LED Lighting Explained Workshop, May 15th 2013 -...
Transcript of LED Lighting Explained Workshop, May 15th 2013 -...
IEEE Santa Clara Valley Chapter, Components, Packaging and Manufacturing Technology Society
May 15, 2013
www.cpmt.org/scv
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LED Lighting ExplainedWorkshop, May 15th 2013
Seng-Hup TeohSenior Application EngineerPhilips Lumileds Lighting Company
Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
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May 15, 2013
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Evolution of Lighting
• Nuclear reaction
• Chemical reaction (combustion)
• Resistive heating (incandescent)
• Gas discharge (fluorescent, high pressure sodium lamp,metal halide)
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• Electroluminescence (light emitting diodes, LED)
Important Timeline of Light Emitting Diodes (LEDs)1962 First visible spectrum LED invented by American Nick Holonyak at GE in
Syracuse, NY. LED is in red spectrum, based on GaAsP epitaxial layer on GaAssubstrate.substrate.
1967 George Craford invented first yellow and orange LEDs while in Monsanto using GaAsP epitaxial layer on GaAs substrate. In addition, these LEDs have improved brightness performance with the use on nitrogen doped GaAsP epitaxial layer.
1980s Commercialization of AlGaAs LEDs1990 Hewlett-Packard commercializes AlInGaP LEDs1995 Japan Shuji Nakamura (Nichia) developed high brightness InGaN LEDs (blue) and
white LEDs with the use of phosphor.1998 Lumileds launched the first 1W high power amber, red-orange and red AlInGaP
LED (LUXEON I) Introduction of “high power” LEDs to market
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LED (LUXEON I). Introduction of high power LEDs to market2011 Philips wins DOE L Prize for A19 60W retrofit bulb for general use. L Prize 60W
bulb must be more than 90 lm/W, operating with less than 10W with minimum of 25,000-hour life at 2700K-3000K, 90 CRI
IEEE Santa Clara Valley Chapter, Components, Packaging and Manufacturing Technology Society
May 15, 2013
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FixtureFixture
Light EngineLight Engine
LevelLevel
00LevelLevel
44LevelLevel
33LevelLevel
22LevelLevel
11LED Systems
LED ArrayLED Array
LEDLED
DiDi
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DieDie
Presentation Outline
• Light, History & Overview of LED system• LED Technology LevelLevel LevelLevelLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
00LevelLevel
33LevelLevel
22
11
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
LevelLevel
44
3322LevelLevel
33
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Electrons
Photons
phQ
N
LevelLevel
00Simplified LED operation
--
--
--
-
Electronse
Q N
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Heat
Photon Energy and Wavelength LevelLevel
00
λ
hc
E ph
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Higher photon energy
Lower photon energy
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LED Illustration
- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -
“Bandgap Eg”
p‐layer n‐layer
LevelLevel
00
- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -
- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -
Bandgap Eg
hc
E ph
junction
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LED Material System - AlInGaP LevelLevel
00
AlInGaP
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LED Material System - InGaN LevelLevel
00
InGaN
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How Different Colors Are Produced?
p‐layer n‐layer
LevelLevel
00
- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -
- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -- - - - - - - - - - - - - -
Change bandgap, Eg
•Aluminum Indium Gallium Phosphide, (AlxGa1-x )0.5In0.5P
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•Indium Gallium Nitride, InxGa1-xN
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What About White?
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• Mix RGB LEDs
• Add phosphor material to blue LED
Phosphor – Basic Physics
Electroluminescence vs photoluminescence
Excited states
Green light emission
heat
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Blue light source
Ground state
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Phosphor Materials
Example of green/yellow phosphorYAG C (Y i Al i G- YAG:Ce (Yttrium Aluminum Garnet,
Cerium doped)- LuAG:Ce (Lutetium AluminiumGarnet, Cerium doped)
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Example of red phosphor - (SrxCa1-x)AlSiN3:Eu
“Rare” Earth Metals
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Example of Phosphor Emission Spectra Control
Spectra of (Sr Ca1 )AlSiN3:Eu phosphors as a function of Sr content xSpectra of (SrxCa1−x)AlSiN3:Eu phosphors as a function of Sr content, x
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Kim Y et al. ECS J. Solid State Sci. Technol. 2013;2:R3021-R3025
Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
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Typical LED Manufacturing Process
EpitaxyGrowth
Bin
1
Bin
2
Bin
N………
WaferFabrication
Test &Binning
Substrate B B B
Phosphor
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DiePreparation
Packaging
Epitaxy
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n‐contact
Epitaxy Growth & Wafer Fabrication
Sapphire Substrate
InGaN Active Layer
p‐contact
dielectric
p-GaN
n-GaN
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Epitaxial GrowthWafer
Fabrication
Die Preparation
• Testing
LevelLevel
00
DiePreparation
• Testing• Singulation• Visual Insp
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LevelLevel
11Level 1 Packaging
Light extraction
------ -
Electrical contacts
extraction
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Heat extraction
Mechanical support and protection
Level 1 Packaging
• Low Power (~0.1W) to Mid Power (~0.5W)
LevelLevel
11
• High Power (> 1W)
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Typical Level 1 LED Package Assembly
Die attachCeramic substrate“Goop” in a cup
LevelLevel
11
TVS/ESD
Dome
InGaN
Phosphor
Die attach-GGI -Eutectic/reflow bonding-Silver epoxy
Ceramic substratePCB rigid/flexCopper plated leadframe
Goop in a cupLaminateElectrophoresis depositionMoldingSlurry coating
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Ceramic Substrate
Typical LED Package Electrical Schematics
•AlInGaP is not susceptible to ESD damage+ve -ve
•InGaN chip is
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Binning
3
4
5
Flux
2
4
6
8
Color
0
1
2
3
4
5
A B C D E
Forward Voltage (Vf)
0
1
2
3
V W X Y Z
0
2
7A 7B 7C 7D 8A 8B 8C 8D
Color
Full Distribution
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Bin Code: XYZ or XYYZX = flux codeY = color codeZ = Vf code
Vf
Flux
Color
Freedom From Binning
Performance close to real operating condition
Tested “hot”, Tj = 85°C instead of 25°C
ANSI 3000K
ANSI 2700K
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
LED Performance Characteristics
Forward current
Junction Temperature
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Electrical Optical Reliability
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ForwardCurrentReverseCurrent
Current – Voltage in Both Forward & Reverse
LED is not
+
-
LED is not designed to be driven in reverse bias!
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ForwardReverse
Parametric Interrelationship
P = Vf * If
If T
Vf P
A °C
V W
Forward Current
Forward Voltage Dissipated Power
Junction Temperature
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Θlm
Luminous Flux
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What About Color?
Color parameters:• Peak wavelength (nm)Peak wavelength (nm)• Color points (cx, cy) in CIE 1931 color space or in (u’, v’) CIE 1976 color
space • Dominant wavelength (nm)
A °C
CnmV/50)(
dompeak
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Θcolor
CnmV/ 5.0T
Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
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There is no color in physics class
No Laws or Theorems
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400nm 800nm
It’s all in your head… Human perception
Human eyes response to brightness and color are experimentally based
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400nm 800nm
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Fun Stuff – Eye Tricks
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Visible Radio
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1800
Photopic Scotopic Mesopic
1800
1700lm/W at 507nm (Night)
400
600
800
1000
1200
1400
1600nous Efficacy (lumens/watt)
Photopic
683 lm/W at 555nm
400
600
800
1000
1200
1400
1600nous Efficacy (lumens/watt)
Photopic
Scotopic
683 lm/W at 555nm (Day)
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0
200
350 400 450 500 550 600 650 700 750
Lumin
Wavelength (nm)
0
200
350 400 450 500 550 600 650 700 750
Lumin
Wavelength (nm)
Photopic Eye Response (Luminosity Function, V(l) ) as Defined by CIE 1931
1.0
0.4
0.6
0.8
Norm
alized Response
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0.0
0.2
350 400 450 500 550 600 650 700 750 800
Wavelength (nm)
CIE (1931)
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Light Measurement - FLUX
Photometric Radiometric
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Flux symbol
Units Lumen (lm) Optical watts (Wopt)
Weightingfunction
V(λ) none
V E
Flux Calculation
• What’s needed?• Spectral Power Distribution (SPD) hcSpectral Power Distribution (SPD)
ibut
ion/
Pow
er
hc
E ph
E
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Photon Energy (Wavelength)
Dis
tri
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Flux Calculation (continue)
dVEV
780
380
683
d
780
Photometric Flux
Radioometric Flux
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1 W Radiant Flux at 555 nm = 683 lumens
dEE
380
Example: Photometric Flux for Blue and Green LEDs
• Blue and Green LEDs with one watt of optical power
780
dV EV
380
683
Total Power(Wopt)
Total Luminous Flux (lm)
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Blue LED 1.0 71
Green LED 1.0 515
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Color Measurements
• RECALL…• Peak wavelength (nm)g ( )• Color points (x, y) in CIE 1931 color space or in (u’, v’) CIE 1976 color space • Dominant wavelength (nm)
Let’s define these parameters
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Peak Wavelength
Peak wavelength (radiometric)
0 25
0.50
0.75
1.00
Sp
ectr
al P
ow
er (
W/n
m)
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0.00
0.25
380 400 420 440 460 480 500 520 540 560 580 600 620 640
wavelength (nm)
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Color Points
• Create color space
CIE 1931
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Another Color Space
CIE 1960
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Or Another One?
CIE 1976
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Last One?
Slice at L=50CIE 1976 L*a*b*
… and many more…..
= L
ight
ness
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L
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CIE 1931 Color Matching Functions
• Define human eye response to each red, green and blue stimuliy p , g
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CIE 1931 Color Definition
• Tristimulus X, Y, Z R, G, B
• Define red flux, green flux and blue flux.
X = e ()x () dY = e ()y () dZ = e ()z () d
Unit for X, Y and Z is lumen
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CIE 1931 Color Points (x, y)
• Define red, green and blue flux ratiox = X / (X + Y + Z)( )y = Y / (X + Y + Z)z = Z / (X + Y + Z)
• Normalizationx + y + z =1 (x, y) chromaticity color points in CIE 1931 color space
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• For more details, see “Wyszecki & Stiles (Wiley Series), Color Science: Concepts and Methods, Quantitative Data and Formulae”
The CIE 1931 xyY Color Space
Spectral locus
E = Equal energy point (0 3333 0 3333)
E
Monochromatic light, pure color
Create color bins
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(0.3333, 0.3333)
x yColor points
Black Body (Planckian) Locus
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Now We Can Finish of Dominant Wavelength Color Definition• Light of similar “hue”
• Color purity = a/b
C (x, y)
dom = 550nm
a b
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E (0.3333,0.3333)
b
CIE 1931 / CIE 1976 Color Space Conversion
1931
1976u’ = 4x / (-2x +12y +3)v’ = 9y / (-2x +12y +3)
x = 9u’ / (6u’ – 16v’ + 12)y = 4v’ / (6u’ – 16v’ + 12)
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Recap….
• Peak wavelength (nm)
• Color points (x, y) in CIE 1931 color space
• Dominant wavelength (nm)
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Other LED parameters to describe “white” color?
White Color
• Correlated Color Temperature (CCT, in K)
• Color Rendering Index (CRI, dimensionless, between 0 to 100)
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Color Temperature
Candle flame
Incandescent bulbr
tem
pera
ture
(K
)
Daylight
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Col
or
CORRELATED Color Temperature (CCT)
• Commonly used color bins for solid state lighting are defined in “ANSI ANSLG C78.377: Specifications for the Chromaticity of Solid State Lighting Products”
• 2700K, 3000K,3500K, 4000K 4500K
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4000K, 4500K, 5000K, 5700K & 6500K
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Color Rendering
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
LevelLevel
33LevelLevel
22
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
3322
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What to Consider When Building a LED System?LevelLevel
22
1) Thermal2) Electrical3) O ti
LevelLevel
33
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3) Optics
Thermal – Tungsten versus LED Bulb
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40 Watt Incandescent Philips 60W L Prize
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Electrical Blue Light Out PΘ = 0.35W
LED Power Efficiency
PowerIn
i i Q O i l
PE = 1W
Wall Plug Efficiency
Optical Power outElectrical Power In
=
(WPE)
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Manage this
ResistiveLosses17%
QuantumIn‐efficiency
42%
OpticalLoss6%
PTh = 0.65W
Research focus
Why You Need to Manage Thermal?
P = Vf * If
If T
Vf P
A °C
V W
Forward Current
Forward Voltage Dissipated Power
Junction Temperature
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Θlm
Luminous Flux
color LED Reliability
• As a general rule of thumb, design for thermal first
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Keep LED Junction Temperature Low. How?
1
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Thermal Resistance (Rth)
• Rth = (T1 – T2) / Pheat dissipationRth (T1 T2) / Pheat dissipation
• Unit in K/W or °C/W
Thermal Parameters Electrical Parameters
Resistance (K/W) Resistance (ohms)
Temperature difference (K) Potential difference (V)
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p ( ) ( )
Heat flow (W) Current flow (A)
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Typical LED System Stack
T
PCB
Solder paste
TIM
TJ
TPCB thermal pad
TPCB bottom
RthLED package
RthPCB
RthHeat sink
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Heat Sink
A M B I E N T
THeat sink bottom
TAmbient
Heat sink
RthHeat sink - ambient
Convection
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PCB Construction & Design LevelLevel
22
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Thermal Interface Material (TIM)
After adding TIMNo TIM
50.0°C
20
30
40
50
Max board temp = 47.8C@60 Minutes
After adding TIMMax board temp = 52.2C@60 Minutes
50.0°C
20
30
40
50
No TIM
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20.0°C20
20.0°C20
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Heat Sink
400
450Al: k=170
150
200
250
300
350 Copper: k=400
Silicon: k=148
Stainless Steel: k=16
C b St l k 60
OR
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Thermal Conductivity Units are in W/mK.0
50
100 Carbon Steel: k=60
Acrylic: k=0.180.4 K/W $$$$$$
40 K/W
Junction Temperature Measurement
• Use thermal resistance equipment
• Manufacturer’s application notes on Ts method (compare to IC, temperature characterization parameter, yJT )
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
Electrical – Current or Voltage Drivers?
• Recap
LevelLevel
33
LevelLevel
22
+VLED
-
ILED
600
800
1000
1200
1400
1600
ard Current (m
A)
At 3.00V, ILED = 870mA
33
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0
200
400
2.4 2.6 2.8 3 3.2 3.4 3.6
Forw
Forward Voltage (V)
At 3.15V, ILED = 1500mA
5% VLED ILED 72%!
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Consideration for Voltage Driver Design
ILED
1LEDS VRIVLED
VVI LEDS
LED1
1
R
VLED1
+
-
Vs+
-
RILED1
400
600
800
1000
1200
1400
1600
rward Current (m
A)
R = 10 ohmVs = 11.7V
400
600
800
1000
1200
1400
1600
rward Current (m
A) R = 10ohm
Vs = 12.285V
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• If R is large, ILED is insenstive to Vs fluctuation Disadvantage: very inefficient!
0
200
2.4 2.6 2.8 3 3.2 3.4 3.6For
Forward Voltage (V)
0
200
2.4 2.6 2.8 3 3.2 3.4 3.6For
Forward Voltage (V)
1600
Electrical – Series or Parallel?
Itotal
200
400
600
800
1000
1200
1400
Forw
ard Current (m
A) +
VLED
-
ILED1 ILED2
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0
200
2.4 2.6 2.8 3 3.2 3.4 3.6
Forward Voltage (V)
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Electrical Power Distribution – PCB Copper Trace Layout
50.0°C
20
30
40
5050.0°C
20
30
40
50
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20.0°C20
20.0°C20
Summary
• LEDs are best driven by current source
• Connecting LEDs in parallel is more challenging than in series
• In high current operation, PCB copper trace width and length need to be considered
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LED Drive System
Sources LED ArrayDriver
LevelLevel
33
V ▲▼
I
AC
DC If
Feedback
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Dat
a
Con
trol
LED Driver Types
Passive Active
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Linear
Mode
Switched
Mode
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Switch vs Linear Analogy
Regulator
Switch
Reservoir
Waste
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Linear Switched
Linear Regulator (Constant Current Regulator, CCR)
refVI
++
out
ffout
finin
sense
P
IVP
IVP
RI
+-
Vref
Rsense
Vin-
Vf
If
Vsense
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inPsense
-
Typical efficiency ~ 70%
Typical current variation ± 5% with Vin ±10%
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Switch Mode Regulators
Switch ModeSwitch Mode
DC-DC
B k
AC-DC
N
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Buck Boost Buck-Boost
Isolated Non-Isolated
Vout < Vin
Vout > Vin
Any Vin/Vout
Vout < Vin
Vout < Vin
Comparison
Linear Switch Mode
Cost Cheap ExpensiveCost Cheap Expensive
EMC No issue Potential
Circuitry Simple Complicated
Efficiency Low (~70%) High (75% .. 93%)
Size & Weight Larger and heavier Smaller and lighter
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Other Electrical Considerations
• Transients• SwitchingSwitching• Brownout• Lightning• Dimming (resistor vs triac control PWM)• Hipot testing• Power factor
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
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OpticsLevelLevel
33
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Basic Principles
• Refraction (Snell’s law)
• ReflectionReflection
• Absorption and Transmission
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Optical Design
1) Optical software simulation such as ASAP, LightTools, Zemax, TracePro, Photopiap
2) LED light source– Optical model creation using the above optical sofware– Measured rayset
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Rayset
Source imaging / Near-field goniophotometergo op oto ete- Radiant Zemax- TechnoTeam
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Optics Consideration
• Optical efficiency ~85%-90%• LED light source distributionLED light source distribution• LED apparent source size• Final optics size• Material selection (polycarbonate, PMMA, glass)• Fire safety consideration (UL)
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
LevelLevel
44LevelLevel
33
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Building a Lamp System or Luminaire – A19 BulbLevelLevel
33"2 8
3
"4 83
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1”
• Cost• Efficiency
A19 LED Bulb Assembly
Diffuser bulb/cover
LevelLevel
33
LED arrayTIM
White reflector
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Current driverAluminum heat sink
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A19 Sub-Components
Plastic housing, E26 screw & electrical contact pin
LED driverLED array board (shown without LUXEON LEDs and thermal interface material)
LED white reflector sheet
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Heat sink
Top metal bulb cover
Top reflector sheet
White reflector plastic tube & washer
bulb
Not shown or provided are glues/adhesives, potting material, solder and screws
Technical Evaluation
Energy Star Requirement
60W
LED Count -7up
LXH8 PW30LXH8-PW30
CCT ANSI 3000K
CRI 80 min 80 min
Lumens (min) 800 800
Lm/W 55 58
Beam Angle +/-135 within 20% of
avgYes
Lumen Maintenance
>70% (L70) 25Khrs>70% (L70)
25Khrs
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Input Voltage - 110 VAC
Bulb Power - 13.7W
Current - 575 mA
Driver - Marvell
Driver efficiency - >85%
Power Factor >0.7 >0.9
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Thermal
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Philips A19 60W L-Prize
•InGaN chip WPE improvement
•Remote phosphor
•Thermal design
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L-Prize vs Concept A19 (60W) Bulb Thermal Comparison
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Presentation Outline
• Light, History & Overview of LED system• LED TechnologyLED Technology
– Semiconductor physics: pn junction and phosphor– LED Manufacturing– LED Performance Characteristics
• Color Science• LED System Design Consideration
– Thermal– Electrical
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Electrical– Optical
• Building luminaries– A19 Bulb– Street Light
LevelLevel
44
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Street Light
• Regional standardsLighting distribution light pollution
LevelLevel
44• Lighting distribution, light pollution• Maintenance• Power efficiency• Cost• Lighting control
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Los Angeles before LED Retrofit project (2008)
1908 1988
2002
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Photo credit: City of Los Angeles, taken from Mount Wilson
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Los Angeles after LED Retrofit project (2012)
1908 1988
• 98,000 of the cities 210,000 streetlights moved to LED
2002
p: 105 / 115www.cpmt.org/scv LED lighting explained workshop. May 15th, 2013
Photo credit: City of Los Angeles, taken from Mount Wilson
LEDs Enable Superior Light Shaping Capability
1908 1988
2002
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Design Concept
565 mm
69 mm
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565 mm
229 mm
Design Concept
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• 12 LUXEON M and Ledil Strada optic
• PMMA Coverplate
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Cross section
p: 109 / 115www.cpmt.org/scv LED lighting explained workshop. May 15th, 2013
• Room for the Advance 150W outdoor driver• Hollow sections to save weight
Street Geometry and Performance Requirements Based on ME3a (European)
Surrounding area
Street geometry no overhang
no tilt
Street geometry:
- Road pavement: R3 classification
P l h i ht 8 t
30 m
7 m
Lamp Lamp
Street
8 m
7 m
Lighting class: ME3a
- Average luminance (Lavg): 1 Cd/m2
O ll if it (U ) 0 4
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- Pole height: 8 meter
- Pole distance: 30 meter
- Street width: 7 meter
- Number of lanes: 2
- Lamp overhang: 0 meter
- Lamp tilt angle: 0 degrees
- Placement: Single sided (unilateral)
- Overall uniformity (Uo): > 0.4
- Longitudinal uniformity (Ul): > 0.6
- Threshold increment (TI): < 15%
- Surround ratio (SR): ~ 0.5
- lumen maintenance = 0.8
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The Optics: Ledil Strada-SQ-A-T for LUXEON M
Secondary lens for LUXEON MType II intensity distribution
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Summary of System Characteristics Performance (20°C Ambient)
Parameters Performance
D i t 700 ADrive current 700mA
Total light output 10,756 lumens
Total LED power 95.7W
Lamp system efficacy 86.5 lm/W
Driver efficiency 85%
Optical efficiency luminaire 90%
Junction temperature 87 C
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Junction temperature 87 C
Heat sink temperature 50 C
Street performance: Meets the ME3a street light requirements.
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The EndQuestions?
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PHILIPS LUMILEDS LIGHTING COMPANY shall not be liable for any kind of loss of data or any other damages, direct, indirect or consequential, resulting from the use of the provided information and data. Although PHILIPS LUMILEDS LIGHTING COMPANY has attempted to provide the most accurate information and data, the materials and services information and data are provided “as is” and PHILIPS LUMILEDS LIGHTING COMPANY neither warranties, nor guarantees the contents and correctness of the provided information and data. PHILIPS LUMILEDS LIGHTING COMPANY reserves the right to make changes without notice. You as user agree to this disclaimer and user agreement with the download or use of the provided materials, information and data.
© Koninklijke Philips Electronics N.V., 2011. All rights reserved.