Circuitry for warm dim lighting
A method of dimming an LED luminaire and a dimmable LED luminaire includes two pluralities of LEDs. The first plurality emits electromagnetic radiation at a first frequency to react with a remote phosphor and provide a phosphor illumination. The second plurality of LEDs are phosphor LEDs that emit phosphor electromagnetic radiation at a second frequency to react with the remote phosphor and provide double-phosphor illumination. The phosphors and LEDs are configured to produce specific color points when the LEDs are at full power and at full dim. When the luminaire receives a dimming signal, the first plurality of LEDs dim the phosphor illumination over a majority of the luminaire's illumination range, but the second plurality of LEDs continue to receive constant current and provide undimmed double-phosphor illumination over the majority of the luminaire's illumination range.
1. A power supply for powering a first plurality of LEDs via a first output and a second plurality of LEDs via a second output, comprising:
an input portion accepting an electrical power signal from an external source;
a dimming portion;
a fixed power supply portion generating the second output an fixed electrical signal that will cause the second plurality of LEDs to have a fixed illumination over a preselected range responsive to changes in a dimming signal from the dimming portion; and
a variable power supply portion generating at the first output a variable electrical signal that will cause the first plurality of LEDs to have a variable illumination responsive to changes in the signal from the dimming portion while the fixed power supply portion generates at the second output the fixed electrical signal.
2. The power supply according to claim 1 , wherein the variable power supply portion generates a variable electrical signal that varies current provided to the first output over a range of at least 75% to 25% responsive to changes in the signal from the dimming portion while the fixed power supply portion generates at the second output a fixed current electrical signal.
3. The power supply according to claim 1 , wherein the variable power supply portion generates a variable electrical signal that varies current provided to the first output over a range of at least 99% to 15% responsive to changes in the signal from the dimming portion while the fixed power supply portion generates at the second output a fixed current electrical signal.
4. The power supply according to claim 1 , wherein the dimming portion determines that the variable electrical signal at the first output is to be changed while the fixed current electrical signal at the second output using at least one of the following characteristics of the electrical power signal from the external source:
(a) detecting that the electrical power signal has less than nominal amplitude;
(b) detecting that the electrical power signal has been forward phase altered (forward phase control) for forward phase dimming;
(c) detecting that the electrical power signal has been reverse phase altered (reverse phase control) for reverse phase dimming; and
(d) detecting that the electrical power signal has been otherwise altered to provide something other than the nominal power signal.
5. The power supply according to claim 2 , wherein the dimming portion determines that the variable electrical signal at the first output is to be changed while the fixed current electrical signal at the second output using at least one of the following characteristics of the electrical power signal from the external source:
(a) detecting that the electrical power signal has less than nominal amplitude;
(b) detecting that the electrical power signal has been forward phase altered (forward phase control) for forward phase dimming;
(c) detecting that the electrical power signal has been reverse phase altered (reverse phase control) for reverse phase dimming; and
(d) detecting that the electrical power signal has been otherwise altered to provide something other than the nominal power signal.
6. The power supply according to claim 3 , wherein the dimming portion determines that the variable electrical signal at the first output is to be changed while the fixed current electrical signal at the second output using at least one of the following characteristics of the electrical power signal from the external source:
(a) detecting that the electrical power signal has less than nominal amplitude;
(b) detecting that the electrical power signal has been forward phase altered (forward phase control) for forward phase dimming;
(c) detecting that the electrical power signal has been reverse phase altered (reverse phase control) for reverse phase dimming; and
(d) detecting that the electrical power signal has been otherwise altered to provide something other than the nominal power signal.
7. The power supply according to claim 1 , wherein the dimming portion determines that the variable electrical signal at the first output is to be changed via a received dimming signal that is other than a modified electrical power signal from the external source.
8. The power supply according to claim 1 , wherein the power supply further comprises a wireless receiver and further wherein the dimming portion determines that the variable electrical signal at the first output is to be changed via a received wireless dimming signal.
9. The power supply according to claim 2 , wherein the power supply further comprises a wireless receiver and further wherein the dimming portion determines that the variable electrical signal at the first output is to be changed via a received wireless dimming signal.
10. The power supply according to claim 3 , wherein the power supply further comprises a wireless receiver and further wherein the dimming portion determines that the variable electrical signal at the first output is to be changed via a received wireless dimming signal.
11. The power supply according to claim 1 , wherein the fixed power supply portion generates the fixed electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
12. The power supply according to claim 2 , wherein the fixed power supply portion generates the fixed electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
13. The power supply according to claim 3 , wherein the fixed power supply portion generates the fixed electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
14. The power supply according to claim 4 , wherein the fixed power supply portion generates the fixed electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
15. The power supply according to claim 7 , wherein the fixed power supply portion generates the fixed electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
16. The power supply according to claim 1 , wherein the fixed power supply portion generates a constant current electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
17. The power supply according to claim 2 , wherein the fixed power supply portion generates a constant current electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
18. The power supply according to claim 3 , wherein the fixed power supply portion generates a constant current electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
19. The power supply according to claim 4 , wherein the fixed power supply portion generates a constant current electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.
20. The power supply according to claim 7 , wherein the fixed power supply portion generates a constant current electrical signal at the second output responsive to changes in a dimming signal from the dimming portion until a point where the variable power supply portion turns off the variable electrical signal at the first output, at which time the fixed power supply portion turns off the fixed electrical signal at the second output.