SYSTEM AND METHOD FOR CONTROLLING LED SEGMENTS TO PROVIDE LIGHTING EFFECTS

• US 20130278163A1
• Filed: 03/15/2013
• Published: 10/24/2013
• Est. Priority Date: 04/23/2012
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: Rodriguez, Yan, Bruce, Michael, Hand, Mark Anthony, Sieczkowski, Philip
• Granted Patent: US 9,456,478 B2
• Time in Patent Office: Days
• US Class Current: 315/201
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05B 45/31 Phase-control circuits
• CPC Class Codes: H05B 45/3574 Emulating the electrical or functional characteristics of incandescent lamps
• CPC Class Codes: H05B 45/48 having LEDs organised in strings and incorporating parallel shunting devices

Abstract

A single board light engine includes an AC to AC step driver that selectively powers multiple LED segments by controlling tap points between the LED segments as the input voltage goes from zero crossover to maximum voltage and returns to zero crossover. The step driver may power a first LED segment, a second LED segment, both the first and second LED segments, or none of the LED segments depending upon the input voltage level. The LEDs within an LED segment may share a characteristic that differs from a characteristic shared by LEDs in another segment, which allows the LED fixture to provide a variety of lighting effects.

Claims

1. A single board light engine comprising:

an LED step driver having an input connected to rectified line voltage;

a first LED segment comprising a first plurality of LEDs, wherein the first LED segment has a first characteristic;

a second LED segment comprising a second plurality of LEDs, wherein the second LED segment has a second characteristic, which is different than the first characteristic;

a first tap point between a last LED of the first LED segment and a first LED of the second LED segment; and

a second tap point after a last LED of the second LED segment,

wherein the LED step driver controls the first tap point and the second tap point to drive only the first LED segment when the input to the LED step driver is between a first voltage level and a second voltage level and to drive the first LED segment and the second LED segment when the input to the LED step driver is above the second voltage level, wherein the second voltage level is higher than the first voltage level, and

wherein a first lighting effect based on the first characteristic is produced by the light engine between the first voltage level and the second voltage level, and a second lighting effect based on a combination of the first characteristic and the second characteristic is produced by the light engine above the second voltage level.

2. The single board light engine of claim 1, wherein the first characteristic is a first location on the board, the second characteristic is a second location on the board, and the second LED segment at least partially surrounds the first LED segment, and wherein the first lighting effect is center brightness and the second lighting effect is brightness extended outwards from center.

3. The single board light engine of claim 1, wherein the first characteristic is a first color and the second characteristic is a second color, and wherein the first lighting effect is the first color and the second lighting effect is a blend of the first color and the second color.

4. The single board light engine of claim 1, wherein the first characteristic is a first color temperature, the second characteristic is a second color temperature, and the first color temperature is lower than the second color temperature, and wherein the first lighting effect is the first color temperature and the second lighting effect is a color temperature between the first color temperature and the second color temperature.

5. The single board light engine of claim 1, wherein the first characteristic is a first light distribution and the second characteristic is a second light distribution, further comprising:

a first optical element that is associated with the first LED segment and provides the first light distribution; and

a second optical element that is associated with the second LED segment and provides the second light distribution, and

wherein the first lighting effect is the first light distribution and the second lighting effect is a light distribution based on a combination of the first light distribution and the second light distribution.

6. The single board light engine of claim 1, wherein the first plurality of LEDs include discrete LEDs.

7. The single board light engine of claim 1, wherein the first plurality of LEDs include chip-on-board (COB) LEDs.

8. A single board light engine comprising:

a rectifier for generating rectified line voltage;

an LED step driver having an input connected to the rectified line voltage;

a first LED segment comprising a first plurality of LEDs, wherein the first LED segment has a first characteristic;

a second LED segment comprising a second plurality of LEDs, wherein the second LED segment has a second characteristic, which is different than the first characteristic;

a first tap point between a last LED of the first LED segment and a first LED of the second LED segment;

a second tap point after a last LED of the second LED segment;

wherein the LED step driver controls the first tap point and the second tap point to drive only the first LED segment when the input to the LED step driver is between a first voltage level and a second voltage level and to drive the first LED segment and the second LED segment when the input to the LED step driver is above the second voltage level, wherein the second voltage level is higher than the first voltage level.

9. The single board light engine of claim 8, wherein the first characteristic is a first location on the board and the second characteristic is a second location on the board, and the second LED segment at least partially surrounds the first LED segment.

10. The single board light engine of claim 8, wherein the first characteristic is a first color and the second characteristic is a second color.

11. The single board light engine of claim 8, wherein the first characteristic is a first color temperature and the second characteristic is a second color temperature, and the first color temperature is lower than the second color temperature.

12. The single board light engine of claim 8, wherein the first characteristic is a first light distribution and the second characteristic is a second light distribution further comprising:

a first optical element that is associated with the first LED segment and provides the first light distribution; and

a second optical element that is associated with the second LED segment and provides the second light distribution.

13. The single board light engine of claim 8, wherein the first plurality of LEDs include discrete LEDs.

14. The single board light engine of claim 8, wherein the first plurality of LEDs include chip-on-board (COB) LEDs.

15. The single board light engine of claim 8, wherein the board is part of a downlight.

16. The single board light engine of claim 8, further comprising:

a second single board light engine having a second LED step driver,

wherein the input to the LED step driver on the single board light engine and an input to the second LED step driver on the second single board light engine is further controlled by a multi-position switch, and

wherein when the switch is in a first position, the single board light engine receives a full cycle of the line voltage and the second single board light engine is not powered, when the switch is in a second position, the single board light engine receives a first half cycle of the line voltage and the second single board light engine receives a second half cycle of the line voltage, and when the switch is in a third position, the second single board light engine receives a full cycle of the line voltage and the single board light engine is not powered.

17. A method of controlling a plurality of LED segments, comprising:

determining an input voltage level;

if the input voltage level is below a first voltage level, then controlling the LED segments so that none of the LED segments are powered;

if the input voltage level is between a first voltage level and a second voltage level, then controlling the LED segments so that only a first LED segment is powered;

if the input voltage level is above the second voltage level, then controlling the LED segments so that the first LED segment and a second LED segment are powered;

wherein the first LED segment has a first characteristic, the second LED segment has a second characteristic, and the first characteristic is different than the first characteristic, and wherein a first lighting effect based on the first characteristic is provided at the first voltage level and a second lighting effect based on a combination of the first characteristic and the second characteristic is provided at the second voltage level.

18. The method of claim 17, wherein the first characteristic is a first location on the board, the second characteristic is a second location on the board, and the second LED segment at least partially surrounds the first LED segment, and wherein the first lighting effect is center brightness and the second lighting effect is brightness extended outwards from center.

19. The method of claim 17, wherein the first characteristic is a first color and the second characteristic is a second color, and wherein the first lighting effect is the first color and the second lighting effect is a blend of the first color and the second color.

20. The method of claim 17, wherein the first characteristic is a first color temperature, the second characteristic is a second color temperature, and the first color temperature is lower than the second color temperature, and wherein the first lighting effect is a first color temperature and the second lighting effect is a color temperature between the first color temperature and the second color temperature.

21. The method of claim 17, wherein the first characteristic is a first light distribution and the second characteristic is a second light distribution, and wherein the first lighting effect is the first light distribution and the second lighting effect is a light distribution based on a combination of the first light distribution and the second light distribution.