Apparatus, Method and System for Providing AC Line Power to Lighting Devices

• US 20120081009A1
• Filed: 10/27/2011
• Published: 04/05/2012
• Est. Priority Date: 06/04/2009
• Status: Active Grant

• Current Assignee: Chemtron Research LLC (Intellectual Ventures LLC)
• Original Assignee: Exclara, Inc. (Million Star Technology Ltd.)
• Inventors: Shteynberg, Anatoly, Zhou, Dongsheng, Dreyer, Stephen F., Ohara, Harlan, Doluca, Sinan
• Granted Patent: US 8,569,956 B2
• Time in Patent Office: Days
• US Class Current: 315/122
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/36 Circuits for reducing or suppressing harmonics, ripples or electromagnetic interferences [EMI]
• CPC Class Codes: H05B 45/44 with an active control inside an LED matrix
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• CPC Class Codes: H05B 45/48 having LEDs organised in strings and incorporating parallel shunting devices
• CPC Class Codes: H05B 45/50 responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
• CPC Class Codes: H05B 45/56 involving measures to prevent abnormal temperature of the LEDs
• CPC Class Codes: H05B 45/59 for reducing or suppressing flicker or glow effects

Abstract

An apparatus, method and system are disclosed for providing AC line power to lighting devices such as light emitting diodes (“LEDs”). An exemplary apparatus comprises: a plurality of LEDs coupled in series to form a plurality of segments of LEDs; first and second current regulators; a current sensor; and a controller to monitor a current level through a series LED current path, and to provide for first or second segments of LEDs to be in or out of the series LED current path at different current levels. A voltage regulator is also utilized to provide a voltage during a zero-crossing interval of the AC voltage. In an exemplary embodiment, first and second segments of LEDs are both in the series LED current path regulated at a lower current level compared to when only the first segment of LEDs is in the series LED current path.

Claims

1. A method of providing power to a plurality of light emitting diodes couplable to receive an AC voltage, the plurality of light emitting diodes coupled in series to form a plurality of segments of light emitting diodes each comprising at least one light emitting diode, the plurality of segments of light emitting diodes coupled to a plurality of current regulators, the method comprising:

monitoring and regulating a current level through a series light emitting diode current path;

providing for a first segment of light emitting diodes to be in or out of the series light emitting diode current path at about a first predetermined current level or until the current level has reached about the first predetermined current level; and

providing for a second segment of light emitting diodes to be in or out of the series light emitting diode current path at about a second predetermined current level or until the current level has reached about the second predetermined current level.

2. The method of claim 1, further comprising:

during a zero crossing interval of the AC voltage, using a voltage regulator, providing a voltage or a current sufficient for at least one light emitting diode to be on and conducting.

3. The method of claim 2, further comprising:

during a peak interval of the AC voltage, charging the voltage regulator.

4. The method of claim 2, wherein the voltage regulator comprises at least one capacitor coupled to a diode.

5. The method of claim 1, further comprising:

regulating the current level of the series light emitting diode current path to be less than or equal to a maximum current level.

6. The method of claim 1, wherein the steps of providing for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

turning off a first current regulator coupled to the first segment of light emitting diodes; and

turning on a second current regulator coupled to the second segment of light emitting diodes or coupled to the first segment of light emitting diodes.

7. The method of claim 6, wherein the first current regulator comprises a first current source and the second current regulator comprises a second current source.

8. The method of claim 6, further comprising:

controlling or setting the first current regulator at about the first predetermined current level; and

controlling or setting the second current regulator at about the second predetermined current level.

9. The method of claim 1, further comprising:

providing for the first, the second or a third segment of light emitting diodes to be in or out of the series light emitting diode current path at about a third predetermined current level or until the current level has reached about the third predetermined current level.

10. The method of claim 9, wherein the first, second and third predetermined current levels are non-sequential current levels.

11. The method of claim 9, wherein the steps of providing for the first, second and third segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

regulating the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

regulating the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is lower than the first predetermined current level; and

regulating the current level of the series light emitting diode current path at about the third predetermined current level or until the current level has reached about the third predetermined current level, the series light emitting diode current path comprising the third segment of light emitting diodes coupled in series to the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the third predetermined current level is greater than the first predetermined current level.

12. The method of claim 9, wherein the steps of providing for the first, second and third segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

regulating the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

regulating the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is greater than the first predetermined current level; and

regulating the current level of the series light emitting diode current path at about the third predetermined current level or until the current level has reached about the third predetermined current level, the series light emitting diode current path comprising the third segment of light emitting diodes coupled in series to the second segment of light emitting diodes, wherein the third predetermined current level is greater than the second predetermined current level.

13. The method of claim 1, wherein the steps of providing for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

regulating the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes without the second segment of light emitting diodes; and

regulating the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is lower than the first predetermined current level.

14. The method of claim 1, wherein the steps of providing for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

regulating the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes without the second segment of light emitting diodes; and

regulating the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is higher than the first predetermined current level.

15. The method of claim 1, wherein the steps of providing for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

turning off a first current regulator coupled to the first segment of light emitting diodes, the first current regulator providing for a maximum current at about the first predetermined current level; and

turning on a second current regulator coupled to the second segment of light emitting diodes, the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes in the series light emitting diode current path, the second current regulator providing for a maximum current at the second predetermined current level, wherein the second predetermined current level is lower than the first predetermined current level.

16. The method of claim 1, wherein the steps of providing for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path further comprise:

turning off a first current regulator coupled to the first segment of light emitting diodes, the first current regulator providing for a maximum current at about the first predetermined current level; and

turning on a second current regulator coupled to the second segment of light emitting diodes, the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes in the series light emitting diode current path, the second current regulator providing for a maximum current at the second predetermined current level, wherein the second predetermined current level is higher than the first predetermined current level.

17. The method of claim 1, further comprising:

providing for a next segment of light emitting diodes to be in or out of the series light emitting diode current path at about a next predetermined current level or until the current level has reached about the next predetermined current level.

18. The method of claim 1, wherein providing for the first segment of light emitting diodes to be in or out of the series light emitting diode current path and providing for the second segment of light emitting diodes to be in or out of the series light emitting diode current path occurs in a first order during a first part of an AC voltage interval and in a second order during a second part of the AC voltage interval, wherein the second order is the reverse of the first order.

19. The method of claim 1, further comprising:

determining whether the AC voltage is phase modulated; and

when the AC voltage is phase modulated, providing for the first segment of light emitting diodes to be in or out of the series light emitting diode current path corresponding to a phase modulated AC current level.

20. The method of claim 19, further comprising:

when the AC voltage is phase modulated, maintaining a parallel light emitting diode current path concurrently with providing for the second segment of light emitting diodes to be in or out of the series light emitting diode current path.

21. The method of claim 1, further comprising:

providing for the first segment of light emitting diodes to be in a first series light emitting diode current path; and

providing for the second segment of light emitting diodes to be in a second series light emitting diode current path in parallel with the first series light emitting diode current path.

22. The method of claim 1, further comprising:

during a first part of an AC voltage interval, providing for the first segment of light emitting diodes to be in a first series light emitting diode current path and providing for the second segment of light emitting diodes to be in a second series light emitting diode current path in parallel with the first segment of light emitting diodes;

with an increasing voltage level during the first part of the AC voltage interval, providing for a third segment of light emitting diodes to be in the first series light emitting diode current path and providing for a fourth segment of light emitting diodes to be in a third series light emitting diode current path in parallel with the third segment of light emitting diodes;

with an increasing voltage level during the first part of the AC voltage interval, providing for the second segment of light emitting diodes to be in the first series light emitting diode current path; and

with an increasing voltage level during the first part of the AC voltage interval, providing for the fourth segment of light emitting diodes to be in the first series light emitting diode current path.

23. The method of claim 22, further comprising:

with a decreasing voltage level during a second part of the AC voltage interval, providing for the fourth segment of light emitting diodes to be in parallel with the third segment of light emitting diodes;

with a decreasing voltage level during the second part of the AC voltage interval, providing for the second segment of light emitting diodes to be in parallel with the first segment of light emitting diodes; and

with a decreasing voltage level during the second part of the AC voltage interval, providing for the third and fourth segments of light emitting diodes to be out of the first series light emitting diode current path.

24. The method of claim 1, wherein selected segments of light emitting diodes of the plurality of segments of light emitting diodes each comprise light emitting diodes having light emission spectra of different colors or wavelengths.

25. An apparatus for providing power to a plurality of light emitting diodes couplable to receive an AC voltage, the plurality of light emitting diodes coupled in series to form a plurality of segments of light emitting diodes each comprising at least one light emitting diode, the apparatus further couplable to a current sensor, the apparatus comprising:

a first current regulator coupled to a first segment of light emitting diodes of the plurality of segments of light emitting diodes;

a second current regulator coupled to a second segment of light emitting diodes of the plurality of segments of light emitting diodes; and

a controller coupled to the first and second current regulators and couplable to the current sensor, the controller to monitor a current level through a series light emitting diode current path, to provide for the first segment of light emitting diodes to be in or out of the series light emitting diode current path at about a first predetermined current level or until the current level has reached about the first predetermined current level; and

to provide for the second segment of light emitting diodes to be in or out of the series light emitting diode current path at about a second predetermined current level or until the current level has reached about the second predetermined current level.

26. The apparatus of claim 25, further comprising:

a voltage regulator to provide a voltage or a current sufficient for at least one light emitting diode to be on and conducting during a zero crossing interval of the AC voltage.

27. The apparatus of claim 26, wherein the voltage regulator is charged during a peak interval of the AC voltage.

28. The apparatus of claim 26, wherein the voltage regulator comprises at least one capacitor coupled to a diode.

29. The apparatus of claim 26, wherein the voltage regulator comprises:

a first capacitor coupled to the first or second segment of light emitting diodes;

a first diode coupled to the first capacitor;

a second capacitor coupled in series to the first diode and the first capacitor; and

a second diode coupled to the second capacitor and to the first or second segment of light emitting diodes.

30. The apparatus of claim 26, wherein the voltage regulator is coupled to the first or second current regulator.

31. The apparatus of claim 25, wherein the controller further is to regulate the current level of the series light emitting diode current path to be less than or equal to a maximum current level.

32. The apparatus of claim 25, wherein the controller further is to provide for the first and second segments of light emitting diodes to be in or out of the series light emitting diode current path by respectively turning off or on the first current regulator and turning on or off the second current regulator.

33. The apparatus of claim 25, wherein the first current regulator comprises a first current source and the second current regulator comprises a second current source.

34. The apparatus of claim 33, wherein the first current source and the second current source each comprise a transistor.

35. The apparatus of claim 33, wherein the first current source and the second current source each comprise an operational amplifier coupled to a transistor.

36. The apparatus of claim 33, wherein the first current source and the second current source each comprise an operational amplifier coupled to a plurality of transistors.

37. The apparatus of claim 25, wherein the controller further is to control or set the first current regulator at about the first predetermined current level and control or set the second current regulator at about the second predetermined current level.

38. The apparatus of claim 25, further comprising:

a third current regulator coupled to a third segment of light emitting diodes of the plurality of segments of light emitting diodes;

wherein the controller further is to provide for the first, second or third segment of light emitting diodes to be in or out of the series light emitting diode current path at about a third predetermined current level or until the current level has reached about the third predetermined current level.

39. The apparatus of claim 38, wherein the first, second and third predetermined current levels are non-sequential current levels.

40. The apparatus of claim 38, wherein the controller further is to turn on the first current regulator to control the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

to turn off the first current regulator and turn on the second current regulator to control the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is lower than the first predetermined current level; and

to turn on the third current regulator and turn off the second current regulator to control the current level of the series light emitting diode current path at about the third predetermined current level or until the current level has reached about the third predetermined current level, the series light emitting diode current path comprising the third segment of light emitting diodes coupled in series to the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the third predetermined current level is greater than the first predetermined current level.

41. The apparatus of claim 38, wherein the controller further is to turn on the first current regulator to control the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

to turn off the first current regulator and turn on the second current regulator to control the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is greater than the first predetermined current level; and

to turn on the third current regulator and turn off the second current regulator to control the current level of the series light emitting diode current path at about the third predetermined current level or until the current level has reached about the third predetermined current level, the series light emitting diode current path comprising the third segment of light emitting diodes coupled in series to the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the third predetermined current level is greater than the second predetermined current level.

42. The apparatus of claim 25, wherein the controller further is to turn on the first current regulator to control the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

and to turn off the first current regulator and turn on the second current regulator to control the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is lower than the first predetermined current level.

43. The apparatus of claim 25, wherein the controller further is to turn on the first current regulator to control the current level of the series light emitting diode current path at about the first predetermined current level or until the current level has reached about the first predetermined current level, the series light emitting diode current path comprising the first segment of light emitting diodes and not the second segment of light emitting diodes;

and to turn off the first current regulator and turn on the second current regulator to control the current level of the series light emitting diode current path at about the second predetermined current level or until the current level has reached about the second predetermined current level, the series light emitting diode current path comprising the second segment of light emitting diodes coupled in series to the first segment of light emitting diodes, wherein the second predetermined current level is greater than the first predetermined current level.

44. The apparatus of claim 25, wherein the controller further is to provide for a next segment of light emitting diodes to be in or out of the series light emitting diode current path at about a next predetermined current level or until the current level has reached about the next predetermined current level.

45. The apparatus of claim 25, wherein the controller further is to provide for the first segment of light emitting diodes to be in or out of the series light emitting diode current path and provide for the second segment of light emitting diodes to be in or out of the series light emitting diode current path in a first order during a first part of an AC voltage interval and in a second order during a second part of the AC voltage interval, wherein the second order is the reverse of the first order.

46. The apparatus of claim 25, wherein the controller further is to determine whether the AC voltage is phase modulated;

and when the AC voltage is phase modulated, to provide for the first segment of light emitting diodes to be in or out of the series light emitting diode current path corresponding to a phase modulated AC current level.

47. The apparatus of claim 41, wherein the controller further is to provide for a parallel light emitting diode current path concurrently with providing for the first or second segment of light emitting diodes to be in or out of the series light emitting diode current path.

48. The apparatus of claim 25, wherein the controller further is to provide for the first segment of light emitting diodes to be in a first series light emitting diode current path;

and to provide for the second segment of light emitting diodes to be in a second series light emitting diode current path in parallel with the first series light emitting diode current path.

49. The apparatus of claim 25, further comprising:

a rectifier couplable to receive the AC voltage.

50. The apparatus of claim 25, wherein selected segments of light emitting diodes of the plurality of segments of light emitting diodes each comprise light emitting diodes having light emission spectra of different colors or wavelengths.

51. The apparatus of claim 50, wherein the controller further is to selectively provide for the selected segments of light emitting diodes to be in or out of the series light emitting diode current path to provide a corresponding lighting effect.

52. The apparatus of claim 50, wherein the controller further is to selectively provide for the selected segments of light emitting diodes to be in or out of the series light emitting diode current path to provide a corresponding color temperature.

53. The apparatus of claim 25, wherein the apparatus operates at about a rectified AC voltage frequency selected from the group consisting of:

100 Hz, 120 Hz, 300 Hz, 360 Hz, 400 Hz, and combinations thereof.

54. The apparatus of claim 25, further comprising:

a plurality of phosphor coatings or layers, each phosphor coating or layer coupled to a corresponding light emitting diode of the plurality of light emitting diodes, each phosphor coating or layer having a luminous decay time constant between about 2 to 3 msec.

55. The apparatus of claim 25, wherein the apparatus is further couplable to a third segment of light emitting diodes of the plurality of segments of light emitting diodes and to a fourth segment of light emitting diodes of the plurality of segments of light emitting diodes, the apparatus further comprising:

a plurality of switches, each switch of the plurality of switches coupled to at least one of the first, second, third or fourth first segments of light emitting diodes and coupled to the controller;

wherein during a first part of an AC voltage interval, the controller is to provide for the first segment of light emitting diodes to be in a first series light emitting diode current path and provide for the second segment of light emitting diodes to be in a second series light emitting diode current path in parallel with the first segment of light emitting diodes;

with an increasing voltage level during the first part of the AC voltage interval, the controller is to provide for the third segment of light emitting diodes to be in the first series light emitting diode current path and providing for the fourth segment of light emitting diodes to be in a third series light emitting diode current path in parallel with the third segment of light emitting diodes;

with an increasing voltage level during the first part of the AC voltage interval, the controller is to provide for the second segment of light emitting diodes to be in the first series light emitting diode current path; and

with an increasing voltage level during the first part of the AC voltage interval, the controller is to provide for the fourth segment of light emitting diodes to be in the first series light emitting diode current path.

56. The apparatus of claim 55, wherein with a decreasing voltage level during a second part of the AC voltage interval, the controller is to provide for the fourth segment of light emitting diodes to be in parallel with the third segment of light emitting diodes;

with a decreasing voltage level during the second part of the AC voltage interval, the controller is to provide for the second segment of light emitting diodes to be in parallel with the first segment of light emitting diodes; and

with a decreasing voltage level during the second part of the AC voltage interval, the controller is to provide for the third and fourth segments of light emitting diodes to be out of the first series light emitting diode current path.

57. An apparatus couplable to receive an AC voltage, the apparatus comprising:

a plurality of light emitting diodes coupled in series to form at least one segment of light emitting diodes;

a first current regulator coupled at a light emitting diode cathode of the at least one segment of light emitting diodes;

a second current regulator coupled at a light emitting diode anode of the at least one segment of light emitting diodes;

a current sensor;

a voltage regulator to provide a voltage or a current sufficient for at least one light emitting diode to be on and conducting; and

a controller coupled to the first and second current regulators and to the current sensor, the controller to monitor a current level through the at least one segment of light emitting diodes, to turn on the second current regulator to provide current through the at least one segment of light emitting diodes and to charge the voltage regulator, and to turn on the first current regulator to provide current through the at least one segment of light emitting diodes and to discharge the voltage regulator.