Systems and methods for bleeder control related to lighting emitting diodes
View Patent ↗System and method for controlling one or more light emitting diodes. For example, the system includes a bleeder configured to receive a rectified voltage generated by a rectifying bridge, and a dimmer detector configured to receive an input voltage generated by a voltage divider, determine whether or not the rectified voltage is associated with a TRIAC dimmer, and output a control signal to the bleeder. The voltage divider is configured to receive the rectified voltage, and the input voltage indicates a magnitude of the rectified voltage.
1. A system for controlling one or more light emitting diodes, the system comprising:
a dimmer detector configured to:
determine that a rectified voltage is associated with a TRIAC dimmer if a first time duration for the rectified voltage to increase from a first voltage to a second voltage is smaller than a first predetermined duration or a second time duration for the rectified voltage to decrease from the second voltage to the first voltage is smaller than a second predetermined duration;
generate a control signal to turn on a bleeder if the rectified voltage is determined to be associated with a TRIAC dimmer so that the bleeder generates a current, the current being larger than zero in magnitude; and
generate the control signal to turn off the bleeder if the rectified voltage is determined not to be associated with any TRIAC dimmer so that the bleeder does not generate the current.
2. The system of claim 1 wherein:
the dimmer detector is further configured to determine that the rectified voltage is associated with a TRIAC dimmer;
the first time duration is larger than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
3. The system of claim 1 wherein:
the dimmer detector is further configured to determine that the rectified voltage is associated with a TRIAC dimmer;
the first time duration is smaller than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
4. The system of claim 1 wherein the dimmer detector is further configured to determine whether or not the first time duration for the rectified voltage to increase from the first voltage to the second voltage is smaller than the first predetermined duration based at least in part on a change of an input voltage.
5. A method for controlling one or more light emitting diodes, the method comprising:
determining that a rectified voltage is associated with a TRIAC dimmer if a first time duration for the rectified voltage to increase from a first voltage to a second voltage is smaller than a first predetermined duration or a second time duration for the rectified voltage to decrease from the second voltage to the first voltage is smaller than a second predetermined duration;
generating a control signal to turn on a bleeder if the rectified voltage is determined to be associated with a TRIAC dimmer so that the bleeder generates a current, the current being larger than zero in magnitude; and
generating the control signal to turn off the bleeder if the rectified voltage is determined not to be associated with any TRIAC dimmer so that the bleeder does not generate the current.
6. The method of claim 5 further comprising:
determining that the rectified voltage is associated with a TRIAC dimmer;
wherein:
the first time duration is larger than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
7. The method of claim 5 further comprising:
determining that the rectified voltage is associated with a TRIAC dimmer;
wherein:
the first time duration is smaller than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
8. The method of claim 5 wherein determining that the first time duration for the rectified voltage to increase from the first voltage to the second voltage is smaller than the first predetermined duration is based at least in part on a first change of an input voltage.
9. The method of claim 8 wherein determining that the second time duration for the rectified voltage to decrease from the second voltage to the first voltage is smaller than the second predetermined duration is based at least in part on a second change of the input voltage.
10. A system for controlling one or more light emitting diodes, the system comprising:
a dimmer detector configured to:
determine that a rectified voltage is associated with a TRIAC dimmer if a first time duration for an absolute value of a voltage to increase from a first voltage to a second voltage is smaller than a first predetermined duration or a second time duration for the absolute value of the voltage to decrease from the second voltage to the first voltage is smaller than a second predetermined duration;
generate a control signal to turn on a bleeder if the rectified voltage is determined to be associated with a TRIAC dimmer so that the bleeder generates a current, the current being larger than zero in magnitude; and
generate the control signal to turn off the bleeder if the rectified voltage is determined not to be associated with any TRIAC dimmer so that the bleeder does not generate the current.
11. The system of claim 10 wherein:
the dimmer detector is further configured to determine that the rectified voltage is associated with a TRIAC dimmer;
the first time duration is larger than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
12. The system of claim 10 wherein:
the dimmer detector is further configured to determine that the rectified voltage is associated with a TRIAC dimmer;
the first time duration is smaller than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
13. The system of claim 10 wherein the dimmer detector is further configured to determine whether or not the first time duration for the absolute value of the voltage to increase from the first voltage to the second voltage is smaller than the first predetermined duration based at least in part on a change of an input voltage.
14. A method for controlling one or more light emitting diodes, the method comprising:
determining that a rectified voltage is associated with a TRIAC dimmer if a first time duration for an absolute value of a voltage to increase from a first voltage to a second voltage is smaller than a first predetermined duration or a second time duration for the absolute value of the voltage to decrease from the second voltage to the first voltage is smaller than a second predetermined duration;
generating a control signal to turn on a bleeder if the rectified voltage is determined to be associated with a TRIAC dimmer so that the bleeder generates a current, the current being larger than zero in magnitude; and
generating the control signal to turn off the bleeder if the rectified voltage is determined not to be associated with any TRIAC dimmer so that the bleeder does not generate the current.
15. The method of claim 14 further comprising:
determining that the rectified voltage is associated with a TRIAC dimmer;
wherein:
the first time duration is larger than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
16. The method of claim 14 further comprising:
determining that the rectified voltage is associated with a TRIAC dimmer;
wherein:
the first time duration is smaller than the first predetermined duration; and
the second time duration is smaller than the second predetermined duration.
17. The method of claim 14 wherein determining that the first time duration for the absolute value of the voltage to increase from the first voltage to the second voltage is smaller than the first predetermined duration is based at least in part on a first change of an input voltage.
18. The method of claim 17 wherein determining that the second time duration for the absolute value of the voltage to decrease from the second voltage to the first voltage is smaller than the second predetermined duration is based at least in part on a second change of the input voltage.