Ssl Training December 2009 [Compatibility Mode]

Solid State LightingSeminarSeminar

December 2009

Agenda

•Cree Background

•SSL/LED Basics– Packages, Benefits, Light source comparisons

– Binning, Lifetime, Reliability, Standards, Safety

•Cree LED Components Portfolio

• Target Markets

Copyright © 2009 Cree, Inc. pg. 2

• Target Markets

• LED Design Considerations– Optics, Thermals, Electrical (with examples)

– Quality, Thinking ahead

• LED Roadmaps

•Cree Support

Presenters

Vince Feorenzo

Vice President

Americas Sales

Cree LED Components, RF


Steve Druckenmiller

Field Applications Engineer

Americas East

Cree LED Components, RF

Cree Background


Cree, Inc. Snapshot

LED Technology Leader

• Leading supplier of InGaN LED chips

• Created the first Lighting Class LEDs

• U.S. Patents: 827

• Foreign Patents: 1,800

Global Scale


Global Scale

• Locations: 12

• Employees: 3,200

• Headquarters: Durham NC, USA

Company Facts

• Revenue: $567.3 million (FY 2009)

• NASDAQ: CREE

Cree Global Footprint

• Headquarters:

– Durham, NC, USA

• Global Locations:

– Dulles, VA, USA

– Hong Kong

– Huizhou, China

– Munich, Germany

– Penang, Malaysia


– Penang, Malaysia

– Taipei, Taiwan

– Tokyo, Japan

– Santa Barbara, CA

– Seoul, Korea

– Shanghai, China

– Shenzhen, China

Chip

Manufacturing

Packaging

ManufacturingR&D Design Center

Cree - Leading the LED Lighting Revolution

1989Commercialized the first blue LED

2006First “Lighting-Class” LED components

2008Demonstrated record 161 lumens/Watt from LED component

2002Introduced1st XBright® LED power chip


1987Cree founded

1995Blue LEDs designed into VW

20071st commercially-viable LED downlight introduced (LR6)

2004First XLamp LEDs brought to market

2009Launched LED PAR38 Lamp with unrivaled color and efficacy

Cree Businesses

CreeCree


CreeCreeSiC/GaNSiC/GaNMaterialsMaterials

Cree LED Lighting Strategy

LED Lighting

• Lead the market & accelerate adoption

• Create demand/pull for LED lighting

LED Components

Market Opportunity

LED Lighting

LED Components

LED Components

• Drive Revenue

• Enable the market with “lighting-class” LEDs

LED Chips

• Technology to enable components

Materials

LED Chips

SSL/LED Basics


• LEDs consist of several layers of semiconductor material

• Light is generated in the PN junction when a current is applied

• LED light is monochromatic; the color depends on the materials

LED: Theory of Operation


color depends on the materials used and layer thickness

• There are two material systems (AlInGaP and InGaN) used to produce LEDs in all colors from blue to red

Typical High-Power LED Package

PhosphorESD protection

Wire bondReflector

Lens (glass, silicone)

Substrate/Lead Frame

Encapsulant

LED chip5mm


• The LED Package provides:– Protection for the LED chip from the outside environment

– Conductive path to carry generated heat away from the LED chip

– Lens & encapsulant systems to shape and direct the chip flux

• LED Chip: Determines raw brightness and efficacy

• Phosphor: Convert blue light to white. Determines white

color point and stability.

PhosphorESD protection LED chip5mm Type

• Thermal Resistance: Increase in junction

Typical LED Characteristics


Increase in junction temperature (TJ) above the solder point in °°°°C for every Watt of

electrical energy

• Viewing Angle: Commonly depicted

as full-width, half-maximum (FWHM)

Important Note: All LED data is for 20ms pulse, 25°°°°C

Beam Angle



• Temperature Coefficient of voltage:Describes the dependency of Forward Voltage (VF) on the junction temperature (TJ)

– The good news: This makes VF slightly lower at higher temperatures

• ESD ProtectionEvery LED has integral diode for Electrostatic Discharge (ESD) protection, in accordance with Human Body Model = 2kV

* Common to both warm and cool white LEDs



• DC Forward Current:(Max IF) is the maximum forward current the LED can safely and reliably withstand. Warm white LEDs are often rated lower on Max IF vs. cool white due to phosphor stability

* Common to both warm and cool white LEDs

• DC Pulse Current:Maximum DC current the LED can safely and reliably withstand for short pulse duration


• LED Junction Temperature (TJ)The maximum temperature the LED


• Forward Voltage:

The voltage for a given constant current, IF.

Typical and max shown

The maximum temperature the LED junction (light-generating part of the LED chip) can safely and reliably withstand before failure

• Correlated Color Temperature (CCT):Spectral bandwidth of white LEDs, defined as color temperature and x,ycoordinates



• Dominant Wavelength (DWL):Monochromatic wavelength of color LEDs

• Luminous Flux (LF):You will normally specify a specific LF bin from your supplier

– LF for Lighting-class LEDs are generally rated for 350mA IF

– LF is calculated for



– LF is calculated for higher drive currents

– Brighter bins generally cost more

– Warm white LEDs are generally about 25% lower LF than cool white for a given IF

Incandescent Compact FluorescentFluorescent

Traditional Lighting Technologies

• Very inexpensive

• Great color

• Very short lifetime

• Inexpensive

• Efficient

• Contains mercury

• Difficult to dim/control

• Energy efficient

• Contains mercury

• High price vs. incand.


Halogen High Intensity Discharge

• Inexpensive

• Efficient

• Long start time

• Poor color

• Extremely inefficient

• Difficult to dim/control

• Problems in cold temps

• High price vs. incand.

• Problems in cold temps

• Great color

• Focused light

• Very short lifetime

• Inefficient

Basic Advantages of LED Light

• LEDs are…very energy efficient �� >100LPW (near-term roadmap to >150LPW…)

• Are directional �� No wasted light, any pattern possible

•Have very long lifetime �� >50,000 hours to 70% Lumen Maintenance (L70)

• Are inherently rugged �� No filament to break


break

• Start instantly �� nanoseconds vs. > 10 min re-strike (HID)

• Are environmentally sound �� no Hg, Pb, heavy metals

• Are infinitely dimmable, controllable �� New lighting features, power savings

• Love cold temperatures �� No cold starting issues

Light TypeData Sheet

lm/WUsable*lm/W

Lifetime (hrs)

CRI

Incandescent 13-16 <15 3k 100

Halogen 20 12-20 6k 100

T12 fluorescent 60 40-50 20k 62-85

Metal halide 65-70 35-40 10k-20k 60-90

High-Power LED (Warm White) 80 55-65 50k+ 80-85

Light Source Comparison


T5 fluorescent 90 75-85 30k 85

T8 fluorescent 90+ 80-90 30-40k 78-85

High-pressure sodium 95-110 55-65 24k 22

Low-pressure sodium 120-140 65-75 16k <5

High-Power LED (Cool White) 132 >100 50k+ 75

* Typical expected performance in real-life applications. Based on mean lumens, and including ballast/driver, thermal equilibrium and typical fixture Coefficient of Utilization losses.

But source comparisons can be misleading. More to come …

• Chromaticity or Color Binning– Some defined “Box” in the

white area on or near the Black Body Locus (White LEDs)

– Dominant Wavelength (Color LEDs)

Binning - Two Main Types


• Brightness or Flux Binning– Minimum luminous flux or

radiant Flux

– Bin sizes (flux range) varies by supplier

Luminous Flux Binning

• LEDs are tested & sorted into luminous flux bins

• Bins are grouped into guaranteed minimum flux levels at a given drive (test) current

Flux:


73.9 lm

Driver350 mA

Flux:

1931 CIE Chromaticity Diagram

The 1931 CIE chromaticity scale gives everyone a common framework to reference very specific shades of color

White LED lamps are binned and sold based on the shade of white color represented on a


color represented on a chromaticity scale in terms of x, y coordinates and color temperature

How It Works• Monochromatic (direct) colors are on the

outside edge of the diagram

• All combinations of colors are on the inside, with white colors in the middle

Warm

Cool

Correlated Color Temperature (CCT)

• Not all “white” light lies directly on the BBL

• CCT refers to the Plankian black-body radiator color temperature (CT) that is closest to the color of the white light source (in Kelvin)


Examples of CCTsRelationship between CCT & CT

Blue (or UV) + Phosphor = White

• White LED light is generally made from a blue LED matched with a yellow phosphor

• Adding more red phosphor pushes the color temperature closer to the “warm” white CCT points…less, more to the blue

White Light

YellowPhosphor


points…less, more to the blue (“cool” white)

• The human eye is extraordinarily sensitive, so small process variations in chip wavelength; phosphor thickness, concentration, composition; and/or deposition conditions make a big difference

Blue LED

• David MacAdam – a scientist at Kodak - performed the research in the late 1940’s with the goal of determining a series of boundaries around several color targets (x, y coordinates) illustrating how much one can “ stray” from the target before perceiving a difference from that target color

• MacAdam found that these colorregions took the form of an ellipse on the CIE 1931 chromaticity chart

MacAdam Ellipses


on the CIE 1931 chromaticity chart

• A MacAdam Ellipse is defined as being the region on the CIE chromaticity chart in which the variations in color in that region are indistinguishable from the color of the point at the centerof the ellipse x

y

Note: The size and orientation of the ellipse varies significantly

MacAdam Ellipses (10X)


varies significantlywith it’s location in the CIE color space

1-step: One standard deviation (68.3%) of populati on perceives a color difference

2-step: Two standard deviation (97.5%) of populati on perceives a color difference

3-step: Three standard deviation (99.7%) of popula tion perceives a color difference

MacAdam Ellipse Steps


One Step

Two Step

Three Step

MacAdams In the “Real” World

0.38

0.39

0.40

0.41

0.42

0.43

0.44

0.45

CC

y

BBL+

2700 K

+

3000 K

+

3500 K

+

4000 K

4500 K

5000 K

5700 K

MacAdam Ellipse defines the chromaticity bin size


0.31

0.32

0.33

0.34

0.35

0.36

0.37

0.30 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.40 0.41 0.42 0.43 0.44 0.45 0.46 0.47 0.48 0.49 0.50

CCx

+

+

+

5700 K

+

6500 K

ANSI CFL Standard (7-steps)

ANSI C78.377A SSL Chromaticity Standard

2700K

3000K

3500K

4000K

4500K

5000K

5700K

0.37

0.38

0.39

0.40

0.41

0.42

0.43

0.44

0.45

0.46

Cree High-Power LED Chromaticity Binning

CCy: 0.35CCx: 0.32


6500K

8000K

0.28

0.29

0.30

0.31

0.32

0.33

0.34

0.35

0.36

0.37

0.2

8

0.2

9

0.3

0

0.3

1

0.3

2

0.3

3

0.3

4

0.3

5

0.3

6

0.3

7

0.3

8

0.3

9

0.4

0

0.4

1

0.4

2

0.4

3

0.4

4

0.4

5

0.4

6

0.4

7

0.4

8

0.4

9

CCy

CCx

ANSIC78.377A

Driver350 mA

Bin quadrangles (corners) are defined by four x,y pairs.

Cree High-Power LED Chromaticity Binning


Cree Kits (Order) codes vs. Bins

Kit code, aka Order code: used to describe a group of chromaticity and flux bins that are acceptable to fulfill an order.


Color Rendering Index System

3

2500

10

14

• Based on color comparison of 14 sample tiles with unsaturated colors

• Incandescent bulbs have CRI 100 (<5000K CT)


1

4

5

6 7

8

3000

4000

6000

2500

2

D65 9

11

12

13

14

• Sunlight is CRI 100 (> 5000K CT)

• LEDs (esp. RGB) have fully saturated colors and actually pay a mathematical penalty in the CRI system

CRI & CQS of Selected Light Sources

1 2 3 4

5 6 7 8

Source CRI

Low Pressure Sodium <5

High Pressure Sodium 20

RGB LED (typical) 31

Mercury Vapor 43

Cool White Fluorescent 63

Metal halide 64


9 10 11 12

13 14

Cool White LED 70

Daylight Fluorescent 76

Warm White LED (YAG) 81

Tri-phosphor Fluorescent 82

F32T8 Tri-phosphor 85

BSY + R LED 93

Halogen MR16 99

Incandescent 100

Color Rendering/Color Quality In Real Life


CRI = 62 CRI = 93

LED Reliability, Lumen Maintenance


LED Reliability Testing

• LEDs are semiconductor components that

happen to emit light

• Most LED manufacturers conduct the traditional standardized semiconductor component reliability testing on their LEDs (http://www.cree.com/products/pdf/XLamp_Reliability.pdf)

• Test methods vary among suppliers. Get the data!


Power LED White Point Stability Over Time

Warm White XR-E Chromaticity Shiftingduring 85C High Temp Operating Life Test

If = 700mA

0.006

0.008

0.010

• All power LED suppliers use different phosphor process, so color shift will vary. Get the test data!

• Low power LEDs will be different also (usually shift more).


-0.010

-0.008

-0.006

-0.004

-0.002

0.000

0.002

0.004

-0.010 -0.008 -0.006 -0.004 -0.002 0.000 0.002 0.004 0.006 0.008 0.010

u'

v'

1008 hours3145 hours4507 hours5087 hours4-step Macadam7-step Macadam

LED Lifetime vs Lumen Maintenance

50%

60%

70%

80%

90%

100%

110%

Lum

en O

utp

ut (%

)

100 W Incandescent

5mm LED

42W CFL

50 W Tungsten Halide400 W Metal Halide

25 W T8 Fluorescent

Lighting-class LED


40%

0 10 20 30 40 50 60 70 80 90 100

Operating Time (k hrs)

• Lighting-class LEDs become dimmer over time with no catastrophic failure

• End of life defined by the LED becoming too dim – needed to define Lumen Maintenance (L70)

• Not all LED types have a long L70 or lifetime

Courtesy LRC, Rensellaer Polytechnic Institute

Lumen Maintenance Definition

110%

Definition: change in light output of a light source over operational life, relative to initially measured light output

Lxx = time to xx% of original light output

• L70 = time to 70% of original light output

• L50 = time to 50% of original light output

How many hours until L70 is reached for LEDs? 50000 or longer?

Lumen Maintenance: Hypothetical HID Lamp Traditional light sources gradually


40%

50%

60%

70%

80%

90%

100%

0 5 10 15 20 25

Operating Time (k hrs)

Lum

en O

utp

ut (%

)

L70 = 10,000 hours

sources gradually dim then fail

catastrophically (“burn out”)

40,000 Hour / 4.5 Year XLamp Long-Term Data


Low temp (25ºC) testing is a good surrogate for the LED chip depreciation – 1-2% @ TJ = 65ºC

• At lower ambient air temperature, LEDs hardly depreciate at all.

Measured Data

• Widely adopted ASSIST method and exponential curve fitting• L70 is extrapolated from real measurement data• Is this accurate? Do all supplier’s LEDs degrade the same?

Predicting L70


LED Lumen Maintenance Standards

• The Illumination Engineering Society of North America published IES LM-80-2008 12 months ago to characterize the Lumen Maintenance aspect of LED semiconductor components


components

– For fixture companies to obtain Energy Star approval rating

– Helps define a standard test method between all LED suppliers

• Note: Lumen Maintenance ≠ LED Lifetime. The IESNA SSL

sub-committee (TM-21) is now working to develop an accurate algorithm for modeling long term LED behavior

LED Test Configuration Per IES LM-80-2008

Temperature of ambient around lamps is actively controlled by air flowing through chamber

• During test, the temperature of the solder pad of the lamps and the air around the lamps is the same

• Per LM-80,

− For 55ºC testing, the TSP of the lamps and air are both at 55ºC

− For 85ºC testing, the TSP of the lamps and air are both at 85ºC


Temperature of solder pad of lamps is independently actively controlled by fluid flowing through heat sink.

Lamps are mounted to MCPCB’s.

LED Lumen Maintenance Critical Parameters

1. TAIRAmbient Air Temperature

2. TJJunction Temperature

3. TSP / TC / TS


3. TSP / TC / TSSolder-Point Temperature / Case Temperature

4. IFForward Current /Drive Current

High Air Temperature Degrades Encapsulant

• Cree now understands that the silicone-based encapsulants used in the industry degrade when exposed to high temperatures

• Degradation comes from organic pendant groups (e.g. CH3, C6H5, -OH) that can off-gas or be trapped in the matrix

• The higher the air temperature, the more the encapsulant will degrade, the more light lost


• The out-diffusion of volatiles from silicone may be causing the refractive index of encapsulant to decr ease

• As the refractive index decreases the critical angl e increases allowing less light to be emitted from th e chip

Encapsulants Degrade Even Without Lighting the LED


Cree Power LED Lifetime Model - TM21 Consideration


• Degradation in first 5,000 hours is mostly due to degradation in the silicone encapsulant

• After 5,000 hours, this mechanism drops out and the slower chip degradation dominates

• We see no early life failures in our XLamp systems

L70 Lifetime Prediction – TAIR = 35ºC


L70 Lifetime Prediction – IF = 350 mA


LED Lumen Maintenance Summary

• Cree has accumulated millions of XLamp XR-E LED lamp device hours of long-term data under both LM-80-compliant conditions and other test configurations

• The effects of TAIR, TJ, TSP and IF on long-term lumen maintenance have been closely studied and are understood

• Cree has observed that the lumen maintenance characteristics of the XLamp XR-E white LED lamps are


characteristics of the XLamp XR-E white LED lamps are different in the first 5,000 hours (called Period A) than in the time period following 5,000 hours (called Period B)

• A “best fit” algorithm was developed to accurately model this behavior, based on critical parameters TAIR, TJ, TSP and IF

• This algorithm is likely to be different for every LED lamp system (e.g. XLamp XP, MC, Rebel, Dragon, NS6, etc…)

• L70 Lifetime Prediction ≠ LM-80

LED Eye Safety Standards and Regulations

IEC/EN 60825-1: Safety of laser products

• All Cree LED packaging still references this standard

1. The scope of IEC 60825-1 is limited to the end system, not the component. This makes sense because our customers can add optics that can either increase or decrease the eye safety risk of LEDs.


LEDs.

2. IEC removed LEDs from the scope of IEC 60825-1, so this standard no longer applies to LEDs. (Replaced by IEC 62471)

3. We have tested bare XLamp LEDs under IEC 60825-1 and all of them are rated as Class 2. We have the test report available.

IEC 62471: Photobiological safety of lamps and lamp systems

• How to evaluate photobiological safety of lamps and luminaires– Requires the lamp manufacturer (i.e., Cree) to evaluate the risk group of the

lamp itself

– ALSO requires the entire luminaire to be tested

• Provides no guidance on how to label products

LED Eye Safety Standards and Regulations


• Provides no guidance on how to label products

• Classifications are:– Exempt

– RG-1 (Low Risk)

– RG-2 (Moderate Risk)

– RG-3 (High Risk)

LED Eye Safety Labeling Requirements

United States

IESNA/ANSI RP-27.3-07: Recommended Practice for Photobiological Safety for Lamps - Risk Group Classification and Labeling

• Requires small changes to packaging & data sheet information

• Also requires absolute spectral power data to be available on request– Eye Safety application note coming soon to provide this “on request” data in one


– Eye Safety application note coming soon to provide this “on request” data in one place online & explain relevant standards

EU

• Currently most states may use IEC 62031:2008 LED Modules for General Lighting – Safety Specifications

• Our understanding is that EU is moving to adopt IEC 62471 in its place

• Labeling standard may be coming soon and may require another change to labels / data sheets separate from ANSI RP-27

SSL Standards Status

Standard Draft CommentComment Resolution

Projected Publication

IESNA RP-16Definitions

X X X Complete

ANSI BSR C78.377A, Chromaticity

X X X Complete

IESNA LM 79, Luminous Flux

X X X Complete

IESNA LM 80, Lumen Depreciation

X X X Complete

NEMA SSL-1,

Status of ANSI, IESNA, and CIE Solid State Lighting Standards (Partial List)


NEMA SSL-1, SSL Drivers

X

NEMA LSD-44 & 45, (SSL-2)SSL Interconnect

X X

NEMA SSL-3, LED Binning

X

TM-21,Lumen Maintenance Extrapolation Method

X

NEMA-ALA Joint White PaperDefinition of Functional & Decorative Lighting

X

IESNA LM-xx,LED Light Engine & Lamp Measurement

X

CIE S009, Photobiological Safety

X X

List of SSL Standards In Progress (4/2009)

• Additional primary standards identified or underway– CIE TC1-69 Color Quality Scale (new CRI type metric)– C82.SSL1 LED Drivers– UL 8750 Safety– TM-21 Lumen Maintenance Extrapolation Method – LM-XX1 Methods for the Measurements of High Power LEDs– LM-XX2 LED “Light Engine” Measurements (PIF for approval)– LM-XX2 Photometric Testing of Outdoor LED Luminaires (based on LM-10/31)– RP-16 Additional LED Definitions– C78.SSL2 LED Sub-assembly Interfaces– C78.SSL3 Binning Standards– C78.SSL4 Form Factors – ANSI SSL2 LSD-45 Sockets & Interconnects Consistency Standard – ANSI C82.4 Driver Performance Standard – CIE TC2-46 CIE/ISO LED Intensity Measurements


– CIE TC2-46 CIE/ISO LED Intensity Measurements– CIE TC2-50 Optical Properties of LED Arrays– CIE TC2-58 Luminance and Radiance of LEDs – IEEE P1789 – Recommended Practices of Modulating Current in High Brightness

LEDs for Mitigating Health Risks to Viewers– IEC SC 34A – Performance Standard for LED Lamps– IEC SC 34A 62031:2008 LED Modules – Safety– IEC SC 34C 61347-2-13:2006 – Lamp Controlgear – Part 2-13: DC or AC Controlgear for LED Modules– IEC SC 34A IEC 62560 Self-Ballasted LED Lamps– IEC SC 34A <tbd> LED Lamps > 50 V – Safety Specs

• Cree XLamps XPE Power LEDs are UL Recognized– Pass UL8750 proposed safety testing

Cree LED Components


High-Bright LED Product Families

P4


P2 Round

Screen Master P2 Oval PLCC/SMD

P2 Round – 5mm

• Single Color Signs:

– C503 series has been the most popular

• Available in Red, Green, Blue, Amber, & White

– Amber/Red have found success in transportation and roadway signs

• New min 15°°°° & 30°°°° amber will be coming out soon targeted

towards the transportation market


towards the transportation market

– Typical applications for White include:

• C503 = 15°°°° �� Torch/Flashlight

• C512 = 25°°°° �� Torch/Flashlight – Garden Light

• C513 = 55°°°° �� Advertisement Boxes

• C543 = 20°°°° �� Garden Light

• C534 = 140°°°° �� Garden Light

• C535 = 110°°°° �� Garden Light

P2 Oval – 4mm & 5mm

• Full Color Video Screens:

– C4SMF-RJS, C4SMF-GJS, C4SMF-BJS

– C4SMG-RJS, C4SMG-GJS,C4SMG-BJS

• The Right LED for the right application

– C5SM

• Available in R/G/B/Amber


• Available in R/G/B/Amber

• Different brightness family available

• 110°°°°x40°°°° viewing angle

– ScreenMaster family has a matched RGB far field pattern

– C566 series

• Red/Amber for monochrome displays


Product Family – P4

• CP41 series

– Round lens

• Normal Lambertian pattern

– Available in R/G/B/A/W

– Various Viewing Angles

• CP42 series

– Concave lens


– Concave lens

• Batwing radiation pattern

– Available in R/G/A

• CP43 series

– Oval lens


– Available in Red/Amber

Copyright © 2009, Cree, Inc.

pg. 62

pg. 62

Product Family – PLCC families (Full Color)

• CLP6C-FKB �� 6050 (6mm x 5.5mm) package

– R(560-1120mcd), G(1120-2240mcd) & B(280-560mcd)

• CLP6S-FKW �� 6050 (6mm x 5.5mm) package

– R(710-1800mcd), G(710-1800mcd) & B(280-710mcd)

• CLV1A-FKW �� 3228 (3.2mm x 2.8mm) package

– R(355-900mcd), G(560-1400mcd) & B(180-450mcd)


– R(355-900mcd), G(560-1400mcd) & B(180-450mcd)

• CLPPA �� 3228 (3.2mm x 2.8mm) package

– R(180-450mcd), G(280-710mcd) & B(71-180mcd)

• CLV6A-FKB (5.5mm x 5.5mm) package

– First SMT LED with IPx5 rating

– Water resistant

– No polycarbonate cover needed for outdoor color display

Product Family – PLCC families (Single Color)

• CLP6C �� 6050 (6mm x 5.5mm)

– Red(3550-7100mcd)

– Amber(3550-9000mcd)

• CLM6S �� 3533 (3.5mm x 3.3mm)

– Green(1120-2800mcd)

– Blue(355-900mcd)

• CLM6T �� 3533 (3.5mm x 3.3mm)

– Red (710-1800mcd)

• PLCC4:

– CLM2B �� with lens (60°°°° VA)

• Red (2240-5600mcd)

• Amber (3550-9000mcd)

– CLM2T �� with lens (60°°°° VA)

• Amber (1120-2800mcd)


• CLM4B �� 3227 (3.2mm x 2.7mm)

– -AKB: Amber(1120-2800mcd) (black face)

– -GKW: Green(1400-3550mcd)

– -BKW: Blue(355-900mcd)

– -PKW: Orange(1120-2800mcd)

– RKW: Red(1120-2800mcd)

– -AKW: Amber(1120-2800mcd)

• PLCC2:

– CLM3C �� 2720 (2.7mm x 2.0mm)

• Red (560-1400mcd)

• Amber (355-900mcd)

– CLM3S �� 2720 (2.7mm x 2.0mm)

• Blue(112-355mcd)

Product Family – PLCC families (Single Color)

• CLM4S-DKB �� 3228 (3.2mm x 2.8mm) package

– Red(140-355mcd) & Green(280-900mcd)

• CLM4S-DKW �� 3228 (3.2mm x 2.8mm) package

– Red(140-355mcd) & Green(280-900mcd)

• CLM4TS-RDK �� 3227 (3.2mm x 2.7mm) package

– Red(560-1400mcd)


– Red(560-1400mcd)

• CLM1B �� 3227 (3.2mm x 2.7mm) package

– Blue(280-710mcd) & Green(710-2240mcd)

– Red(450-1120mcd) & Amber(355-900mcd)

• CLM1S �� 3227 (3.2mm x 2.7mm) package

– Blue(112-355mcd) & Green(355-1120mcd)

• CLM1T �� 3227 (3.2mm x 2.7mm) package

– Red(280-560mcd)

Product Family – PLCC families (White)

• CLN6A ��5050 Package (5mm x 5mm)

– CW = 60.5-101.8 lm

– WW = 51-101.8 lm

• CLP6B �� 6050 (6mm x 5.5mm) package

– CW = 7,100-18,000mcd

– WW = 7,100-14,000mcd

• CLP6S �� 6050 (6mm x 5.5mm) package

– CW = 3,550-7,100mcd / WW = 2,800-7,100mcd

• CLM3C �� 2720 (2.7mm x 2.0mm) package

• CW = 1,400-3,550mcd

• WW = 1,120-2,800mcd

• CLM3A �� 2720 (2.7mm x 2.0mm) package

• Cool White = 1,120-2,240mcd


• CW = 355-1,120mcd


7,100mcd

• CLA1A �� no lens, 3228 (3.2mm x 2.8mm) package

– CW = 1,800-4,500mcd

– WW = 1,400-3,550mcd

• CLA2A ��2 die, 3228 (3.2mm x 2.8mm) package

– CW = 2,240-5,600mcd

• CLM1C �� 3227 (3.2mm x 2.7mm) package

• CW = 710-1,800mcd


• WW = 355-1,120mcd

HB – Smart Part Numbering System

Single Color: CAAAB-DEG-ZHHKKMNTRGB: CAAAB-DEG-ZHhJjKkLlMmT


Which HB LED to use (and where)?

• Why use Round LEDs?– Mostly used in Single

color signs

– Variety of viewing angles

(15°°°°, 23°°°°, 30°°°°, 50°°°°, >70°°°°)– Available in R/G/B/A/W

– 3mm & 5mm available

• Why Use Oval LEDs?– Full Color Video Displays

– Wider viewing angle

• 110°°°°x45°°°°, 70°°°°x35°°°°– Screen master series has a

matched RGB field pattern

– 4mm & 5mm available


• SMD / PLCC package– SMD 3-in-1 for Full Color Video

– White PLCC for linear lighting & light bulb applications

– New IPx5 rated (outdoor)

– Black Face & White face/body

– PLCC2/4/6

• P4 LEDs –– Used more for Channel Letters

and Automotive and Advertising Boxes

– Different lenses for various radiation patterns

High-Power XLamp LED Product Families


What are Lighting-Class LEDs?

Quality

Only

LEDs have the light output, efficacy, quality of light

and reliability to replace traditional lighting sources

Lighting-Class

Flux & Efficacy

• 120+ LPW

• Energy Savings

• Small source size(direct light where needed)

• ANSI chromaticity bins & sub-bins

• Consistent reels of


Reliability

Quality of Light

traditional lighting sources• Consistent reels of

LEDs

• High standard CRI

• Color point stability

• Energy Star approved lumen maintenance

• Lifetime prediction

• Maintenance Avoidance

Cree XLamp LED Product Portfolio – White

XLampSingle Die Multiple Die

XR-C XR-E XP-C XP-E XP-G MC-E MX-6



Footprint (mm)

7.0 x 9.0 3.45 x 3.45 7.0 x 9.0 6.5 x 5.0

Max Current

500 mAUp to

1000 mA500 mA 700 mA 1000 mA

700 mA(per LED)

350 mA

Viewing Angle

90° 90° 110° 115° 125° 110° 120°

LM-80 accepted LM-80 accepted LM-80 accepted

XLamp XR-E & XR-C White


• Long history of LED innovation and reliability:

2006 First lighting-class cool white LED

2007 First lighting-class warm white LED

First LED offered in ANSI C78.377A chromaticity binsFirst 100 lumen cool white LED to ship in volume

2009 Approved as DOE Energy Star SSL compliant for lumen maintenance

• Tens of millions of LEDs shipping per quarter

• Lighting up LED industry’s most high-profile installations

XLamp XP-E & XP-C White


• Small footprint device

• Symmetric design offers matching mechanical and optical center– Improves optical efficiency

– More efficient secondary optics

– Easier manufacturing

XLamp XP-E White Characteristics & Features

Cool White Neutral White Warm White

CCT (K) 10,000K – 5,000K 5,000K – 3,700K 3,700K – 2,600K

Viewing Angle 115º 115º 115º

Thermal Resistance (ºC/W) 9 9 9

Max Current (mA) 700 700 700

Typical Vf @ 350 mA (V) 3.2 3.2 3.2


Typical Vf @ 350 mA (V) 3.2 3.2 3.2

Features

• ANSI-compatible chromaticity bins

• Accepted by U.S. DOE for ENERGY STAR lumen maintenance

• Electrically neutral thermal path

• High maximum LED junction temperature: 150ºC

• Unlimited floor life at ≤30ºC / 85% RH

• Reflow solderable JEDEC J-STD-020C compatible

• RoHS and REACH-compliant

• UL-recognized component (E326295)

XLamp XP-C White Characteristics & Features


CCT (K) 10,000K – 5,000K 5,000K – 3,700K 3,700K – 2,600K



Max Current (mA) 500 500 500

Typical Vf @ 350 mA (V) 3.4 3.4 3.4


Typical Vf @ 350 mA (V) 3.4 3.4 3.4

Features

• ANSI-compatible chromaticity bins







XLamp XP-G White


• Raises the bar of LED performance– Up to 367 lumens (111 LPW) @ 1000 mA

– Reduce system cost with fewer LEDs & fewer optics

• Unbeatable efficacy at low current– Up to 132 LPW typical @ 350 mA

– Smaller / fewer batteries or solar cells

XLamp XP-G Characteristics

Cool White

CCT (K) 8,300K – 5,000K

Viewing Angle 125º

Thermal Resistance (ºC/W) 6

Max Current (mA) 1000

Typical Vf @ 350 mA (V) 3.0

Min. Flux Bin

8,300K –5,000K

51, 53, 50

R5 (H) 139

R4 (G) 130

R3 (F) 122

R2 (E) 114


Typical Vf @ 350 mA (V) 3.0

Features

• ANSI-compliant chromaticity bins




• REACH and RoHS-compliant


XLamp XP-C/XP-E/XP-G WhiteStandard Order Codes

Min. Flux Bin

10,000K –5,000K

5,000K –4,200K

4,200K –3,500K

3,500K –3,200K

3,200K –2,900K

2,900K –2,700K

01, 02, 03, … E3, F4, E4 F5, E5 F6, E6 F7, E7 F8

S2 (J)* 148

R5 (H) 139

R4 (G) 130

R3 (F) 122

R2 (E) 114

XP-E

XP-E & XP-C

XP-G

XP-E & XP-G


R2 (E) 114

Q5 (D) 107 107

Q4 (C) 100 100 100

Q3 (B) 93.9 93.9 93.9 93.9

Q2 (A) 87.4 87.4 87.4 87.4 87.4

P4 (9) 80.6 80.6 80.6 80.6 80.6 80.6

P3 (8) 73.9 73.9 73.9 73.9 73.9 73.9

P2 (7) 67.2 67.2 67.2 67.2

N4 (6) 62.0 62.0 62.0

N3 (5) 56.8 56.8

XP-E & XP-C

XP-C

Minimum luminous flux @ 350 mA (lm)* Limited quantities

XLamp XPC/XPE/XPG Part Numbering System

LEDs are purchased with Order Code; Bin Code appear s on reel


XLamp MX-6 White

The new lighting-class standard for indoor LED lighting


The new lighting-class standard for indoor LED lighting

• Best color consistency– ANSI warm white sub-bins (75% smaller than ANSI quarter-bins)

• Best efficacy– High lumen output with low forward voltage (3.3V typ)

• Drop-in upgrade for Nichia NS6/NS3– Better thermal and electrical performance, same footprint

XLamp MX-6 White Characteristics & Features

Cool White Warm White

CCT (K) 8.300K – 4,300K 4,300K – 2,600K

Viewing Angle 120º 120º

Thermal Resistance (ºC/W) 5 5

Max Current (mA) 350 350

Typical Vf @ 300 mA (V) 3.3 3.3


Typical Vf @ 300 mA (V) 3.3 3.3

Typical Vf @ 350 mA (V) 3.4 3.4

Features

• ANSI-compliant chromaticity bins




• REACH and RoHS-compliant

XLamp MX-6 WhiteStandard Order Codes

Min. Flux Bin

8,300K –5,000K

5,000K –4,000K

4,000K 4,000K –3,200K

3,200K –2,900K

2,900K –2,700K

51, 53,50 DZ,F4, E4, F5 E5 F6, E6 F7, E7 F8

Q5 (D) 107 [122]

Q4 (C) 100 [114] 100 [114]

Q3 (B) 93.9 [107] 93.9 [107] 93.9 [107]


Q3 (B) 93.9 [107] 93.9 [107] 93.9 [107]

Q2 (A) 87.4 [100] 87.4 [100] 87.4 [100] 87.4 [100]

P4 (9) 80.6 [92] 80.6 [92] 80.6 [92] 80.6 [92]

P3 (8) 73.9 [84] 73.9 [84]

P2 (7) 67.2 [77]

Minimum luminous flux @ 300 mA [Calculated min @ 350 mA] (lm)

XLamp MX6 Part Numbering System



XLamp MC-E White


• Cree’s 4 power chip LED package

• Offers 4x the flux of XLamp XR-E in the same footprint and with the same lighting class performance

• Can reduce total LED system cost by reducing the number of LEDs & optics

XLamp MC-E White Characteristics & Features


CCT (K) 10,000K – 5,000K 5,000K – 3,700K 3,700K – 2,600K



Max Current (mA)700

(per die)

700 (per die)

700(per die)

3.2 3.2 3.2


Typical Vf @ 350 mA (V)3.2

(per die)

3.2(per die)

3.2(per die)

Features

• Accepted by U.S. DOE for ENERGY STAR lumen maintenance





Min. Flux Bin

10,000K –5,000K

5,000K –4,200K

4,200K –3,500K

3,500K –3,200K

3,200K –2,900K

2,900K –2,700K

01, 02, 03, … E3, F4, E4 F5, E5 F6, E6 F7, E7 F8

M 430

K 370 370 370

J 320 320 320 320

H 280 280 280

XLamp MC-E WhiteStandard Order Codes


H 280 280 280

G 240 240

Minimum luminous flux @ 350 mA (lm)Flux and chromaticity are measured with each LED die connected to independent drive circuits at 350 mA. The flux and chromaticity are measured with all LEDs lit simultaneously.

XLamp MCE Part Numbering System



Cree XLamp LED Product Portfolio – Color


XR-C XR-E XP-E MC-E


XR-C XR-E XP-E MC-E

Footprint (mm)

7.0 x 9.0 3.45 x 3.45 7.0 x 9.0

Max Current

Up to 700 mA

Up to 1000 mA

Up to 1000 mA

700 mA(per LED)

Colors

Royal Blue

Blue

Green

Amber

Red-Orange

Red

Royal Blue

Blue

Green

Royal Blue

Blue

Green

Amber

Red-Orange

Red

A1 (RGB CW)

B1 (RGB NW)

XLamp XP-E Color

• Breakthrough color flux output– 20% brighter than XLamp XR-C Amber, Red, Red-Orange


– 20% brighter than XLamp XR-C Amber, Red, Red-Orange

– 6% brighter than XLamp XR-E Royal Blue, Blue, Green

• Small footprint device

• Compatible with Lumileds Rebel optics

• Symmetric design offers matching mechanical and optical center– Improves optical efficiency

– More efficient secondary optics

– Easier manufacturing

XLamp XP-E Color Characteristics & Features

Royal Blue

Blue Green AmberRed-

OrangeRed

DWL (nm) 450-465 465-485 520-535 585-595 610-620 620-630

Viewing Angle 130º 130º 130º 130º 130º 130º

Thermal Resistance (ºC/W) 9 9 9 15 15 15

Max Current (mA) 1000 1000 1000 500 700 700


Typical Vf @ 350 mA (V) 3.2 3.2 3.4 2.2 2.2 2.2

Features







XLamp XP-E ColorStandard Order Codes

Min.FluxBin

Blue Green Amber Red-Orange

Red

465-485 520-535 585-595 610-620 620-630

Q4 100

Q3 93.9

Q2 87.4

P4 80.6

P3 73.9

Min. Flux Bin

Royal Blue

450-465

15 425


P3 73.9

P2 67.2 67.2

N4 62.0

N3 56.8

N2 51.7 51.7 51.7

M3 45.7 45.7 45.7

M2 39.8 39.8 39.8

K3 35.2 35.2

K2 30.6 30.6 30.6

J0 23.5

15 425

14 350

Minimum luminous flux @ 350 mA (lm)

Minimum radiant flux @ 350 mA (mW)

XLamp MC-E Color (RGBW)


• Unique RGBW LED combination

• High lumen output from a single device– Up to 500 lm total when driven @ 700mA per die

• Reduces space between color LED die to almost nothing – Small, multi-color optical source for efficient color mixing

– Reduces number of optics

• Lower system component count can reduce total system complexity & cost

XLamp MC-E Color Characteristics & Features

Configuration A1 B1

Color Blue Green Red White Blue Green Red White

DWL (nm) / CCT 450-465 520-535 620-630 6500K 450-465 520-535 620-630 4000K

Min. Luminous Flux@ 350 mA (lm)

8.2 67.2 30.6 95 8.2 67.2 30.6 80

Typical Vf @ 350 mA (V) 3.2 3.4 2.2 3.2 3.2 3.4 2.2 3.2

Max Current (mA) 700 700 700 700 700 700 700 700


Viewing Angle 115º 115º

Thermal Resistance (ºC/W) 3 3

Features




• RoHS-compliant

MPW-EZW (Easy White)

• 8-8-8 chip configuration

• 2700K, 3000K, 3500K

• No CCT binning req’d;4-step MacAdam ellipse

• LF binned at 250mA

– ~1250 lm @ 2700K

– ~1350 lm @ 3000K


– ~1350 lm @ 3000K

– ~1450 lm @ 3500K

• Up to 20W power dissipation

– 2°°°°C/W RTH

• Typical CRI: 80

• >50,000 hrs L70 per IES LM-80-2008

• 1Q10 general release

MPL-EZW The Big Benefit


Let Cree do the mixing for you...EasyWhite

• Consistent color

• No complicated mixing recipes

• Reduced inventory

• Ease of manufacturing

• No Special Bin Order Codes (reduce cost)

Cree LED Target Markets


The Market OutlookRevenue (Billions)

HB LED Market*

Conventional Lighting

General Illumination Market**

Revenue (Billions)


Revenue (Billions)

LED Lighting

Lighting

Revenue (Billions)

LED market growth is being driven by two major trends:

Notebook & TV backlighting (short cycle)

General Lighting (long cycle)

** Source: Philips Lighting

LED Components – Market Segments

Indoor Lighting Portable Lighting


Outdoor Lighting LED Light Bulbs

Video Screens & Signs

Transportation & EVL

Architectural

Current LED Lighting Applications


Video Screens – High Bright LEDs

Screen Master P2 Oval

C4SMG C4SMF C5SMF

Matched Radiation Red / Green / Blue

4mm – 100°x45° 4mm – 100°x45° 5mm – 100°x40°

12 – 16 mm pitch 16+ mm pitch 20+ mm pitch


SMD – Black Face

CLV1A-FKB CLV6A-FKB

Full Color (Red / Green / Blue) – Vertical Alignment

PLCC4 – 120° PLCC6 – 120°

4 – 10 mm pitch 10 – 16 mm pitch

IPx5 rated (water resistant)

Signs, Signals & Channel Letters – HB LEDs

P2 5mm Round P2 5mm Oval

C503B-xAx C503B-xBx C503B-xCx C566C-xFx

A / R / G / B A / R A / R / G / B A / R / G / B

15° 23° 30° 70°x35°


P4 Round

CP41B-xxS CP41B-xxS CP42B-xKS

A / R G / B / W A / R / G

40° / 70° / 100° 60° / 70° / 90° 120°

Outdoor (Area) Lighting is a Diverse Space

“Cobra Head” Industrial “Wall Pack”

Parking/Canopy/Low Bay

Ornamental/Pole Top

Parking/“Shoe Box”


• 60 million unit installed base in North America alone

LPS HPSMetal

HalideLED

“Boiler Plate” Efficacy (LPW) 130 95 70 105

Delivered Efficacy* (LPW) 70 51 38 75

CRI <5 22 60-80 70-80

Typical CCT 1800 2000 3000-4000 Any

Lifetime (hours) 16k 24-30k 10-20k >50k

* Incl. 60% CU + 10% ballast factor for HID; 85% CU, 88% driver efficiency, -10% thermal equilibrium for LED

• Most use one of three HID lamp types:

Outdoor Lighting – XLamp Power LEDs

Outdoor Lighting

XLamp XR-E XLamp XP-G XLamp MC-E

Cool White (75 CRI) – 5000K-10,000K

Up to 107 lm min Up to 130 lm min Up to 430 lm min


93 lm/W 124 lm/W 96 lm/W

Making the Business Case Work


Initial applications will be driven by maintenance avoidance & energy savings– Street & Parking lot lighting– Parking garages– Atrium– Tunnels– Hazardous work areas

Light Source Comparison

150W MH Street Light Example

$600

$800

$1,000

$1,200

Cumulative Lifecycle Costs 150WMetal HalideCumulative Lifecycle LED Cost(350mA)Cumulative Lifecycle LED Cost(700mA)

2-3 Year Payback For End Customer


$-

$200

$400

2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

LEDs make a compelling maintenance and energy savings value proposition now

Attractive Financial Proposition For Fixture Co.

Tota

l Fix

ture

CoO

*

$800

10-year Cost of Ownership*150W MH Street Light

$1,200

$1,000

Labor

Bulb

Labor

Bulb

Labor

Maintenance

Events


Tota

l Fix

ture

CoO

*

$400

$0

$800

Conventional HID Fixture

$600

LED Fixture

$200MetalHalideFixture

Initial Fixture

Sale

LEDFixture

EnergyEnergy

Bulb

Labor

U.S. DOE Gateway Project

Rayley’s Supermarket, Chino, CA


Before: 346W Metal Halide After: 149 W Bi-level LED System52W when dimmed

• 70% Energy Savings

• 3.3/4.7 year simple payback (new construction/retrofit)

• Perceived improvement in safeftyhttp://www1.eere.energy.gov/buildings/ssl/gatewaydemos_results.html

Tianjin Polytechnic University

• 2,000 roadway luminaires installed


• Primary motivation: Energy Savings

NC State University Parking Deck

Before: HID


NC State University Parking Deck

After: 27% Energy SavingsVastly Improved LightingLess Fixtures (wider spacing)


Indoor Lighting

Indoor Lighting

XLamp XP-E XLamp MC-E XLamp MX-6 MPL-EZW

Warm White (80 CRI) – 2600K-3700K

Up to 93.9 lm min Up to 320 lm min Up to 87.4 lm minUp to 1365 lm @

250mA

Neutral White (75 CRI) – 3700K-5000K

Up to 100 lm min Up to 370 lm min Up to 93.9 lm min


Indoor Applications

• Different requirements than outdoor

– Warm White Color Temperature (2700-3000K) required

– High CRI (>80)


– Lamp maintenance nota driving factor

– High style content

– Focus on energy, green

– Different market channels, cost expectations (consumer product)

Yes, these are LED!

Indoor: Restaurants


• 80% Energy Savings

• Excellent Color Rendering

Residential Installations


High-End Retail Hotel Installation


LED Light Bulb & Landscape Lighting

Linear Tube

CLA1A-xKW CLP6B-xKW XLamp MX-6

Cool / Warm White

3.2 x 2.8 mm 6.0 x 5.0 mm 6.5 x 5.0 mm

35 mA max 150 mA max 350 mA max

Light Bulb

XLamp MX-6 XLamp XP-E XLamp MC-E MPL-EZW


Cool / Warm White Cool / Neutral / Warm White Warm White

6.5 x 5.0 mm 3.45 x 3.45 mm 7.0 x 9.0 mm 13 x 12 mm

350 mA max 700 mA max 700 mA max (per die)

250mA per die

Landscape Lighting

C503D-WAN C535A-WJN CP41B-WxS

Cool White

P2 Round – 15° P2 Round – 110° P4 Round – 60° / 90°

30000 mcd typ 1400 mcd typ 7000 mlm typ

Standard LED Components �� LED bulbs


Happening Now

• Longer life

• Much better efficacy than incandescent; lower efficacy than CFL

• Generally pretty low CRI (~75-82, 3000K)

• Today, light output matches only the lowest wattage incumbents

System

Watts 20

08

20

09

20

10

20

11

20

12

Wattage

Equivalent*

1.0 84 92 101 112 123

2.0 161 177 195 214 235

3.0 231 254 279 307 338

4.0 294 324 356 392 431

5.0 351 386 425 467 514

6.0 401 441 485 533 587

7.0 444 488 537 590 649

8.0 480 528 580 638 702

35W

20W

6500K

MR16 Using Standard LED Components

System

Watts 20

08

20

09

20

10

20

11

20

12

Wattage

Equivalent*

1.0 63 69 76 84 92

2.0 121 133 146 161 177

3.0 173 191 210 231 254

4.0 221 243 267 294 323

5.0 263 289 318 350 385

6.0 300 331 364 400 440

7.0 333 366 403 443 487

8.0 360 396 435 479 527

20W

35W

3000K

L70

Lim

itatio

ns


8.0 480 528 580 638 702

9.0 509 560 616 677 745

10.0 531 585 643 707 77850W

* Lumen equivalence, CBCP target probably be more practical

8.0 360 396 435 479 527

9.0 382 420 462 508 559

10.0 399 438 482 531 584

35W

• 20W halogen equivalent* @ 3000K possible now

• 35W equivalent* @ 3000K looks possible later

• 50W equivalent* @ 3000K looks challenging

• Thermal limitations inherit to the form factor

L70

Lim

itatio

ns

Portable

High-End

XLamp XR-E XLamp XP-G XLamp MC-E

Cool White

7.0 x 9.0 mm 3.45 x 3.45 mm 7.0 x 9.0 mm

Up to 107 lm min Up to 130 lm min Up to 430 lm min


Mainstream

XLamp XP-E XLamp XP-C CLN6A-WKW C503D-WAN

Cool White

3.45 x 3.45 mm 3.45 x 3.45 mm 5.0 x 5.0 mm 5mm 15°

Up to 114 lm min Up to 93.9 lm min Up to 85.6 lm min 30,000 mcd typ

Architectural, Transportation – XLamp LEDs

Architectural, Transportation Color Lighting

XLamp XP-E XLamp MC-E

Red, Green, Blue, Amber RGBW


Water Cube at Beijing Olympics 2008


Bird’s Nest at Beijing Olympics 2008


LED Design Considerations


LED Design Considerations

Electrical, Thermal & Optical: All Affect Light Output

Electrical• Integrated systems approach;

fixture designed around LEDs

• LED light is different than existing light technologies

• Not intuitive at first

Thermal


Deliveredlumens

Optical

DeliveredLPW

• These charts are on all LED data sheets; familiarization with them is essential to good results

LED Luminaire Design Will Be Different…

LEDConventional Lighting

Ref

lect

or


• LED Light is inherently directional

• LED thermal path accomplished by conduction – No IR, no UV in the light beam

• Retrofit of conventional fixtures may not leverage all the benefits of LEDs

LightHeat

Process for Designing LEDs into Luminaires

1. Define lighting requirements of application

2. Define design goals for LED luminaire

3. Estimate efficiencies of optical, thermal and electrical subsystems


4. Calculate the number of LEDs needed

5. Build a prototype and test against design goals

1) Define Lighting Requirements

? What kind of light is required in this application?

Importance Characteristic Unit

Critical

Luminous flux lumens (lm)

Illuminance distribution footcandles (fc)

Electrical power consumption Watts (W)

Luminaire aesthetics


Potentially Important

Price

Lifetime hours

Operating temperature °°°°C

Color temperature K CCT

CRI

Form factor

Ease of installation

Example CFL Down Light Characterization

Importance Characteristic Unit Value

Critical

Luminous flux lumens (lm) 1800

Illuminance distribution Lux (lm/m2) (defined in IES file)

Electrical power consumption Watts (W) 23 (excluding ballast)

Lifetime hours 10,000


ImportantColor temperature K CCT 4,000

CRI 75

Form factor 6 inch diameter can

Example Downlight: Critical Characteristics

InstalledCeilingHeight

Fixture :Flux (lm)Power (W)


IlluminanceDistribution

Example CFL Downlight IES File

What is an IES file?• It is basically the measurement of the far field distribution of light source (intensity) stored in ASCII format.

1800 Source lumens3 M Mounting Height


3 M Mounting Height89 Lux peak (~40 Lux ave)73% Luminaire EfficiencySpecular Reflector26W total power

2) Define SSL Design Goals

? How will this new (LED) product create value?

Value:• Same amount of light• Same quality of light• Longer lifetime without maintenance


Critical:• Same or more light• Same or more homogenous

distribution of light• Same or lower power

consumption

Important:• Same quality of light (CCT & CRI)• Same ambient temp rating• Longer lifetime

SSL Design Goals to Replace CFL Down Light

Importance Characteristic Unit Value

Critical

Luminous flux lumens (lm) 1800

Illuminance distribution Lux Same as example

Electrical power consumption Watts (W) 23 (excluding driver)

Lifetime hours 50,000


Important

Color temperature K CCT 4,000

CRI 75

Form factor 6 inch diameter can

Operating temperature °°°°C 55

3) Estimate Efficiencies of Subsystems

Electrical

?What kind of losses need to be taken into account?

What design solutions will best minimize these losses?

Design Goals


LEDSpecsThermal

Optical

• 1800 lm flux

• 23 W power

• 50,000 hour lifetime

• 4,000K CCT

• 75 CRI

• 55°°°°C max temp.

Optical Losses : LED Light is Directional

90° beam angle

High Power LED• One big advantage LED light has

compared to conventional bulb lights is that LED lamps send light in one direction

• If an intended application only needs to send light in one direction, keep in mind only some of the total light output will be useful.


• Other light will be lost to the reflector or sent in a non-useful direction in spite of the reflector.

• Secondary optics will be needed if LED beam angle does not meet the application requirements.

Conventional Lighting

Reflecto

r

Sources of Optical Loss

Reflector Coefficient of Utilization

Secondary Optics


Lens

85%-90% Efficient Varies

LED Secondary Optics

Secondary optics are used to modify the output beam of the LED such that the output beam of the finished lamp will efficiently meet the desired photometric specification.

LED optics can be categorized into:

• Reflectors

• Lenses

• Combinations of lens or reflector


The basic functions of the secondary optics are:

Diverging: Spread the emitted light

Colliminating : Colliminating the light into a narrower beam.

• Combinations of lens or reflector

Generally speaking, lenses are more

efficient in shaping the beam than

reflectors.


Diverging (diffusing): Spreads the light in a wider pattern


Spatial Radiation Pattern for LED only

0

0.2

0.4

0.6

0.8

1

-100 -50 0 50 100

Angle (º)

Rel

ativ

e In

tens

ity

Spatial Radiation Pattern for LED with Secondary Optics

0.0

0.2

0.4

0.6

0.8

1.0

-100 -50 0 50 100

Angle (º)R

elat

ive

Inte

nsity

LED with secondary optics


Colliminating: Focus the wide beam to narrower beam

Reflector

LensTIR LensReflector + Lens



0

0.2

0.4

0.6

0.8

1

-100 -50 0 50 100

Angle (º)

Rel

ativ

e In

ten

sity

Spatial Radiation Pattern for LED with Secondary Optics

0

0.2

0.4

0.6

0.8

1

-100 -50 0 50 100

Angle (º)

Rel

ativ

e In

tens

ity


Reflectors Overview

• Use reflective surface to collimate the LED light output

• Have a relatively large opening and some part of the light will never hit the surface and become unmanaged (called spillover)

• The result of spillover is a large area of scattered light around the main beam spot

• Are easy to make and relatively inexpensive

Spillover


inexpensive

• The shape of the reflector determines beam forming− Parabolic: gathers emitting light from the focal point and redirects as

parallel beam

− Aspheric: directs light in wider angles, providing general flood lighting

• The bigger the reflector, the better the beam control will be

• The smaller the optical source size, the better a reflector can control the beam

Total Internal Reflection (TIR) Overview

• Manages both direct and reflected light

• Light travels through at least 2 surfaces (often more), before getting out of the system

• Can be efficient even the size is small

• Relatively expensive compared to reflector


Use these surfaces to further shape beam pattern

Parabolic or elliptical shape to direct light

Collimating Lens in front of LED

Maximum efficiency when this ray is directed to edge of outer surface

Use these surfaces to further shape beam pattern







Typical Off-The-Shelf LED Secondary Optics



0

0.2

0.4

0.6

0.8

1

-100 -50 0 50 100

Angle (º)

Rel

ativ

e In

ten

sity


Example: 6 deg spot beam

Special LED Secondary Optics

Special optics (like street light, parking lot lens): Convert the lambertian beam from LED to specific distribution needed for unique applications



0

0.2

0.4

0.6

0.8

1

-100 -50 0 50 100

Angle (º)

Rel

ativ

e In

ten

sity


Potential Downlight Optical Solution

Use wide beam TIP optics to achieve best efficiency and control• Slightly more narrow beam

Reduces total lumens required to achieve same illuminance

Only 700 Source lumens3 M Mounting Height100 Lux peak (~40 Lux ave)90% Optical Efficiency


Ledil LXP Wide

Thermal Losses

Unlike traditional bulbs, light is emitted in one direction and heat goes out the other


Unlike traditional 5mm LEDs, power LEDs have separate paths for electrical & heat flow

Where is the LED Junction?


LED Junction

• LED junction is located within the LED package• LED junction temperature (Tj) cannot be measured di rectly

High Power LED Thermal Resistance

Thermal resistance quantifies how easily heat flows between the LED junction and the LED’s thermal path.

• Lower thermal resistance = better thermal flow

j

How to Measure Junction Temperature1. Wait for LED(s) to reach thermal

equilibrium2. Measure solder point temperature


j

sp

Rth j-sp: Thermal resistance between junction (j) a nd solder-point (sp)• Unit: °°°°C/W or Kelvin/W• Lower Rth j-sp = lower temperature difference betwe en j & sp

2. Measure solder point temperature3. Measure voltage & current4. Calculate power & Tj

Tj = Tsp + Rth j-sp * Power

Thermal Losses

Light output vs. increased junction temperature Tj


LED Junction Temperature vs. Lifetime

• Tj affects LED lifetime & long-term lumen maintenance

Tj (°°°°C) L70


X 51,000 hrs

X + 10 44,000 hrs

X + 20 38,000 hrs

LED Junction temperature vs Forward Voltage

• Temperature coefficient of Voltage

– -mV/°°°°C

• As the Junction temperature increases the forward voltage decreases.

Example: 10 LEDs in series


Vf @ Tj 25°C = 3.3V

Total voltage = 10 * 3.3 = 33V

After warm up Tj = 60 °C

Vf = 3.3 –(.004*35) = 3.16V

Total Voltage = 10*3.16 = 31.6

This example shows that using a constant current driver is very important.

LED Junction temperature vs Wavelength/CCT

As the Junction temperature increases, wavelength or CCT can shift

2

Rela

tive Intensity Color K

(nm/ºC)

Amber

.09


0

1

570 580 590 600 610 620 630

Wavelength [nm]

Rela

tive Intensity

Amber

Red

.03

Blue

.04

Green

.04

Cyan .04

Heatsink Selection/Design

• Manage heat to maximize performance

– Integrate heatsink into fixture housing

– Used thermal pads, tapes … to achieve best coupling between PCB and heatsink


PCB and heatsink

– Retrofits may not perform well

– Run thermal simulation to determine heatsink Rth required

– Select proper PCB material, size, shape to maximize heat transfer to ambient (lowest Rth)

Typical Power LEDs with MCPCB

Cu top layer35 – 70 µm

• MCPCB Advantages

– Low Thermal Resistance

– High reliability (rigid)

• But can be expensive


Metal Clad Substrate

Dielectric layer70 – 200 micronσ = 0.3 – 3 W/mK

35 – 70 µm

XLamp Does Work with FR4 too

+ -

+ -

XLamp

FR4

Isolated thermal path(electrically neutral)

SeriesLED

Circuit


Copper Plane(50-70 um)

Copper Thermal Vias

FR4

• With its isolated thermal path, XLamp does not have any problem with shorting through the thermal plane

• FR4 is easy for all manufacturers, can achieve low Rth

Electrical Losses

70

75

80

85

90

Efficiency (%)


60

65

70

0 20 40 60 80 100

Output Load (%)

Efficiency (%)

Generally, 85% - 90% is a good estimate for LED driv ers, except for high ambient temps or long lifetime

LED Drivers

Why do XLamp LEDs need drivers?

• Light output is a function of current

– To supply constant current to the LEDs

• LEDs are low voltage devices


– To transform AC to LED low voltage DC

– High voltage DC to LED low voltage DC

• To protect the LEDs from being overdriven and from transient voltages

• Provide accurate dimming control

LED Electrical Design

Goal: Control light output of LED system

• LED light output varies with current

200

250

Relative Intensity (%)


0

50

100

150

0 200 400 600 800 1000

Forward Current (mA)

Relative Intensity (%)

Voltage Variation in High Power LEDs

200

300

400

500

600

700

800

900

1000


Datasheet

LED1

LED2

LED3

LED4

LED5


0

100

200

2.5 3.0 3.5 4.0

Forward Voltage (V)


LED5

Vf to achieve If = 350 mA: 3.2 V – 3.4 V

• Every LED lamp has a slightly different relationshi p between voltage & current

• Very few parts perform exactly as shown on the data sheet

Voltage Variation in High Power LEDs

400

500

600

700

800

900

1000


Datasheet

LED1

LED2

LED3

Why is constant current drive important?


0

100

200

300

400

2.5 3.0 3.5 4.0

Forward Voltage (V)


LED3

LED4

LED5

If at Vf = 3.4 V: 350 mA – 675 mA

Result is relative LED brightness from 100% to 165% !Constant voltage drive is NOT recommended

Series Array

Advantages Disadvantages


• All LEDs at same current and same relative luminous flux

• Voltage increases linearly with number of LEDs in string

• One LED failing to open circuit will cause entire string to cease light output

Note: If Xlamp LED does ever fail due to internal c atastrophic or thermal issue, it will usually fail as short circui t

Series Array (With Zener Diodes)


Advantages

• All LEDs at same current and same relative luminous flux

• LED failing to open circuit will only affect one LED, not the entire string

Disadvantages

• Voltage increases linearly with number of LEDs in string

• Higher cost than Series Array

Parallel Array


Advantages

• Many LEDs powered from just one voltage drop

• One LED failing open will not affect any other LEDs

Disadvantages

• Potential for current hogging

• One LED failing to short circuit will cause the entire array to cease light output

Series-Parallel Array


Advantages

• Relationship between number of LEDs and voltage is configurable

• One LED failing to open circuit will only affect one LED string, not all LEDs

Disadvantages

• Resistors in each string waste power as heat, affecting the thermal design of the entire system

Constant Current LED Driver

Buck RegulatorAC-DC or DC-DC


Advantages

• Excellent current regulation

• High efficiency

• High power density

• Precise dimming capability

Disadvantages

• Higher relative cost

• More complex circuit design

• Possibly higher EMI

• Less common than constant-voltage

Dimming/Strobing LEDs

Pulse Width Modulation (PWM)

• Drive LED lamps at same peak current but at low duty cycle

• Eliminates matching problems from driving at low currents

• PWM frequency of at least 200 Hz

– < 70 Hz produces visible flicker,

– < 100 Hz: strobe effects of moving LED

– > 1000 Hz: possible EMC problems

• Best method for brightness control (dimming)


• Best method for brightness control (dimming)

• Applications– EVL Flashing, Beacon Strobing, Color Changing/Mixing

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 time(ms)

If DF=50% ton toff

Duty Factor (%) = t on/(ton+toff )*100

Constant Current Driver Selection

Modular vs. IC-based

Power Modules IC power solutions

Main Advantage

ready-to-use, fully tested smaller, more cost effective

Allowscustomers with no

electronics knowledge to Best dimming, flashing, and


Allows electronics knowledge to work with the LEDs

Best dimming, flashing, and color controlling

other Features

Dimming, UL & IP rated, wide VAC (120-277V) &

VDCin, high PF, up to 90% efficiency

Wide VAC (120-277V) & VDCin, >90% efficiency (DC

solutions), high PF

Ideal forPrototyping, low volume LED

applicationshigh volume production or if

custom drive is required

Driver Examples

AC-DC Module

DC-DC IC design


Other Driver Considerations

• Will drivers last for life of LEDs

– 50000 hours usable life

– Identify components at risk of early failure and substitute with longer life (cost, size, …)

– De-rate component specs accordingly for extreme operation conditions; improve reliability

• Does system require sealed driver (IP ratings)?


• Does system require sealed driver (IP ratings)?

• Is isolation required (for safety approvals)

Review of Subsystem Efficiencies

Subsystem Efficiency Type

Optical 90% Light

Thermal 85% Light

Electrical 87% Power


Only optical & thermal losses will affect the # of LEDs needed to meet the design goals

Electrical efficiency only affects the total “wall-p lug” efficiency of the luminaire

4) Determine Number of LEDs

? How do I calculate how many LEDs are needed?

• Calculate based on optical and thermal losses


OR for an easier method

• Use Cree Product Characterization Tool

� Register @ pct.cree.com/Register.asp

General Layout


Define the Desired Parameters


Select LED Type, Flux Bin and Temperature


• Be careful to select the bins that exist FOR THE CCT you are seeking (e.g. E7 kit, or 7B Bin, etc)

• Tj or Ts is usually an „Engineering Estimate“

Select Target Lumens and Efficiencies


Comparing the Calculations

• How does the XP-G compare to the XP-E when run at 500mA?


500mA?

• Second-highest bin selected.

Our Downlight Example Characterization


Delivered Efficacy

10 lm/W“17 lm/W”

Incand

Fixture Efficiency

58%x =

WARM WHITE

… Comparison to conventional sources


Optical Efficiency 85%

Driver Efficiency 85%

Thermal Equilibrium 88%*“80 lm/W” =

LED

xDelivered Efficacy

70 lm/W

Delivered Efficacy

35 lm/W

“60 lm/W”

CFL

Fixture Efficiency

58%x =

CA Title 24

xx

What Drive Current to Use?

Operating Current Pros Cons

Lower

• Higher efficacy (lm/W)

• Longer LED lifetime

• Better lumen maintenance

• Less flux per LED (more LEDs in system)

• Reduced efficacy (lm/W)


Higher• More flux per LED (fewer

LEDs in system)

• Reduced efficacy (lm/W)

• Reduced maximum ambient temperatureORDecreased lifetime

Decision on operating current should be driven by the design goals

Example down light = low drive current (350 mA)

LED Lifetime Is Irrelevant

System Design is What Creates Value, Quality

Driver : Currently the weakest point of the system, but the big companies are working on this

Heat Sink : Linchpin of the entire system. If this is poorly designed, all the other components can be compromised


LED Lamps : Practically never fail; depreciate very slowly in a well-designed system

Optical Components : Can (rarely) yellow over time and lose light; system design choice

companies are working on this

Quality Matters – Optical Design & Poor LEDs


Need Lighting-class LEDs

16.5” Lowes

Time zero

LED Puck

16.5” Linear

1000 hours

84.1% Drop

Quality Matters – Poor LED Selection


22” Linear

16.5” Linear97.8% Drop

96.9% Drop

Quality Matters – Driver & Thermal Problems

• Driver/circuit board failure


• Color Shift Due to poor thermal design

Generation 1 Generation 3

DriverCircuit(optional)

Generic LED Strip

Fixed Number of LEDs

Generation 2

Coping With Rapid Change in LED Performance

Modular Approach to MH Source Replacement


Generation 1 Generation 3Generation 2

A modular design approach can yield constant photometric output while facilitating ongoing cost reductions each time LED brightness is improved


Aim Ahead of the Duck…

LF Distribution


$X 1.2*$X0.8*$X

$X 1.2*$X0.8*$X

Prototyping with the highest performance LEDs curre ntly available is more expensive, but can yield a more competitive and longer life produc t over the long term


Plan for BOM savings

Generation 1 Generation 2


25% brighter LEDs can also mean 25% fewer LEDs. Ne ed to plan flexibility in your driver design to accomplish this

Design & Specification Strategies

Strategy #1 Strategy #2


• Insist on the tightest bin available

• Pay the highest price possible

• NOT a good approach

• Understand light, binning, and your application needs

• Do the mixing yourself in your fixture if the application will allow it

• Save money

LED Roadmaps


150

200

Effi

cacy

(lm

/W)

DOE Roadmap

Cree cool white production


0

50

100

2004 2006 2008 2010 2012 2014 2016 2018 2020

Year

Effi

cacy

(lm

/W)

Laboratory Projection - Cool White

Commercial Product Projection - Cool White

Commercial Product Projection - Warm White

Laboratory - Cool White

Commercial Product - Cool White

Commercial Product - Warm White

Maximum Efficacy - Warm White

Maximum Efficacy - Cool White

US Department of Energy 2009 Multi-Year Plan for SSL

Cree cool white production

Cree warm white production

How the Roadmap Really Works: Chip ImprovementLF @

350mA (lumens)

Current Generation100

150

Next Generation


• Major leaps forward on LF depends on major chip improvements

• Incremental chip improvements, phosphor efficiency, and learning curve historically improves 1-2 LF bins as well

Time

LF @

350mA (lumens)

Last Generation50

80

100

120

140

160

180

Light Source Efficiency Trends

Lum

ens/

wat

tLED Performance vs. Traditional Light Sources

LED

R&D Best

Linear Fluorescent

HID

Current LED

187


0

20

40

60

80

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Lum

ens/

wat

t

Incandescent

CFL

3 Years ago LED

Brightness/Efficacy Roadmap (XP-E Cool White)

122 (R3) / 112

130 (R4) / 120

Lumens / LPW*

139 (R5) / 128


2008 2009

114 (R2) / 105

2010

107 (Q5) / 99

* Mid-Point in Production

Oct 2009

Real LED Levels of Performance (2012)

6000K 4100K 3500K 2700KData Sheet LPW 165 136 136 107

Typical * Thermal Loss 10% 10% 10% 10%

Typical * Optical Loss 10% 10% 10% 10%

Typical * Driver Loss 15% 15% 15% 15%

Achievable * LPW 107 88 88 70

CRI ~75 ~80 ~82 ~83

* Typical with average/good design practices


• LEDs will be the most efficient mainstream source available

– >100 delivered LPW roadway light possible

– Indoor fixtures >80LPW (wall-plug)

* Typical with average/good design practices

Cree Support and Partnerships


Partnerships

Cree Support

Services Provided

• Cree XLamp expertise

• LED Design consulting

• Customized design

• LED engines

South America

GDE, Led do Brasil


• Turnkey solutions

• Sub-assemblyContact: Paulo Taminato

Cree Lighting Agent

Cree XLamp Solutions Partners

Secondary Optics

BrightView Technologies

Carclo

Fraen

G&L

Genius

ideaLED

Khatod

LEDiL

Drivers

Allegro

Austria microsystems

Infinilux

Intersil

Magtech

Maxim

Microchip

National Semiconductor


LEDiL

LedLink Optics

LTI Optics

Luminit

Polymer Optics

RPC Photonics

National Semiconductor

NXP

ON Semiconductor

ROHM Semiconductor

Zetex Semiconductors

Lists on Cree Website

Secondary Optics http://www.cree.com/products/xlamp_part.asp

Drivers http://www.cree.com/products/xlamp_drivers.asp

Cree Products Summary

XLampSingle Die White Multiple Die White




XR-C XR-E XP-E MC-E


Date post:	28-Jan-2015
Category:	Design
Upload:	claudio-pineda
View:	111 times
Download:	2 times