LOAD CONTROL DEVICE FOR A LIGHT-EMITTING DIODE LIGHT SOURCE
First Claim
1. A load control device for controlling an amount of power delivered to an electrical load, the load control device comprising:
- a load regulation circuit configured to control a magnitude of a load current conducted through the electrical load to control the amount of power delivered to the electrical load; and
a control circuit coupled to the load regulation circuit and configured to adjust an average magnitude of the load current, wherein the control circuit is configured to operate in a normal mode to regulate the average magnitude of the load current to a target load current that ranges from a maximum rated current to a minimum rated current, the control circuit further configured to operate in a burst mode to regulate the average magnitude of the load current below the minimum rated current;
wherein, during the burst mode, the control circuit is configured to regulate a peak magnitude of the load current to the minimum rated current during a first time period using a control loop, and to stop regulating the load current during a second time period resulting in the average magnitude of the load current being below the minimum rated current, the control circuit configured to freeze the control loop during the second time period.
0 Assignments
0 Petitions
Accused Products
Abstract
A load control device for controlling the amount of power delivered to an electrical load is able to operate in a burst mode to adjust the amount of power delivered to the electrical load to low levels. The load control device comprises a control circuit that operates in a normal mode to regulate an average magnitude of a load current conducted through the load to a target load current that ranges from a maximum rated current to a minimum rated current. The control circuit operates in the burst mode to regulate the average magnitude of the load current below the minimum rated current. During the burst mode, the control circuit regulates a peak magnitude of the load current to the minimum rated current during a first time period, and stops regulating the load current during a second time period, such that the average magnitude of the load current is below the minimum rated current.
16 Citations
40 Claims
-
1. A load control device for controlling an amount of power delivered to an electrical load, the load control device comprising:
-
a load regulation circuit configured to control a magnitude of a load current conducted through the electrical load to control the amount of power delivered to the electrical load; and a control circuit coupled to the load regulation circuit and configured to adjust an average magnitude of the load current, wherein the control circuit is configured to operate in a normal mode to regulate the average magnitude of the load current to a target load current that ranges from a maximum rated current to a minimum rated current, the control circuit further configured to operate in a burst mode to regulate the average magnitude of the load current below the minimum rated current; wherein, during the burst mode, the control circuit is configured to regulate a peak magnitude of the load current to the minimum rated current during a first time period using a control loop, and to stop regulating the load current during a second time period resulting in the average magnitude of the load current being below the minimum rated current, the control circuit configured to freeze the control loop during the second time period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. An LED driver for controlling an intensity of an LED light source, the LED driver comprising:
-
an LED drive circuit configured to conduct a load current through the LED light source and to control the intensity of the LED light source; and a control circuit coupled to the LED drive circuit for adjusting an average magnitude of the load current to control the intensity of the LED light source to a target intensity, wherein the control circuit is configured to operate in a normal mode to regulate the average magnitude of the load current to a target load current that ranges from a maximum rated current to a minimum rated current, the control circuit further configured to operate in a burst mode to regulate the average magnitude of the load current below the minimum rated current; wherein, during the burst mode, the control circuit is configured to control the LED drive circuit in an active state during a first time period in which the control circuit regulates a peak magnitude of the load current to the minimum rated current using a control loop, the control circuit further configured to control the LED drive circuit in an inactive state during a second time period in which the control circuit freezes the control loop to stop regulating the load current, such that the average magnitude of the load current is below the minimum rated current. - View Dependent Claims (17, 18, 19, 20)
-
-
21. A load control device for controlling an amount of power delivered to an electrical load, the load control device comprising:
-
a load regulation circuit configured to control a magnitude of a load current conducted through the electrical load to control the amount of power delivered to the electrical load; and a control circuit coupled to the load regulation circuit and configured to adjust an average magnitude of the load current, wherein the control circuit is configured to operate in a normal mode and a burst mode, wherein the burst mode comprises an active state during a first time period of a burst mode period and an inactive state during a second time period of the burst mode period, and a duration of the active state of the burst mode period is determined based on a burst duty cycle; and wherein, during the normal mode, the control circuit is configured to regulate the average magnitude of the load current by holding the burst duty cycle constant and adjusting a target load current, and wherein, during the burst mode, the control circuit is configured to regulate the average magnitude of the load current by adjusting the burst duty cycle and the target load current; and wherein, during the burst mode, the control circuit is configured to adjust the target load current by a current offset that ranges from a minimum current offset to a maximum current offset based on the burst duty cycle and a target amount of power to be delivered to the electrical load. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
-
-
34. A load control device for controlling an amount of power delivered to an electrical load, the load control device comprising:
-
a load regulation circuit configured to control a magnitude of a load current conducted through the electrical load to control the amount of power delivered to the electrical load; and a control circuit coupled to the load regulation circuit and configured to adjust an average magnitude of the load current, wherein the control circuit is configured to operate in a normal mode to regulate the average magnitude of the load current between a maximum rated current to a minimum rated current, the control circuit further configured to operate in a burst mode to regulate the average magnitude of the load current below the minimum rated current; wherein, during the burst mode, the control circuit is configured to regulate a peak magnitude of the load current to a target load current during a first time period, and to stop regulating the load current during a second time period resulting in the average magnitude of the load current being below the minimum rated current, the control circuit configured to increase the magnitude of the load current from an initial current to the target load current over a ramp time period at a beginning of the first time period. - View Dependent Claims (35, 36, 37, 38, 39, 40)
-
Specification