SOLID STATE LIGHTING DEVICES UTILIZING MEMRISTORS

• US 20110285309A1
• Filed: 05/18/2010
• Published: 11/24/2011
• Est. Priority Date: 05/18/2010
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: Cree Lighting Company (Ideal Industries Incorporated)
• Inventors: VAN DE VEN, Antony Paul
• Granted Patent: US 9,807,825 B2
• Time in Patent Office: Days
• US Class Current: 315/291
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/28 using temperature feedback
• CPC Class Codes: H05B 45/37 Converter circuits

Abstract

LED chip circuits, solid state light engines and SSL luminaires are disclosed that utilize memristors to vary LED chip emission. In different embodiments the resistance of said memristor can be varied to vary the drive signal applied to one or more LED chips, thereby varying the LED chip emission intensity. The present invention can be used in much different arrangement to vary LED chip emission, such as changing the drive signals to LED chips that experience changes in emission intensity at different temperatures or that experience emission intensity depreciation over time.

Claims

1. A light emitting diode (LED) chip circuit, comprising:

an LED chip; and

a memristor arranged to vary the emission intensity of said LED chip.

2. The LED chip circuit of claim 1, wherein said memristor varies the drive signal applied to said LED chip.

3. The LED chip circuit of claim 1, wherein said emission intensity is varied in response to changes in the resistance provided by said memristor.

4. The LED chip circuit of claim 1, wherein the emission of said LED chip varies over time, said memristor varying said drive signal over time to compensate for at least a portion of said variation.

5. The LED chip circuit of claim 1, wherein the emission of said LED chip depreciates over time, said memristor increasing said drive signal to said LED chip to compensate for at least a portion of said depreciation.

6. The LED chip circuit of claim 1, wherein the emission of said LED chip varies at different operating temperatures, said memristor varying said drive signal to compensate for at least a portion of said variation.

7. The LED chip circuit of claim 1, wherein said memristor is arranged to increase the drive signal applied to said LED chip over time.

8. The LED chip circuit of claim 1, wherein said memristor is arranged to decrease the drive signal applied to said LED chip over time.

9. The LED chip circuit of claim 1, wherein said memristor is arranged to increase or decrease the drive signal applied to said LED chip.

10. The LED chip circuit of claim 1, wherein said memristor is arranged in a resistor circuit coupled to said LED, wherein the change in said resistance provided by said memristor changes the resistance of said resistor circuit.

11. The LED chip circuit of claim 10, wherein said resistor circuit comprises a memristor coupled in parallel with a resistor.

12. The LED chip circuit of claim 10, wherein said resistor circuit is coupled to a red emitting LED chip.

13. The LED chip circuit of claim 1, wherein said memristor is arranged in a bypass circuit.

14. The LED chip circuit of claim 13, further comprising a second LED chip arranged in series with said LED chip, said bypass circuit coupled across said LED chip.

15. The LED chip circuit of claim 14, wherein a decrease in resistance from said memristor cause an increase in current bypassing said LED chip through said bypass circuit.

16. The LED chip circuit of claim 15, wherein said LED chip is BSY LED chip and said second LED chip is a red emitting LED chip.

17. A solid state luminaire comprising:

a first light emitting diode (LED) chip that can experience changes in emission over time or in response to changes in temperature; and

a memristor arranged to vary the drive signal applied to said first LED chip to compensate for said emission changes.

18. The solid state emitter of claim 17, wherein the resistance of said memristor is varied to vary said drive signal.

19. The solid state luminaire of claim 17, further comprising a second LED chip, said memristor varying the drive signal to said first LED chip to maintain a desired combination of light from said first and second LED chips.

20. The solid state luminaire of claim 17, wherein the emission of said first LED chip varies over time, said memristor varying said drive signal to compensate for said variation.

21. The solid state luminaire of claim 17, wherein the emission of said first LED chip depreciates over time, said memristor increasing said drive signal to compensate for said depreciation.

22. The solid state luminaire of claim 17, wherein the emission of said first LED chip decreases as the operating temperature increases, said memristor varying said drive signal to compensate for said decrease.

23. The solid state luminaire of claim 17, wherein said memristor is arranged in resistor circuit coupled to said first LED chip, wherein the change in said resistance provided by said memristor changes the resistance of said resistor circuit.

24. The solid state luminaire of claim 17, wherein said memristor is arranged in a bypass circuit.

25. A solid state light engine comprising:

a light emitting diode (LED) chip array comprising first LED chips emitting at one color of light and second LED chips emitting a different color of light, wherein the emission of said first and second LED chips depreciates over time at different rates; and

a memristor arranged to vary the drive signal applied to said first LED chips to compensate for said different rates of emission depreciation.

26. The solid state light engine of claim 25, wherein the resistance of said memristor is varied to vary said drive signal.

27. The solid state light engine of claim 25, wherein said memristor varies the drive signal to said first LED chip to maintain a desired combination of light from said first and second LED chips.

28. The solid state light engine of claim 25, wherein said memristor increases said drive signal over time.

29. The solid state light engine of claim 25, wherein said memristor is arranged in resistor circuit coupled to one of said first and second LED chips, wherein the change in said resistance provided by said memristor changes the resistance of said resistor circuit.

30. The solid state luminaire, comprising:

a housing having a housing opening;

a light engine arranged in said housing with an array of LED chips comprising first and second LED chips emitting at different colors of light, the light from said first and second LED chips emitting out said housing opening; and

a memristor to vary the emission at least one of said first and second LED chips.

31. The solid state luminaire of claim 30, further comprising a mounting mechanism to mount said housing.

32. The solid state luminaire of claim 30, wherein the resistance of said memristor is varied to vary said vary the emission.

33. The solid state luminaire of claim 30, wherein said memristor varies the drive signal to at least one of said first LED chips over time to maintain a desired combination of light from said first and second LED chips.

34. A solid state lighting device, comprising:

an LED;

a memristor that receives DC current while the LED is being driven a drive current; and

a drive circuit that provides said drive current, said drive circuit responsive to the memristor resistance value and varying the drive current to said LED based on the resistance of said memristor.

35. The solid state lighting device of claim 34, wherein the DC current received by said memristor is proportional to said drive current.

36. The solid state lighting device of claim 34, wherein the resistance of said memristor does not directly cause a change in said drive current.

37. The solid state lighting device of claim 34, wherein said memristor is arranged remote to sand LED.