Downlight Reference Design

Cree® XLamp® XM-L LED
6-Inch Downlight Reference Design
Table of Contents
Introduction
Introduction....................................................................................1
This application note details the design of a 6-inch downlight
Design approach/objectives.........................................................2
using Cree’s XLamp® XM-L LED, a single die, high-flux
The 6-step methodology................................................................2
component optimized for very high-lumen applications such
1. Define lighting requirements..............................................2
as indoor commercial, high-bay and roadway lights. The XM-L
2. Define design goals............................................................4
offers industry-leading performance and reliability.
3. Estimate efficiencies of the optical, thermal & electrical
systems...............................................................................4
4. Calculate the number of LEDs ..........................................7
5. Consider all design possibilities........................................7
6. Complete the final steps....................................................8
Conclusion....................................................................................14
www.cree.com/Xlamp
Bill of materials............................................................................15
CLD-AP93 rev 0C
Application Note
Six-inch downlights are the industry standard indoors and
outdoors in both residential and commercial applications such
as soffits and ceilings, where a wide beam pattern is desirable.
Although typical light output ranges from 500 to 2000 lumens,
high-ceiling applications require even higher light levels. The
high flux and efficacy offered by the XLamp XM-L LED make it a
strong candidate for use in such a 6-inch downlight.
Reliance on any of the information provided in this Application Note is at the user’s sole risk. Cree and its affiliates make no warranties or representations about, nor assume
any liability with respect to, the information in this document or any LED-based lamp or luminaire made in accordance with this reference design, including without limitation
that the lamps or luminaires will not infringe the intellectual property rights of Cree or a third party. Luminaire manufacturers who base product designs in whole or part on
any Cree Application Note or Reference Design are solely responsible for the compliance of their products with all applicable laws and industry requirements.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are
registered trademarks and the Cree logo is a trademark of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection
Agency. Other trademarks, product, and company names are the property of their respective owners and do not imply specific product and/or vendor
endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information,
please contact Cree Sales at [email protected]
Cree, Inc.
4600 Silicon Drive
Durham, NC 27703
USA Tel: +1.919.313.5300
1
XLamp ® XM-L LED 6-inch downlight Reference Design
Design approach/objectives
In the “LED Luminaire Design Guide” Cree advocates a 6-step framework for creating LED luminaires. All Cree reference designs use this
framework, and the design guide’s summary table is reproduced below.
Table 1: Cree 6-step framework
Step
Explanation
1. Define lighting requirements
•
The design goals can be based either on an existing fixture or on the application’s lighting requirements.
2. Define design goals
•
•
Specify design goals, which will be based on the application’s lighting requirements.
Specify any other goals that will influence the design, such as special optical or environmental
requirements.
3. Estimate efficiencies of the optical, thermal &
electrical systems
•
•
•
Design goals will place constraints on the optical, thermal and electrical systems.
Good estimations of efficiencies of each system can be made based on these constraints.
The combination of lighting goals and system efficiencies will drive the number of LEDs needed in the
luminaire.
4. Calculate the number of LEDs needed
•
Based on the design goals and estimated losses, the designer can calculate the number of LEDs to meet
the design goals.
5. Consider all design possibilities and choose
the best
•
•
With any design, there are many ways to achieve the goals.
LED lighting is a new field; assumptions that work for conventional lighting sources may not apply.
6. Complete final steps
•
•
•
•
•
Complete circuit board layout.
Test design choices by building a prototype luminaire.
Make sure the design achieves all the design goals.
Use the prototype to further refine the luminaire design.
Record observations and ideas for improvement.
The 6-step methodology
The goal of the design is an LED-based downlight that shows the performance available from the XLamp XM-L LED.
1. Define lighting requirements
Table 2shows a ranked list of desirable characteristics to address in a downlight reference design.
Table 2: Some ranked design criteria for an LED downlight
Importance
Critical
Characteristics
Units
Luminous flux (steady-state)
lumens (lm)
Efficacy
lumens per watt (lm/W)
Luminous distribution
Color uniformity
Form factor
Important
Price
$
Lifetime
hours
Operating temperatures
°C
Operating humidity
% relative humidity
CCT
K
CRI
100-point scale
Manufacturability
Ease of installation
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
2
XLamp ® XM-L LED 6-inch downlight Reference Design
Table 3 and Table 4 summarize the ENERGY STAR® requirements for luminaires.1
Table 3: ENERGY STAR luminous efficacy, output and zonal lumen-density requirements
ENERGY STAR REQUIREMENTS
Luminaire Type
Luminaire Efficacy (Initial)
Downlights:
•
recessed
•
surface
•
pendant
•
SSL downlight retrofits
42 lm/W
Luminaire Minimum Light
Output (Initial)
≤ 4.5” aperture: 345 lumens
> 4.5” aperture: 575 lumens
Luminaire Zonal Lumen
Density Requirement
Luminaire shall deliver a minimum of
75% of total initial lumens within the
0-60° zone (axially symmetric about the
nadir)
Table 4: ENERGY STAR luminaire requirements
Characteristic
Requirements
Light source life requirements: all
luminaires
The LED package(s) / LED module(s) / LED array(s), including those incorporated into LED light engines or GU24 based integrated
LED lamps, shall meet the following L70 lumen maintenance life values (refer to Lumen Maintenance Requirements in the next
section):
•
•
•
25,000 hours for residential grade indoor luminaires
35,000 hours for residential grade outdoor luminaires
35,000 hours for commercial grade luminaires
Lumen maintenance life projection claims in excess of the above requirements shall be substantiated with a TM-21 lumen
maintenance life projection report.
Lumen maintenance requirements:
directional and non-directional
luminaires
The LED package(s) / module(s) / array(s), including those incorporated into LED light engines or GU24 based integrated LED
lamps, shall meet the following
•
•
•
L70(6k) rated lumen maintenance life values, in situ:
L70(6k) ≥ 25,000 hours for residential indoor
L70(6k) ≥ 35,000 hours for residential outdoor, or commercial
Compliance with the above shall be documented with a TM-21 lumen maintenance life projection report as detailed in TM-21,
section 7. The report shall be generated using data from the LM-80 test report for the employed LED package/module/array model
(“device”), the forward drive current applied to each device, and the in situ TMPLED temperature of the hottest LED in the luminaire. In
addition to LM-80 reporting requirements, the following information shall be reported:
•
•
•
•
•
•
sampling method and sample size (per LM-80 section 4.3)
test results for each TS and drive current combination
description of device including model number and whether device is an LED package, module or array (see Definitions)
ANSI target, and calculated CCT value(s) for each device in sample set
Δ u’v’ chromaticity shift value on the CIE 1976 diagram for each device in sample set
a detailed rationale, with supporting data, for application of results to other devices (e.g. LED packages with other CCTs)
Access to the TMPLED for the hottest LED may be accomplished via a minimally sized hole in the luminaire housing, tightly resealed
with a suitable sealant if created for purposes of testing.
All thermocouple attachments and intrusions to luminaire housing shall be photographed.
CCT requirements: all indoor
luminaires
The luminaire (directional luminaires), or replaceable LED light engine or GU24 based integrated LED lamp (non-directional
luminaires) shall have one of the following nominal CCTs:
•
•
•
•
•
2700 Kelvin
3000 Kelvin
3500 Kelvin
4000 Kelvin
5000 Kelvin (commercial only)
The luminaire, LED light engine or GU24 based integrated LED lamp shall also fall within the corresponding 7-step chromaticity
quadrangles as defined in ANSI/NEMA/ANSLG C78.377-2008.
Color rendering requirements: all
indoor luminaires
The luminaire (directional luminaires), or replaceable LED light engine or GU24 based integrated LED lamp (non-directional
luminaires) shall meet or exceed Ra ≥ 80.
Color angular uniformity
requirements: directional solid state
indoor luminaires
Throughout the zonal lumen density angles detailed above, and five degrees beyond, the variation of chromaticity shall be within
0.004 from the weighted average point on the CIE 1976 (u’,v’) diagram.
1
ENERGY STAR Program Requirements, Product Specification for Luminaires (Light Fixtures), Eligibility Criteria, Version 1.1
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
3
XLamp ® XM-L LED 6-inch downlight Reference Design
Characteristic
Requirements
Color maintenance requirements:
solid state indoor luminaires only
The change of chromaticity over the first 6,000 hours of luminaire operation shall be within 0.007 on the CIE 1976 (u’,v’) diagram, as
demonstrated by either:
•
•
•
the IES LM-80 test report for the employed LED package/array/module model, or
as demonstrated by a comparison of luminaire chromaticity data in LM-79 reports at zero and 6,000 hours, or
as demonstrated by a comparison of LED light engine or GU24 based integrated LED lamp chromaticity data in LM-82 reports
at zero and 6,000 hours.
Source start time requirement:
directional and non-directional
luminaires
Light source shall remain continuously illuminated within one second of application of electrical power.
Source run-up time requirements:
directional and non-directional
luminaires
Light source shall reach 90% of stabilized lumen output within one minute of application of electrical power.
Power factor requirements:
directional and non-directional
luminaires
Total luminaire input power less than or equal to 5 watts: PF ≥ 0.5
Transient protection requirements:
all luminaires
Ballast or driver shall comply with ANSI/IEEE C62.41.1-2002 and ANSI/IEEE C62.41.2-2002, Class A operation. The line transient
shall consist of seven strikes of a 100 kHz ring wave, 2.5 kV level, for both common mode and differential mode.
Operating frequency requirements:
directional and non-directional
luminaires
Frequency ≥ 120 Hz
Noise requirements: directional and
non-directional luminaires
All ballasts & drivers used within the luminaire shall have a Class A sound rating.
Electromagnetic and radio frequency
interference requirements:
directional and non-directional
luminaires
Power supplies and/or drivers shall meet FCC requirements:
Total luminaire input power greater than 5 watts:
Residential: PF ≥ 0.7
Commercial: PF ≥ 0.9
Note: This performance characteristic addresses problems with visible flicker due to low frequency operation and applies to steadystate as well as dimmed operation. Dimming operation shall meet the requirement at all light output levels.
Ballasts and drivers are recommended to be installed in the luminaire in such a way that in operation, the luminaire will not emit
sound exceeding a measured level of 24 BA.
•
•
Class A for power supplies or drivers that are marketed for use in a commercial, industrial or business environment, exclusive
of a device which is marketed for use by the general public or is intended to be used in the home.
Class B for power supplies or drivers that are marketed for use in a residential environment notwithstanding use in
commercial, business and industrial environments.
2. Define design goals
Table 5 shows the design goals for this project.
Table 5: Design goals
Characteristic
Light output
Power
Unit
Minimum Goal
Target Goal
lm
3000
> 3000
W
50
< 50
Luminaire efficacy
lm/W
60
65
Lifetime
hours
50,000
50,000
CCT
K
3000
3000
CRI
100-point scale
80
> 80
%
90
> 90
Power factor
3. Estimate efficiencies of the optical, thermal & electrical systems
We used Cree’s Product Characterization Tool (PCT) tool to determine the drive current for the design.
For the 3000-lumen target, we estimated 92% optical efficiency and 85% driver efficiency. We also estimated a solder point temperature
of 55 °C.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
4
XLamp ® XM-L LED 6-inch downlight Reference Design
LED System Comparison Rep
1
System:
3,000
Target Lumens :
90
Optical Efficiency:
LED 1
LED 2
$
Price
SYS lm tot SYS # LED SYS lm/W
0.350
0.400
0.450
0.500
0.550
0.600
0.650
0.700
0.750
0.800
0.850
0.900
0.950
1.000
1.100
1.200
1.300
1.400
1.500
1.600
1.700
1.800
1.900
2.000
3032.2
3018.7
3017.4
3069.4
3066.3
3009.8
3071.5
3106.1
3113.9
3095.4
3051.2
3211
3128
3020.6
3007.7
3238.7
3148.6
3011.2
3182.9
3349.7
3120
3257.5
3390
3077.8
Flux
Model
Cree XLamp XM-L {CW/NW/WW}
Current (A)
Model
T3 [220]
32
28
25
23
21
19
18
17
16
15
14
14
13
12
11
11
10
9
9
9
8
8
8
7
Tsp (ºC)
86.2
85.2
84.2
83.2
82.3
81.3
80.3
79.4
78.5
77.6
76.7
75.8
74.9
74.1
72.5
70.9
69.4
67.9
66.5
65.2
63.9
62.6
61.4
60.2
55
(none)
Flux
Price
Tj (ºC)
$
2
-
SYS W
35.17
35.42
35.82
36.87
37.27
37.03
38.24
39.13
39.69
39.91
39.8
42.37
41.75
40.77
41.51
45.7
45.39
44.34
47.86
51.41
48.86
52.03
55.21
51.1
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This document is provided for informational purposes only and is not a warranty or a specification. For product specifications, please see the data
Copyright © 2009-2011 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree, the Cree logo a
Figure
1: PCT view of the number of LEDs used and driving current
The PCT shows that, at 1.7 A, 8 XM-L LEDs provide sufficient light output to meet the design goals.
Thermal Requirements
For the 6-inch downlight in this reference design, we decided to use a commercially available housing, shown in Figure 2. We also decided
to use a commercially available heat sink, shown in Figure 3, attached to the back of the housing to dissipate the thermal load.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
5
XLamp ® XM-L LED 6-inch downlight Reference Design
Figure 2: Housing
Figure 4
Figure 3: Heat sink
We performed thermal simulations to verify this thermal design is sufficient. Figure 4 shows the thermal simulation results for the design.
The simulated solder point temperature (TSP) was determined to be 51 °C.
Figure 4: Thermal simulation of XM-L downlight
Driver
The driver for this 6-inch downlight can be mounted separate from the downlight and there is no driver size limit. This reference design
does not require a custom driver and we decided to use a constant-current off-the-shelf driver.
Figure 5: Driver
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
6
XLamp ® XM-L LED 6-inch downlight Reference Design
Secondary Optics
A diffuser is commonly used in downlight designs to minimize glare and hot spots and to distribute light evenly. This downlight design
uses a diffuser and a reflector to maximize light output. These two optical elements are contained in the housing.
Figure 7: Reflector
Figure 6: Diffuser lens
The reflector efficiency is ~99% and the diffuser efficiency is ~89%, giving a total optical efficiency of ~90%.
4. Calculate the number of LEDs
Using Cree’s PCT, we determined that 8 XLamp XM-L LEDs produce sufficient light to meet the 3000-lm design goal.
5. Consider all design possibilities
There are many ways to design an LED-based downlight. This reference design aims to show that a small number of XM-L LEDs enable a
downlight offering superior performance.
The XM-L LED offers a wide range of color temperatures. As highlighted in Table 6, we selected a warm white LED for this downlight
design. By selecting an LED from a low-level flux bin, we ensured that this design meets its goals using an LED that is readily available.
Table 6: XM-L order codes
Base Order Codes
Min. Luminous Flux @ 700 mA (lm)
CCT Range
Color
Min.
Max.
Cool White
5,000 K
8,300 K
Neutral White
3,700 K
5,000 K
80-CRI White
2,600 K
4,300 K
Warm White
2,600 K
3,700 K
Order Code
Group
Flux (lm)
T5
260
XMLAWT-00-0000-0000T5051
T6
280
XMLAWT-00-0000-0000T6051
T4
240
XMLAWT-00-0000-000LT40E4
T5
260
XMLAWT-00-0000-000LT50F4
T2
200
XMLAWT-00-0000-000HT20E7
T3
220
XMLAWT-00-0000-000HT30F7
T2
200
XMLAWT-00-0000-000LT20E7
T3
220
XMLAWT-00-0000-000LT30F7
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
7
XLamp ® XM-L LED 6-inch downlight Reference Design
6. Complete the final steps
Using the methodology described above, we determined a suitable combination of LEDs, components and drive conditions. This section
describes how Cree assembled the downlight and shows the results of the design.
Prototyping Details
1. We verified the component dimensions to ensure a correct fit.
2. Following the recommendations in Cree’s Soldering and Handling Application Note for the
XM-L LED with an appropriate solder paste and reflow profile, we reflow soldered the LEDs to
the metal core printed circuit board (MCPCB).
3. We soldered the input wires to the MCPCB.
4. We tested the connection by applying power to the LEDs and verified the LEDs lit up.
5. We applied a thin layer of thermal conductive compound to the back of MCPCB and attached
it to the heat sink.
6. We attached a round white reflector (with cutout openings matching the LEDs) to the MCPCB,
securing it with screws.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
8
XLamp ® XM-L LED 6-inch downlight Reference Design
7. We attached the housing to the heat sink with screws.
8. We attached the reflector to the bottom of the housing with screws. We attached the
reflector to the sides of the housing with double-sided tape.
9. We fit the diffuser lens into the housing and secured it with the diffuser cover trim.
10. We connected the LED DC input wires to the driver DC output wires with
connectors.
11. We performed final testing.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
9
XLamp ® XM-L LED 6-inch downlight Reference Design
Results
Thermal Results
Cree verified the board temperature with a thermocouple and an infrared (IR) thermal imaging camera
to confirm that the thermal dissipation performance of the heat sink aligns with our simulations. As
shown in Figure 8, the measured solder point temperature was 53 °C, which is in close agreement with
the simulation and shows that the heat sink is sufficient for this design.
Based on the measured solder point temperature of 53 °C, the junction temperature (TJ) can be
calculated as follows:
TJ= TSP + (LED power * LED thermal resistance)
TJ = 53 °C + (5.3 W * 2.5 °C/W)
TJ = 66 °C
Figure 8: Thermal results
for XM-L downlight
Estimated LED Lifetime
We used Cree’s TM-21 Calculator Tool to project the lifetime of the XM-L LED used in this downlight. Figure 9 shows the calculated
and reported lifetimes, determined using the TM-21 projection algorithm, for the XM-L LED at a 2-A input current at three solder point
temperatures. The duration of Cree’s XM-L LM-80 data set is 6000 hours at a 2-A drive current. Because the TM-21 methodology limits
the projection to six times the duration of the LM-80 data set, our TM-21 calculation shows a lifetime L70(6k) projection of greater than
36,300 hours. We are confident that most drivers can meet this temperature/lifetime requirement as well.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
10
XLamp ® XM-L LED 6-inch downlight Reference Design
TM-21 Lifetime Report
LED
I
Data Set
Tsp
Sample Size
Test Duration
α
β
Calculated Lifetime
Reported Lifetime
1
45°C
25
6,048 hrs
1.459E-07
9.847E-01
L70(6k) = 2,340,000 hours
L70(6k) > 36,300 hours
XLamp XM-L White
2000 mA
2
55°C
25
6,048 hrs
9.543E-07
9.887E-01
L70(6k) = 362,000 hours
L70(6k) > 36,300 hours
3
85°C
25
6,048 hrs
2.155E-06
9.834E-01
L70(6k) = 158,000 hours
L70(6k) > 36,300 hours
Reported L70
Calculated Lifetim
Reported Lifetime
110
105
100
95
% Luminous Flux
90
85
45°C (LM-80)
80
55°C (LM-80)
85°C (LM-80)
75
45°C (TM-21)
70
55°C (TM-21)
65
85°C (TM-21)
60
55
50
1,000
10,000
100,000
1,000,000
10,000,000
Time (hours)
Figure 9: XM-L TM-21 data
This document
is provided for
informational
only
is not
a warranty
or a specification.
For the
product
specifications,
Figure 10 shows
the calculated
and
reported purposes
lifetimes
forand
the
XM-L
LED, interpolated
from
data
shown in please
Figuresee9,the
at a measured
data sheets available at www.cree.com.
a reported
greater than
36,300 hours,
we expect
the lamp
to easily
meet
theCree,
design’s
lifetime
requirement.
53 °C TSP. With
Copyright
© 2011 L70(6k)
Cree, Inc. lifetime
All rights reserved.
The information
in this document
is subject
to change
without
notice.
the Cree
logo and
XLamp are registered trademarks of Cree, Inc.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
11
XLamp ® XM-L LED 6-inch downlight Reference Design
TM-21 Lifetime Report
XLamp XM-L White
2000 mA
Tsi (Interpolated)
LED
I
Ts1
Tsp
Tsp
Ea/kB
A
α
β
Calculated L70
Reported L70
Calculated Lifetime
Reported Lifetime
45°C
53°C
55°C
318.15 K
326.15 K
19608.38
8.5246E+19
6.616E-07
9.867E-01
L70(6k) = 519,000 hours
L70(6k) > 36,300 hours
L70(6k) = 519,000 hours
L70(6k) > 36,300 hours
328.15 K
1.459E-07
9.847E-01
L70(6k) = 2,340,000 hours
L70(6k) > 36,300 hours
9.543E-07
9.887E-01
L70(6k) = 362,000 hours
L70(6k) > 36,300 hours
110
45°C (LM-80)
105
55°C (LM-80)
100
85°C (LM-80)
45°C (TM-21)
95
55°C (TM-21)
90
% Luminous Flux
Ts2
85°C (TM-21)
85
53°C (TM-21)
80
75
L70: 519,000hrs
70
65
60
55
50
1,000
10,000
100,000
1,000,000
10,000,000
Time (hours)
Figure 10: XM-L TM-21 data with TSP = 53 °C
documentResults
is provided for informational purposes only and is not a warranty or a specification. For product specifications, please see the
Optical andThis
Electrical
data sheets available at www.cree.com.
2
Copyright
© 2011inCree,
Inc.7All
reserved.
The information
this document
is subject
change without
notice. Cree, time.
the Cree
logo
As
theand
table shows,
We obtained
the results
Table
byrights
testing
the downlight
in ain2-meter
sphere
after ato30-minute
stabilization
XLamp are registered trademarks of Cree, Inc.
the downlight meets the target goals of 3000 lm using less than 50 W of power. The downlight also meets the ENERGY STAR efficacy,
power factor, CCT and CRI requirements.
2
Testing was performed at the Cree facilities in Santa Barbara, CA.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
12
XLamp ® XM-L LED 6-inch downlight Reference Design
Table 7: XM-L downlight steady-state results
Characteristic
Light output (30 min on-time)
Power
Luminaire effic acy
Unit
XM-L Downlight
lm
3106
W
47.2
lm/W
65.9
CCT
K
3093
CRI
100-point scale
82
%
99.2
Power factor
We also tested the intensity distribution of the downlight.3 Figure 11 shows an even intensity distribution for the downlight with an 86°
beam angle.
Figure 11: Angular luminous intensity distribution of XM-L downlight
Table 8 shows the illuminance of the XM-L downlight at various distances from the light source.
3
Testing was performed in a type A goniometer at the Cree facilities in Shenzhen, China. An IES file for the downlight is available.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
13
XLamp ® XM-L LED 6-inch downlight Reference Design
Table 8: XM-L downlight illuminance – 86° beam angle
Height
Illuminance
Diameter
1m
3.3 ft
125.4 fc
1349.8 lx
185.6 cm
6.1 ft
2m
6.6 ft
31.4 fc
337.5 lx
371.3 cm
12.2 ft
3m
9.8 ft
13.9 fc
150.0 lx
556.9 cm
18.3 ft
4m
13.1 ft
7.8 fc
84.4 lx
742.5 cm
24.4 ft
5m
16.4 ft
5.0 fc
54.0 lx
928.1 cm
30.5 ft
6m
19.7 ft
3.5 fc
37.5 lx
1113.7 cm
36.5 ft
7m
23.0 ft
2.6 fc
27.6 lx
1299.4 cm
42.6 ft
8m
26.2 ft
2.0 fc
21.1 lx
1485.0 cm
48.7 ft
9m
29.5 ft
1.6 fc
16.7 lx
1670.6 cm
54.8 ft
10 m
32.8 ft
1.3 fc
13.5 lx
1856.2 cm
60.9 ft
Conclusion
This reference design illustrates the excellent results obtainable from a 6-inch downlight based on the Cree XLamp XM-L LED. The high flux
output of the XM-L LED enabled these results with a small number of LEDs, keeping system costs low. The directionality of the XM-L LED
is a plus in a downlight, putting more light on the surface to be illuminated. The downlight components in this design are all commercially
available, showing that an extremely capable luminaire can be designed without the time and expense of developing custom parts. The
lighting-class performance of the Cree XLamp XM-L LED makes it an attractive design option for an LED-based 6-inch downlight.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
14
XLamp ® XM-L LED 6-inch downlight Reference Design
Bill of materials
Table 9: Bill of materials for XM-L downlight
Component
Order Code/Model Number
Company
Web Link
Diffuser
C3-85
Bright View Technologies
www.brightviewtechnologies.com
Driver
EUC-060S170ST
Inventronics
www.inventronics-co.com
Heat sink
437
Foshan Xin Yi Kangke Metal Product
Co. Ltd.
www.fsxykk.com/EN/Default.asp
Housing
XN-8012
Xuning Hardware Plastic Products Co.,
Ltd.
www.hzsxn.diytrade.com
LED
Cree, Inc.
XM-L product page
Reflector
Flying Technology Co.
www.flyingtechnology.com
Reliance on any of the information provided in this Application Note is at the user’s sole risk. Cree and its affiliates make no warranties or representations about, nor assume any
liability with respect to, the information in this document or any LED-based lamp or luminaire made in accordance with this reference design, including without limitation that
the lamps or luminaires will not infringe the intellectual property rights of Cree or a third party. Luminaire manufacturers who base product designs in whole or part on any Cree
Application Note or Reference Design are solely responsible for the compliance of their products with all applicable laws and industry requirements.
Copyright © 2013-2016 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree® and XLamp® are registered trademarks and the Cree logo is a trademark
of Cree, Inc. ENERGY STAR® is a registered trademark of the U.S. Environmental Protection Agency. Other trademarks, product, and company names are the property of their respective owners and do not
imply specific product and/or vendor endorsement, sponsorship or association. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact
Cree Sales at [email protected]
15