Luminaire with long chains of lower power LEDs and multiple on-board LED drivers
A luminaire may include an input connection that receives AC line voltage, one or more chains of LEDs, and one or more drivers for driving each chain of LEDs, all within a housing, which may be in the form of a canopy. Each chain of LEDs may contain at least 36 LEDs connected in series. Each LED may have a power rating of no more than 1 watt and may be oriented to direct light outside of the housing when illuminated. Each driver may receive power that is extracted from AC line voltage connected to the input connection and provide one or more outputs that drive at least one of the chains of LEDs.
1. A luminaire comprising: a housing; an input connection within the housing that receives AC line voltage; multiple chains of LEDs within the housing, each chain containing at least 36 LEDs connected in series, and each LED having a power rating of no more than 1 watt and oriented to direct light outside of the housing when illuminated; and multiple LED drivers within the housing that receive power that is extracted from AC line voltage connected to the input connection and provide one or more outputs that drive each of the LEDs within the multiple chains of LEDs.
2. The luminaire of claim 1 wherein:
each chain of LEDs is comprised of multiple sub-chains of LEDs connected in series, each sub-chain containing multiple LEDs in series; and
each of the LED drivers provide a separate output that drives at least one of the chains of LEDs at each of the junctions between each of its sub-chains in a stepped sequence that is a function of the level of voltage of the power that is received by LED driver.
3. The luminaire of claim 2 wherein at least one sub-chain within each chain includes at least 12 LEDs.
4. The luminaire of claim 3 wherein no sub-chain within each chain includes less than 6 LEDs.
5. The luminaire of claim 2 wherein the outputs of at least two of the LED drivers are connected in parallel.
6. The luminaire of claim 2 wherein the outputs of at least one of the LED drivers is connected to one of the chains of LEDs and the outputs of at least one other of the LED drivers is connected to another of the chains of LEDs.
7. The luminaire of claim 1 wherein the input connection, the multiple chains of LEDs, and the multiple LED drivers are all on a single printed circuit board.
8. The luminaire of claim 1 wherein each chain has at least 48 LEDs.
9. The luminaire of claim 1 wherein the power rating of each LED is no more than 0.6 watt.
10. The luminaire of claim 1 wherein the housing forms a canopy light.
11. A luminaire comprising:
a housing;
an input connection within the housing that receives AC line voltage;
at least one chain of LEDs within the housing containing at least 36 LEDs connected in series, each LED having a power rating of no more than 1 watt and oriented to direct light outside of the housing when illuminated; and
at least one LED driver within the housing that receives power that is extracted from AC line voltage connected to the input connection and provides one or more outputs that drive the chain of LEDs.
12. The luminaire of claim 11 wherein:
the chain of LEDs is comprised of multiple sub-chains of LEDs connected in series, each sub-chain containing multiple LEDs in series; and
the at least one driver provides a separate output that drives the at least one chain of LEDs at each of the junctions between each of its sub-chains in a stepped sequence that is a function of the level of voltage of the power that is received by LED driver.
13. The luminaire of claim 12 wherein at least one sub-chain within the at least one chain includes at least 12 LEDs.
14. The luminaire of claim 13 wherein no sub-chain within the at least one chain includes less than 6 LEDs.
15. The luminaire of claim 11 wherein the at least one driver includes at least two drivers whose outputs are connected in parallel.
16. The luminaire of claim 11 wherein the input connection, at least one chain of LEDs, and the at least one driver are all on a single printed circuit board.
17. The luminaire of claim 11 wherein the at least one chain has at least 48 LEDs.
18. The luminaire of claim 11 wherein the power rating of each LED is no more than 0.6 watt.
19. The luminaire of claim 11 wherein the housing forms a canopy light.
20. A luminaire comprising: a housing; an input connection within the housing that receives AC line voltage; at least one chain of LEDs within the housing containing multiple LEDs connected in series, each LED oriented to direct light outside of the housing when illuminated; and multiple LED drivers within the housing that receive power that is extracted from AC line voltage connected to the input connection and provide one or more outputs that drive each of the LEDs within the at least one chain of LEDs.
21. The luminaire of claim 20 wherein:
the at least one chain of LEDs is comprised of multiple sub-chains of LEDs connected in series, each sub-chain containing multiple LEDs in series; and
each of the drivers provides a separate output that drives the at least one chain of LEDs at each of the junctions between each of its sub-chains in a stepped sequence that is a function of the level of voltage of the power that is received by LED drivers.
22. The luminaire of claim 21 wherein the outputs of at least two of the drivers are connected in parallel.
23. The luminaire of claim 21 wherein the outputs of at least two of the drivers are connected to different chains of LEDs.
24. The luminaire of claim 20 wherein the input connection, the at least one chain of LEDs, and the multiple LED drivers are all on a single printed circuit board.
25. The luminaire of claim 20 wherein the housing forms a canopy light.
26. A luminaire comprising: a housing; an input connection within the housing that receives AC line voltage; a chain of LEDs within the housing containing multiple LEDs connected in series, each oriented to direct light outside of the housing when illuminated; and multiple LED drivers within the housing, each of which receive power that is extracted from AC line voltage connected to the input connection and provide an output that drives each of the LEDs within the chain of LEDs, each of the outputs being connected in parallel.
27. The luminaire of claim 26 wherein each LED driver provides multiple stepped outputs at different step levels and wherein each stepped output is connected in parallel with all of the other stepped outputs from the other LED drivers at the same step level.