LED dimming circuit

• US 8,040,078 B1
• Filed: 06/09/2009
• Issued: 10/18/2011
• Est. Priority Date: 06/09/2009
• Status: Expired due to Fees

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Jamasbi, Khosrow, Knoble, David W.
• Primary Examiner(s): Ismail; Shawki
• Assistant Examiner(s): WHITE, DYLAN C
• Application Number:
  US12/481,299
• Time in Patent Office: 861 Days
• Field of Search: 315/129, 315/134, 315/149, 315/200.R, 315/246, 315/291, 315/292, 315/297, 315/307, 315/308, 315/DIG.4, 323/905
• US Class Current: 315/291
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
• CPC Class Codes: Y10S 323/905 Lamp dimmer structure

Abstract

A LED dimming circuit is provided. The LED dimming circuit has an LED driver, an LED dimmer, and at least one LED light source. A resistor is connected between a dimming control output of the LED dimmer and dimming control input of the LED dimmer. The LED dimming circuit may optionally include a fluorescent slide dimmer. The fluorescent slide dimmer may have a first connection to the dimming control input of the LED dimmer and a second connection to a circuit common of the LED dimmer. A method of providing an LED dimming circuit for dimming at least one LED light source using a fluorescent dimmer is also provided.

Claims

1. An LED dimming circuit, comprising:

at least one LED light source;

an LED driver configured to receive an AC signal and produce a first DC signal;

an LED dimmer connected to said LED driver and said at least one LED light source, said LED dimmer having a dimming control input, a dimming control output, a circuit common, and a variable LED dimmer output;

wherein said LED dimmer receives said first DC signal from said LED driver and outputs said variable LED dimmer output to said at least one LED light source to power said LED light source at a desired light output level, and wherein said variable LED dimmer output is dependent on at least one characteristic of a signal received by said dimming control input;

a fluorescent dimmer having a first connection to said dimming control input and a second connection to said circuit common;

a resistor connected between said dimming control output and said first connection;

wherein adjustment of said fluorescent dimmer varies said at least one characteristic of said signal received by said dimming control input.

2. The LED dimming circuit of claim 1, wherein said resistor has a resistance between 10 kΩ

and 20 kΩ

.

3. The LED dimming circuit of claim 2, wherein said dimming control output is a 0 to 10 volt output.

4. The LED dimming circuit of claim 3, wherein said variable LED dimmer output is selectively pulse width modulated.

5. The LED dimming circuit of claim 3, wherein said fluorescent dimmer is a 0-10 Volt fluorescent slide dimmer.

6. The LED dimming circuit of claim 3, wherein said desired light output level of said LED light source ranges from a full light output level to an approximately twenty three percent light output level.

7. The LED dimming circuit of claim 3, wherein said fluorescent slide dimmer is connected to said AC signal and said LED driver;

and wherein said fluorescent slide dimmer may selectively remove said AC signal from said LED driver.

8. The LED dimming circuit of claim 1, wherein said resistor has a resistance of approximately 15 kΩ

.

9. An LED dimming circuit for use with a fluorescent dimmer, comprising:

an LED driver configured to receive an AC signal and produce a first DC signal;

an LED dimmer connected to said LED driver and connectable to at least one LED light source, said LED dimmer having a dimming control input, a dimming control output, a circuit common, and a variable LED dimmer output;

wherein said LED dimmer receives said first DC signal from said LED driver and outputs said variable LED dimmer output; and

wherein said variable LED dimmer output is dependent on at least one characteristic of a signal received by said dimming control input;

a resistor coupled between said dimming control output and said dimming control input;

wherein said resistor has a resistance between 10 kΩ and

20 kΩ

.

10. The LED dimming circuit of claim 9, wherein said resistor has a resistance of approximately 15 kΩ

.

11. The LED dimming circuit of claim 10, wherein said dimming control output is a 0 to 10 volt output.

12. The LED dimming circuit of claim 9, wherein said variable LED dimmer output is selectively pulse width modulated.

13. The LED dimming circuit of claim 9, wherein said LED driver dimmer and said LED dimmer are integrated into a single component part.

14. A method of providing an LED dimming circuit for dimming at least one LED light source using a fluorescent dimmer, comprising:

providing an LED driver electrically coupled to an LED dimmer;

wherein said LED driver is configured to receive an AC signal and produce a first DC signal;

wherein said LED dimmer has a dimming control input, a dimming control output, a circuit common, and a variable LED dimmer output;

wherein said LED dimmer is configured to receive said first DC signal from said LED driver and output said variable LED dimmer output to at least one LED light source to power said LED light source at a desired light output level;

wherein said variable LED dimmer output is dependent on at least one characteristic of a signal received by said dimming control input;

providing a resistor connected between said dimming control output of said LED dimmer and said dimming control input of said LED dimmer;

instructing a user to couple a first fluorescent dimmer connection to said dimming control input of said LED dimmer and a second fluorescent dimmer connection to said circuit common of said LED dimmer.

15. The method of claim 14, wherein said resistor has a resistance between 10 kΩ

and 20 kΩ

.

16. The method of claim 14, wherein said resistor has a resistance of approximately 15 kΩ

.

17. The LED dimming circuit of claim 16, wherein said variable LED dimmer output is selectively pulse width modulated.