Electronic light generating element light bulb

• US 20050237005A1
• Filed: 08/09/2004
• Published: 10/27/2005
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Lighting Science Group Corporation (Pegasus Capital Advisors, L.P.)
• Original Assignee: Lighting Science Group Corporation (Pegasus Capital Advisors, L.P.)
• Inventors: Maxik, Fredric
• Granted Patent: US 7,215,086 B2
• Time in Patent Office: Days
• US Class Current: 315/247
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/327 Burst dimming
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• 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
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

The present system for driving an electronic light generating element, includes: (i) input terminals, (ii) an input circuit coupled to the input terminals and operable to convert a sinusoidal signal to a signal independent of negative current attributes, (iii) a switch control circuit coupled to the input circuit and operable to generate a switching signal having pulses, and (iv) a switching element coupled to the input circuit and the switch control circuit. The switching element is operable to generate an output signal formed as a series of bursts having peak amplitudes above a maximum forward current rating for a duty cycle less than a maximum operating duty cycle over which an electronic light generating element may be catastrophically damaged in response to the signal independent of negative current attributes and switching being applied to the switching element. The output signal is applied to the electronic light generating element to produce light.

Claims

1. A circuit for driving an electronic light generating element, said circuit comprising:

an input circuit coupled to said input terminals and operable to convert a sinusoidal signal to a signal that is independent of negative current attributes;

a switch control circuit coupled to said input circuit and operable to generate a switching signal having pulses; and

a switching element coupled to said input circuit and said switch control circuit and operable to generate an output signal formed as a series of bursts, at least one of the series of bursts having a peak amplitude above a maximum forward current rating of the electronic light generating element, and being applied to the electronic light generating element to produce light.

2. The circuit according to claim 1, wherein said switching element generates the series of bursts for a duty cycle less than a maximum operating cycle over which an electronic light generating element may be at least partially catastrophically damaged in response to the output signal.

3. The circuit according to claim 2, wherein the catastrophic failure is a thermal breakdown at a junction of two oppositely charged substrates of the electronic light generating element.

4. The circuit according to claim 1, wherein the electronic light generating element is a light emitting diode.

5. The circuit according to claim 1, wherein the circuit is included in a light bulb including a housing and a base.

6. The circuit according to claim 5, wherein at least a portion of the circuit is located in the base of the light bulb.

7. The circuit according to claim 1, wherein the duty cycle is less than approximately ten percent.

8. The circuit according to claim 1, further comprising:

a pair of input terminals coupled to the input circuit; and

a comparator coupled to said input terminals and operable to sense a change in voltage input to the input circuit to alter the output signal.

10. The circuit according to claim 1, wherein the series of bursts are substantially periodic.

9. The circuit according to clam 8, wherein the alteration of the output signal includes adjusting the frequency of the series of bursts.

11. A method for driving an electronic light generating element, said method comprising:

converting a sinusoidal signal to a signal independent of negative current attributes;

generating a switching signal having pulses;

generating an output signal formed as a series of bursts, at least one of the series of bursts having a peak amplitude above a maximum forward current rating of said electronic light generating element; and

applying the output signal to the electronic light generating element to produce light.

12. The method according to claim 11, wherein said generating an output signal generates the bursts for a duty cycle less than a maximum operating duty cycle over which an electronic light generating element may be at least partially catastrophically damaged in response to the output signal.

13. The method according to claim 11, wherein said applying the output signal to the electronic light generating element includes applying the output signal to a light emitting diode.

14. The method according to claim 11, wherein the driving of the electronic light generating element is performed within a light bulb.

15. The method according to claim 14, wherein said converting of the sinusoidal signal is performed within a base of the light bulb.

16. The method according to claim 11, wherein said generating the output signal produces the duty cycle of less than approximately ten percent.

17. The method according to claim 11, wherein the catastrophic failure is a thermal breakdown at a junction of two oppositely charged substrates of the electronic light generating element.

18. The method according to claim 11, further comprising:

sensing a change in the sinusoidal signal prior to said converting; and

altering the output signal in response to said sensing a change in the sinusoidal signal.

19. The method according to claim 18, wherein said altering the output signal includes changing the frequency of the series of bursts.

20. A device for driving an electronic light generating element, said device comprising:

means for converting a sinusoidal signal to a signal independent of negative current attributes;

means for generating a switching signal having pulses;

means for generating an output signal in communication with said means for converting; and

means for generating a switching signal, the output signal formed as a series of bursts having peak amplitudes above a maximum forward current rating for the electronic light generating element; and

means for applying the output signal to the electronic light generating element to produce light.

21. The device according to claim 20, wherein said means for generating an output signal further comprises:

means for producing the series of pulses for a duty cycle less than a maximum operating duty cycle over which an electronic light generating element may be at least partially catastrophically damaged in response to receiving the signal independent of negative current attributes.

22. The device according to claim 20, further comprising:

means for sensing a change in the sinusoidal signal prior to said converting; and

means for altering the output signal in response to said means for sensing a change in the sinusoidal signal indicating a change to said means for altering.

23. A light source, comprising:

an electronic light generating element having a maximum forward current rating (max IF); and

a power circuit having an output connected to said electronic light generating element, the output capable of applying a forward voltage (V_F) to said LED that drives forward current (I_F) for said electronic light generating element above the maximum forward current rating (max I_F) up to a maximum current value (I_max), said LED providing radiant power when said power circuit is connected to a power source.

24. The light source according to claim 23, wherein said power circuit generates the output for a duty cycle less than a maximum operating duty cycle (DC_max) over which said electronic light generating element is at least partially catastrophically damaged.

25. The light source according to claim 24, wherein the duty cycle is increased above the maximum operating percentage (DC_max) as the forward current (I_F) is decreased below the maximum current value (I_max).

26. The light source according to claim 24, wherein the maximum current value (I_max) is less than about three times the maximum forward current rating (max I_F) and the maximum operating percentage of the duty cycle no greater than ten percent (10%) at the maximum current value (I_max).

27. The light source according to claim 24, further comprising dimmer and comparator electronic components, said comparator component operable to detect a change in voltage applied to said power circuit by said dimmer to cause either the amplitude of the forward current (I_F) to be reduced or pulses for driving the forward current to be reduced in frequency.

28. The light source according to claim 23, wherein the light source is a light bulb.

29. The light source according to claim 23, wherein the light bulb includes a base configured as an Edison base.

30. An apparatus comprising:

an electronic light generator having a maximum current rating; and

a circuit producing an electric signal that drives said electronic light generator, said electric signal including a pulse train that has a plurality of first pulses and a plurality of second pulses, the amplitudes of said second pulses being less than the amplitudes of said first pulses, and said pulse train being configured as successive groups of pulses that each start with one of said first pulses and that each include at least one of said second pulses, at least some of said pulses of said pulse train having a peak current value above said maximum current rating, said output signal being in excess of said maximum current rating less than ten percent of the time.

31. The apparatus according to claim 30, wherein said pulses each have a rise time to a peak value, and have a fall time from the peak value that is longer than the rise time.

32. The apparatus according to claim 30, wherein said groups have respective time durations that are approximately equal.

33. The apparatus according to claim 30, wherein said circuit selectively varies a frequency of said pulse train.

34. The apparatus according to claim 30, wherein each said group includes at least two of said second pulses.

35. The apparatus according to claim 30, wherein said electronic light generator is a light emitting diode.

36. A method comprising generating a electric signal for driving an electronic light generator having a maximum current rating, said electric signal including a pulse train that has a plurality of first pulses and a plurality of second pulses, the amplitudes of said second pulses being less than the amplitudes of said first pulses, and said pulse train being configured as successive groups of pulses that each start with one of said first pulses and that each include at least one of said second pulses, at least some of said pulses of said pulse train having a peak current value above said maximum current rating, said output signal being in excess of said maximum current rating less than ten percent of the time.

37. The apparatus according to claim 36, wherein said generating includes causing said pulses to each have a rise time to a peak value, and to have a fall time from the peak value that is longer than the rise time.

38. The apparatus according to claim 36, wherein said generating includes configuring said groups to have respective time durations that are approximately equal.

39. The apparatus according to claim 36, wherein said generating includes selectively varying a frequency of said pulse train.

40. The apparatus according to claim 36, wherein said generating includes configuring each said group to have at least two of said second pulses.

41. The apparatus according to claim 36, including selecting a light emitting diode to serve as said electronic light generator.