produce the received target intensity.

9. The method of claim 8 , wherein causing the inverter circuit to operate in the burst mode in which the inverter circuit transitions between the active state and the inactive state over each of the second plurality of periods further comprises:

causing, by the control circuit, the inverter circuit to transition between the active state and the inactive state over the second plurality of periods, each of the second plurality periods having a respective duration.

10. The method of claim 9 , wherein causing the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, further comprises:

causing, by the control circuit, the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, wherein a respective duration of each of the second plurality periods is less than the first duration.

11. The method of claim 10 , wherein causing the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, further comprises:

causing, by the control circuit, the inverter circuit to transition between the active state and the inactive state over each of the second plurality of periods, wherein the duration of each period included in at least a portion of the second plurality of periods decreases over successive periods.

12. The method of claim 11 , further comprising:

maintaining, by the control circuit, a constant inverter duty cycle over each of the second plurality of periods.

13. The method of claim 12 , further comprising:

determining, by the control circuit, whether a duration of the active portion of one of the second plurality of periods is less than a defined minimum inverter ON time; and

cease decreasing the duration of subsequent second periods responsive to the determination, by the control circuitry, that the duration of the active portion of one of the second plurality of periods is less than the defined minimum inverter ON time.

14. A non-transitory, machine-readable, storage device that includes instructions that, when executed by control circuitry disposed in a light-emitting diode (LED) controller couplable to an LED lighting device, cause the control circuitry to:

receive a target intensity; and

determine whether the received target intensity is between:

a high-end intensity and a defined threshold intensity between the high-end intensity and a low-end intensity: or

the defined threshold intensity and the low-end intensity;

for target intensities between the defined threshold intensity and the high-end intensity:

cause inverter circuitry included in an operatively coupled load regulation circuit to operate in a normal mode in which the inverter circuit transitions between an active state and an inactive state over each of a first plurality of periods, each of the first plurality of periods having a first duration; and

cause the load regulation circuit to adjust the active state current supplied to an LED lighting load to cause the LED lighting load to produce the received target intensity; and

for target intensities between the defined threshold intensity the low-end intensity;

cause the inverter circuit to operate in a burst mode in which the inverter circuit transitions between the active state and the inactive state over each of a second plurality of periods, each of the second plurality periods having a respective duration less than or equal to the first duration; and

cause the load regulation circuit to maintain a constant active state current supplied to the LED lighting load sufficient to cause the LED lighting load to produce the received target intensity.

15. The non-transitory, machine-readable, storage device of claim 14 , wherein the instructions that cause the control circuit to cause the inverter circuit to operate in the burst mode in which the inverter circuit transitions between the active state and the inactive state over each of the second plurality of periods further cause the control circuit to:

causing, by the control circuit, the inverter circuit to transition between the active state and the inactive state over the second plurality of periods, each of the second plurality periods having a respective duration.

16. The non-transitory, machine-readable, storage device of claim 15 , wherein the instructions that cause the control circuit to cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, further cause the control circuit to:

cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, wherein a respective duration of each of the second plurality periods is less than the first duration.

17. The non-transitory, machine-readable, storage device of claim 16 , wherein the instructions that cause the control circuit to cause the inverter circuit to transition between the active state and the inactive state over a second plurality of periods, further cause the control circuit to:

cause the inverter circuit to transition between the active state and the inactive state over each of the second plurality of periods, wherein the duration of each period included in at least a portion of the second plurality of periods decreases over successive periods.

18. The non-transitory, machine-readable, storage device of claim 17 , wherein the instructions, when executed by the control circuit, further cause the control circuit to:

maintain a constant inverter duty cycle over each of the second plurality of periods.

19. The non-transitory, machine-readable, storage device of claim 18 , wherein the instructions, when executed by the control circuit, further cause the control circuit to:

determine whether a duration of the active portion of one of the second plurality of periods is less than a defined minimum inverter ON time; and

cease the decrease of the duration of subsequent second periods responsive to the determination that the duration of the active portion of one of the second plurality of periods is less than the defined minimum inverter ON time.

Continuity (8)