Circuit boards for LED-based light fixtures
View Patent ↗A light fixture having master circuit boards and one or more LED circuit boards connectable in various alternative combinations for light fixtures having alternative lengths, the master board including a switch and AC-DC rectifier and the LED boards including linear AC drivers and one or more LED arrays, the switch on the master board controlling the linear AC drivers on the LED board or boards.
1. A light fixture comprising:
a master board having an input to receive AC power, an AC-DC rectifier coupled to receive AC power and generate DC power, and a power output connector to supply DC power; and
a first light-emitting diode (LED) board having a first end and a second end, and coupled to receive the DC power, the first LED board comprising:
a first LED array;
a first linear AC driver coupled to receive the DC power and drive a current through the first LED array;
a power input connector connectable to the power output connector and connected to the first linear AC driver;
a first power input/output connector positioned at the first end, and connected to the power input connector; and
a second power input/output connector positioned at the second end, and connected to the power input connector and the first power input/output connector.
2. The light fixture of claim 1 further comprising a plurality of LED boards each comprising at least one linear AC driver driving at least one LED, wherein each of the plurality of LED boards are connected in parallel to the first LED board.
3. The light fixture of claim 2 wherein the plurality of LED boards have a ladder spatial arrangement.
4. The light fixture of claim 2 wherein the first LED board has a shape consisting of one of round, square, hexagon, and octagon.
5. The light fixture of claim 1 further comprising:
a second LED board coupled to receive DC power comprising:
a second LED array; and
a second linear AC driver coupled to receive the DC power and drive current through the second LED array.
6. The light fixture of claim 5 wherein the first linear AC driver is a constant current regulator and the second linear AC driver is a constant current regulator.
7. The light fixture of claim 5 wherein the first linear AC driver is an application specific integrated circuit (ASIC) and the second linear AC driver is an ASIC.
8. A light fixture comprising:
a master board having an input to receive AC power, a switch, an AC-DC rectifier, and a power output connector, the master board configured to receive the AC power and drive DC power on a selected one of a plurality of channels depending on the switch; and
a first light-emitting diode (LED) board coupled to receive DC power on any of the plurality of channels, the first LED board comprising:
a first LED array;
a plurality of linear AC drivers each coupled to receive the DC power on one of the plurality of channels, wherein the first LED array is coupled to receive current from a first linear AC driver of the plurality of linear AC drivers;
a power input connector connectable to the power output connector and connected to the plurality of linear AC drivers;
a first power input/output connector positioned at a first end of the first LED board, and connected to the power input connector; and
a second power input/output connector positioned at a second end of the first LED board, and connected to the power input connector and the first power input/output connector.
9. The light fixture of claim 8 wherein the LED board has a shape consisting of one of round, square, hexagon, and octagon.
10. The light fixture of claim 8 wherein the first LED array is coupled to receive current from at least two of the plurality of linear AC drivers, the first linear AC driver of the plurality of linear AC drivers is configured to generate more current than a second linear AC driver of the plurality of linear AC drivers.
11. The light fixture of claim 8 wherein the AC-DC rectifier is coupled to receive AC power and drive DC power and the switch is coupled to receive the DC power and drive the DC power on a selected one of the plurality of channels depending on the switch.
12. The light fixture of claim 8 wherein the switch is coupled to receive the AC power and drive the AC power on a selected one of a plurality on nodes depending on the switch, and a plurality of AC-DC rectifiers each coupled to receive AC power on one of the plurality of nodes and drive DC power on one of the plurality of channels.
13. The light fixture of claim 8 wherein the first LED board further comprises:
a second LED array wherein the second LED array is coupled to receive current from a second linear AC driver of the plurality of linear AC drivers.
14. The light fixture of claim 8 further comprising a sensor configured to detect a condition, wherein the first LED array is conditionally coupled to receive current from a first linear AC driver of the plurality of linear AC drivers depending on the condition detected by the sensor.
15. The light fixture of claim 14 wherein the condition detected is at least one of motion, light and sound.
16. The light fixture of claim 8 further comprising a wireless control interface configured to detect and receive a wireless control signal, wherein the first LED array is conditionally coupled to receive current from a first linear AC driver of the plurality of linear AC drivers depending on the wireless control signal.
17. The light fixture of claim 8 further comprising a second LED array wherein the first LED array is coupled to receive current from each of the plurality of linear AC drivers coupled to a first channel of the plurality of channels and the second LED array is coupled to receive current from each of the plurality of linear AC drivers coupled to a second channel of the plurality of channels.
18. The light fixture of claim 17 where the first LED array generates light having a different color than the second LED array.
19. The light fixture of claim 17 where the first LED array generates light having a different color rendering index (CRI) than the second LED array.
20. The light fixture of claim 17 where the first LED array generates light having a different correlated color temperature (CCT) than the second LED array.
21. The light fixture of claim 8 wherein each of the plurality of linear AC drivers is a constant current regulator.
22. The light fixture of claim 8 wherein each of the plurality of linear AC drivers is an application specific integrated circuit (ASIC).