Adaptive Current Regulation for Solid State Lighting

• US 20100213859A1
• Filed: 12/16/2009
• Published: 08/26/2010
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Chemtron Research LLC (Intellectual Ventures LLC)
• Original Assignee: Exclara, Inc. (Million Star Technology Ltd.)
• Inventors: Rodriguez, Harry, Shteynberg, Anatoly, Zhou, Dongsheng, Lehman, Bradley M.
• Granted Patent: US 8,441,210 B2
• Time in Patent Office: Days
• US Class Current: 315/224
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/385 using flyback topology
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

Exemplary embodiments provide an apparatus, system and method for power conversion to provide power to solid state lighting, and which may be coupled to a first switch, such as a dimmer switch. An exemplary system for power conversion comprises: a switching power supply comprising a second, power switch; solid state lighting coupled to the switching power supply; a voltage sensor; a current sensor; a memory; a first adaptive interface circuit to provide a resistive impedance to the first switch and conduct current from the first switch in a default mode; a second adaptive interface circuit to create a resonant process when the first switch turns on; and a controller to modulate the second adaptive interface circuit when the first switch turns on to provide a current path during the resonant process of the switching power supply.

Claims

1. A method of interfacing a switching power supply to a first switch coupled to an alternating current (AC) power source for providing power to solid state lighting, the method comprising:

sensing an input current level;

sensing an input voltage level;

using a first adaptive interface circuit, providing a resistive impedance to the first switch and conducting current from the first switch in a default mode; and

using a second adaptive interface circuit, when the first switch turns on, creating a resonant process and providing a current path during the resonant process of the switching power supply.

2. The method of claim 1, wherein the first switch is a phase-modulated dimmer switch.

3. The method of claim 1, further comprising:

using the second adaptive interface circuit to modulate a current of the first switch during the resonant process of the switching power supply.

4. The method of claim 1, further comprising:

using a third adaptive interface circuit to modulate a current of the first switch during the resonant process of the switching power supply.

5. The method of claim 1, further comprising:

using the first adaptive interface circuit to conduct current during a start up state or a gradual start state of the switching power supply.

6. The method of claim 5, further comprising:

using the first adaptive interface circuit to conduct current during charging of a trigger capacitor of the first switch, during turn on of the first switch, and during conduction of the first switch.

7. The method of claim 1, wherein the step of providing a resistive impedance further comprises:

switching the first adaptive interface circuit to provide a constant resistive impedance to the first switch.

8. The method of claim 1, wherein the step of providing a resistive impedance further comprises:

modulating the first adaptive interface circuit to provide a variable resistive impedance to the first switch.

9. The method of claim 1, wherein the step of providing a resistive impedance further comprises:

building an operational voltage; and

when the operational voltage has reached a predetermined level, modulating the first adaptive interface circuit and transitioning to a gradual start of the switching power supply asynchronously to the state of the first switch.

10. The method of claim 1, wherein the step of providing a current path during the resonant process further comprises:

determining a peak input current level; and

switching a resistive impedance to create the current path.

11. The method of claim 1, wherein the step of providing a current path during the resonant process further comprises:

determining a peak input current level; and

modulating a switched, resistive impedance to create the current path.

12. The method of claim 1, further comprising:

during a full power mode of the switching power supply and during charging of a trigger capacitor of the first switch, operating the switching power supply at a one-hundred percent duty cycle or in a DC mode.

13. The method of claim 1, further comprising:

during a full power mode of the switching power supply and during turning on of the first switch, operating the switching power supply at a substantially maximum instantaneous power for a predetermined period of time.

14. The method of claim 1, wherein the second adaptive interface circuit comprises an inductor in parallel with a resistor, and wherein the method further comprises:

during a full power mode of the switching power supply and during turning on of the first switch, operating the switching power supply at a substantially maximum instantaneous power until the inductor has substantially discharged.

15. The method of claim 1, further comprising:

using the second adaptive interface circuit to conduct current during a full operational power state of the switching power supply.

16. The method of claim 1, further comprising:

adjusting a minimum power from the first switch during a gradual start phase of the switching power supply.

17. The method of claim 1, wherein the second adaptive interface circuit further comprises a switchable resistive impedance, and wherein the method further comprises:

using the second adaptive interface circuit to provide a current path during a start up phase of the switching power supply, during a gradual start up of the switching power supply, or during a full operational mode of the switching power supply.

18. The method of claim 1, further comprising:

using an operational voltage bootstrap circuit coupled to the switching power supply to generate an operational voltage.

19. The method of claim 18, wherein the first adaptive interface circuit further comprises the operational voltage bootstrap circuit.

20. The method of claim 1, further comprising:

determining a maximum duty cycle corresponding to the sensed input voltage level;

providing a pulse width modulation operating mode for the switching power supply using a switching duty cycle less than the maximum duty cycle; and

when the duty cycle is within a predetermined range of the maximum duty cycle, providing a current pulse operating mode for the switching power supply.

21. The method of claim 20, further comprising:

determining or obtaining from a memory a maximum duty cycle corresponding to the sensed input voltage level.

22. The method of claim 20, further comprising:

determining or varying the duty cycle to provide a predetermined or selected average or peak output current level.

23. The method of claim 20, further comprising:

determining a peak output current level up to a maximum voltseconds parameter.

24. The method of claim 1, further comprising:

detecting a malfunction of the first switch.

25. The method of claim 24, further comprising:

detecting the malfunction by determining at least two input voltage peaks or two input voltage zero crossings during a half-cycle of the AC power source.

26. A system for power conversion, the system couplable to a first switch coupled to an alternating current (AC) power source, the system comprising:

a switching power supply comprising a second, power switch;

solid state lighting coupled to the switching power supply;

a voltage sensor;

a current sensor;

a memory;

a first adaptive interface circuit comprising a resistive impedance to conduct current from the first switch in a default mode;

a second adaptive interface circuit to create a resonant process when the first switch turns on; and

a controller coupled to the voltage sensor, to the current sensor, to the memory, to the second switch, to the first adaptive interface circuit and to the second adaptive interface circuit, and when the first switch turns on, the controller to modulate the second adaptive interface circuit to provide a current path during the resonant process of the switching power supply.

27. The system of claim 26, wherein the first switch is a phase-modulated dimmer switch.

28. The system of claim 26, wherein the controller further is to modulate the second adaptive interface circuit to modulate a current of the first switch during the resonant process of the switching power supply.

29. The system of claim 26, further comprising:

a third adaptive interface circuit to modulate a current of the first switch during the resonant process of the switching power supply.

30. The system of claim 26, wherein the controller further is to use the first adaptive interface circuit to conduct current during a start up state or a gradual start state of the switching power supply.

31. The system of claim 30, wherein the controller further is to use the first adaptive interface circuit to conduct current during charging of a trigger capacitor of the first switch, during turn on of the first switch, and during conduction of the first switch.

32. The system of claim 26, wherein the controller further is to switch the first adaptive interface circuit to provide a constant resistive impedance to the first switch.

33. The system of claim 26, wherein the controller further is to modulate the first adaptive interface circuit to provide a variable resistive impedance to the first switch.

34. The system of claim 26, wherein when an operational voltage has reached a predetermined level, the controller further is to modulate the first adaptive interface circuit and transition to a gradual start of the switching power supply asynchronously to the state of the first switch.

35. The system of claim 26, wherein the second adaptive interface circuit comprises a resistive impedance, wherein the controller further is to determine a peak input current level, and when the peak input current level has been reached, the controller further is to switch the resistive impedance to create the current path.

36. The system of claim 26, wherein the second adaptive interface circuit comprises a switched resistive impedance, wherein the controller further is to determine a peak input current level, and when the peak input current level has been reached, the controller further is to modulate the switched, resistive impedance to create the current path.

37. The system of claim 26, wherein during a full power mode of the switching power supply and during charging of a trigger capacitor of the first switch, the controller further is to operate the switching power supply at a one-hundred percent duty cycle or in a DC mode.

38. The system of claim 26, wherein during a full power mode of the switching power supply and during turning on of the first switch, the controller further is to operate the switching power supply at a substantially maximum instantaneous power for a predetermined period of time.

39. The system of claim 26, wherein the second adaptive interface circuit comprises an inductor in parallel with a resistor, and wherein during a full power mode of the switching power supply and during turning on of the first switch, the controller further is to operate the switching power supply at a substantially maximum instantaneous power until the inductor has substantially discharged.

40. The system of claim 26, the controller further is to use the second adaptive interface circuit to conduct current during a full operational power state of the switching power supply.

41. The system of claim 26, the controller further is to adjust a minimum power from the first switch during a gradual start phase of the switching power supply.

42. The system of claim 26, wherein the second adaptive interface circuit further comprises a switchable resistive impedance, and wherein the controller further is to use the second adaptive interface circuit to provide a current path during a start up phase of the switching power supply, during a gradual start up of the switching power supply, or during a full operational mode of the switching power supply.

43. The system of claim 26, further comprising:

an operational voltage bootstrap circuit coupled to the switching power supply to generate an operational voltage.

44. The system of claim 43, wherein the first adaptive interface circuit further comprises the operational voltage bootstrap circuit.

45. The system of claim 26, wherein the controller further is to determine a maximum duty cycle corresponding to the sensed input voltage level;

provide a pulse width modulation operating mode for the switching power supply using a switching duty cycle less than the maximum duty cycle; and

when the duty cycle is within a predetermined range of the maximum duty cycle, provide a current pulse operating mode for the switching power supply.

46. The system of claim 45, wherein the controller further is to determine or obtain from a memory a maximum duty cycle corresponding to the sensed input voltage level.

47. The system of claim 45, wherein the controller further is to determine or vary the duty cycle to provide a predetermined or selected average or peak output current level.

48. The system of claim 45, wherein the controller further is to determine a peak output current level up to a maximum voltseconds parameter.

49. The system of claim 26, wherein the controller further is to detect a malfunction of the first switch.

50. The system of claim 49, wherein the controller further is to detect the malfunction by determining at least two input voltage peaks or two input voltage zero crossings during a half-cycle of the AC power source.

51. The system of claim 26, wherein the first adaptive interface circuit comprises:

a first resistor;

a transistor coupled in series to the first resistor, the transistor having a base or having a gate coupled to the controller; and

a second resistor coupled to the base or to the gate of the transistor.

52. The system of claim 26, wherein the first adaptive interface circuit comprises:

a first resistor;

a transistor coupled in series to the first resistor, the transistor having a base or having a gate coupled to the controller;

a second resistor coupled to a source or an emitter of the transistor; and

a zener diode coupled to the base or gate of the transistor and coupled to the second resistor.

53. The system of claim 26, wherein the second adaptive interface circuit comprises:

an inductor; and

a resistor coupled in parallel to the inductor.

54. The system of claim 26, wherein the second adaptive interface circuit comprises:

an inductor;

a first resistor the inductor;

a transistor having a base or a gate coupled to the first resistor.

55. The system of claim 54, wherein the second adaptive interface circuit further comprises:

a second resistor coupled to the inductor and coupled to a collector or drain of the transistor;

a first, zener diode coupled to an emitter or source of the transistor; and

a second diode coupled to the inductor and to the first zener diode.

56. The system of claim 26, wherein the second adaptive interface circuit comprises:

an inductor;

a first resistor;

a differentiator;

a one shot circuit coupled to an output of the differentiator; and

a transistor coupled in series to the first resistor and further having a gate or base coupled to an output of the one shot circuit.

57. The system of claim 26, wherein the solid state lighting is one or more light emitting diodes.

58. The system of claim 26, wherein the switching power supply has a flyback configuration.

59. The system of claim 26, wherein the system has a form factor compatible with an A19 standard.

60. The system of claim 26, wherein the system is couplable through a rectifier to the first switch.

61. The system of claim 26, wherein the system is couplable through a rectifier and an inductor to the first switch.

75. The system of claim 43, wherein the first adaptive interface circuit further comprises an operational voltage bootstrap circuit.

80. The system of claim 54, wherein the second adaptive interface circuit further comprises:

a second resistor coupled to the inductor and coupled to a collector or drain of the transistor;

a first, zener diode coupled to an emitter or source of the transistor; and

a second diode coupled to the inductor and to the first zener diode.

62. An apparatus for power conversion, the apparatus couplable to a first, phase-modulated dimmer switch coupled to an alternating current (AC) power source, the apparatus couplable to a solid state lighting, the apparatus comprising:

a switching power supply comprising a second, power switch;

a voltage sensor;

a current sensor;

a memory;

a first adaptive interface circuit comprising a resistive impedance to conduct current from the first switch in a default mode;

a second adaptive interface circuit to create a resonant process when the first switch turns on; and

a controller coupled to the voltage sensor, to the current sensor, to the memory, to the second switch, to the first adaptive interface circuit and to the second adaptive interface circuit, and when the first switch turns on, the controller to modulate the second adaptive interface circuit to provide a current path and to modulate a current of the first switch during the resonant process of the switching power supply.

63. The apparatus of claim 62, further comprising:

a third adaptive interface circuit to modulate a current of the first switch during the resonant process of the switching power supply.

64. The apparatus of claim 62, wherein the controller further is to use the first adaptive interface circuit to conduct current during a start up state or a gradual start state of the switching power supply.

65. The apparatus of claim 64, wherein the controller further is to use the first adaptive interface circuit to conduct current during charging of a trigger capacitor of the first switch, during turn on of the first switch, and during conduction of the first switch.

66. The apparatus of claim 62, wherein the controller further is to switch the first adaptive interface circuit to provide a constant resistive impedance to the first switch.

67. The apparatus of claim 62, wherein the controller further is to modulate the first adaptive interface circuit to provide a variable resistive impedance to the first switch.

68. The apparatus of claim 62, wherein when an operational voltage has reached a predetermined level, the controller further is to modulate the first adaptive interface circuit and transition to a gradual start of the switching power supply asynchronously to the state of the first switch.

69. The apparatus of claim 62, wherein the second adaptive interface circuit comprises a resistive impedance, wherein the controller further is to determine a peak input current level, and when the peak input current level has been reached, the controller further is to switch the resistive impedance to create the current path.

70. The apparatus of claim 62, wherein the second adaptive interface circuit comprises a switched resistive impedance, wherein the controller further is to determine a peak input current level, and when the peak input current level has been reached, the controller further is to modulate the switched, resistive impedance to create the current path.

71. The apparatus of claim 62, wherein during a full power mode of the switching power supply and during charging of a trigger capacitor of the first switch, the controller further is to operate the switching power supply at a one-hundred percent duty cycle or in a DC mode.

72. The apparatus of claim 62, wherein during a full power mode of the switching power supply and during turning on of the first switch, the controller further is to operate the switching power supply at a substantially maximum instantaneous power for a predetermined period of time.

73. The apparatus of claim 62, wherein the second adaptive interface circuit comprises an inductor in parallel with a resistor, and wherein during a full power mode of the switching power supply and during turning on of the first switch, the controller further is to operate the switching power supply at a substantially maximum instantaneous power until the inductor has substantially discharged.

76. The apparatus of claim 62, wherein the controller further is to determine a maximum duty cycle corresponding to the sensed input voltage level;

provide a pulse width modulation operating mode for the switching power supply using a switching duty cycle less than the maximum duty cycle; and

when the duty cycle is within a predetermined range of the maximum duty cycle, provide a current pulse operating mode for the switching power supply.

77. The apparatus of claim 62, wherein the controller further is to detect a malfunction of the first switch by determining at least two input voltage peaks or two input voltage zero crossings during a half-cycle of the AC power source.

78. The apparatus of claim 62, wherein the second adaptive interface circuit comprises:

an inductor; and

a resistor coupled in parallel to the inductor.

79. The apparatus of claim 62, wherein the second adaptive interface circuit comprises:

an inductor;

a first resistor the inductor;

a transistor having a base or a gate coupled to the first resistor.

81. The apparatus of claim 62, wherein the second adaptive interface circuit comprises:

an inductor;

a first resistor;

a differentiator;

a one shot circuit coupled to an output of the differentiator; and

a transistor coupled in series to the first resistor and further having a gate or base coupled to an output of the one shot circuit.

82. A system for power conversion, the system having a form factor compatible with an A19 standard, the system couplable to a phase-modulating dimmer switch coupled to an alternating current (AC) power source, the system comprising:

a switching power supply comprising a power switch;

at least one light emitting diode coupled to the switching power supply;

a voltage sensor to sense an input voltage level;

a first adaptive interface circuit to conduct current from the dimmer switch in a default mode, the first adaptive interface circuit further providing a substantially matching impedance to the dimmer switch;

a second adaptive interface circuit to create a resonant process of the switching power supply and to provide a current path during the resonant process of the switching power supply;

a memory; and

a controller coupled to the first voltage sensor, to the memory and to the power switch, the controller to provide a pulse width modulation operating mode using a duty cycle less than a maximum duty cycle, and when the duty cycle is within a predetermined range of the maximum duty cycle, to provide a current pulse operating mode.