PowerPoint 프레젠테이션 - Seoul Semiconductor

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“A Company of Good People”
ACRICHE LIGHTING DESIGN GUIDE
- High-Bay Light (Factory Lamp) -
December 2010
www.seoulsemicon.com
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Contents
I.
Summary of Factory Lamp – Conventional Light Source
II.
LED Requirements for Replacing Conventional Light Source Factory
Lamps
III.
Target Setting
IV.
How to Select SSC PKG
V.
Considerations for Thermal, Optical or Electrical Selection
VI.
Supply Chain
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Ⅰ. Summary of Factory Lamp – Conventional Light Source
1. Factory Lighting
The purpose of factory lighting is to improve workability by creating a safe and pleasant working condition and contribute to
productivity by reducing the rejection rate.
The essentials of choosing factory lighting are to select light sources and equipment most suitable to factory conditions based on
analysis results such as job contents (precision, common), job objects (decision on the quality of light), working speed (foundation for
selecting light source), environment of the work place (reflectance, illumination factor), and work place building (height, room index,
equipment selection) and to plan lighting by sufficient review of the quality and quantity of light.
For a light source high intensity discharge lamps (HID) are mainly used, and the light source should be selected by considering the
efficiency, lifetime and quality of light. HIDs include high-pressure mercury lamps, metal halide lamps and high-pressure sodium lamps.
Ballast
High voltage generating circuit type (CC Type)
It consists of choke coil for stably lighting the lamp, an igniter circuit
voltage generating circuit for igniting the lamp and capacitor for improving
power factor.
Peak electrostatic force type (RC Type)
Since lead peak voltage is generated by a special iron core and
capacitors are connected in series to the secondary part of a leakage
transformer, the fluctuation rate is relatively good at 10% and the lamp is
easily ignited by a peak voltage of about 600 generated from the iron core.
Reflector
A reflector is mounted to adjust the beam angle of light source and
improve the light efficiency, and if a high-illuminance reflector is adopted,
a reflection efficiency of 85% or more is possible.
Lamp (HID)
These lamps usually use a high intensity discharge lamp, and include
high-pressure mercury lamps, metal halide lamps and high-pressure
sodium lamps.
< Fig.1 Incandescent Lamps structure >
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2. Types of Conventional Light Source Lamps (HID, High Intensity Discharge Lamp)
A high-intensity discharge lamp is a discharge lamp using luminescence by discharge of high-pressure gas or steam; it is a generic
term for high-pressure mercury lamps, metal halide lamps, and high-pressure sodium lamps, and they are called HID lamps for short.
High-pressure mercury lamps
High-pressure mercury lamps use luminescence by discharge in mercury steam of 0.2~1MPa
pressure. Color rendering and efficiency are improved by the use of a fluorescent material, so it is
widely used for general lighting such as in street lighting, factory lighting and sports lighting.
It is hard to start a high-pressure mercury lamp since the mercury steam lamp is high immediately
after it is turned off. The time taken to reignite after the luminous tube is cooled is called restart time.
KS specifies it to be within 10 minutes.
Metal halide lamps
Metal halide lamps are used as a light source not only for general lighting but also for copying,
photochemistry, plant breeding and fishing, as they use metal halogen compounds added to a highpressure mercury lamp to produce spectroscopic energy suited for widespread use.
Their lifetime is a little shorter because the tube edge temperature is higher than that of hightemperature mercury lamps, and identity characteristics are somewhat inferior, also the change in
lamp characteristics by variation of source voltage is large, and light color changes as well. The
efficiency is generally 70~80lm/W.
High-pressure sodium lamps
High-pressure sodium lamps are not eroded even by high-temperature alkali steam. It became
possible to manufacture sodium lamps thanks to the development of translucent high-density
polycrystal aluminum oxide. Among light sources for general lighting, these have a high efficiency
(140lm/W). With color rendering of an average of 5~30 at a color temperature of 2,000~2,100K,
they are inferior to fluorescent mercury lamps, but recently one has been produced with a color
rendering of 60 or more. They are suitable for outdoor lighting or lighting of factories or gymnasiums.
However, they have characteristics wherein the lamp voltage changes due to environmental
conditions such as source voltage and ambient temperature.
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Ⅱ. LED Requirements for Replacing Conventional Light Source Factory Lamps
1. Comparison of Conventional Light Source Characteristics
■ Comparison of Characteristics by Lamp Type
Classification
Metal Halide Lamp
High-Pressure
Mercury Lamp
High-Pressure
Sodium Lamp
Incandescent Lamp
Fluorescent Lamp
Capacity
(W)
35~3,000
40~3,000
20~1,000
2~1,000
6~110
Efficacy
(lm/W)
75~115
25~60
80~150
7~22
48~80
12K
16K~24K
20K
1K
10K
70
50
25
100
60~95
4,800
3,200~7,000
2,100
2,800
3,500~6,500
Takes 5~10 min.
Takes 5~10 min.
Takes 5~10 min.
Immediate ignition
Immediate ignition
300~400
300~400
300~400
-
-
30
30
30
-
-
Lifetime
(Hours)
Color Rendering
Index
(CRI)
Color Temperature
(CCT)
Ignitability
Heating
Temperature
(℃)
Mercury Content
(mg)
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2. Comparison of Specifications Between Conventional Light Source (HID) and LED Factory Lamps
■ Comparison of Light Efficiency between HID Lamps and LEDs
LED
Comparison Items
Light Source
Fixture
HID
Unit
AC LED
DC LED
Metal Halide
High-Pressure High-Pressure
Mercury
Sodium
Power Consumption
W
150
150
250
250
250
Total Luminous Flux
lm
12,000
16,000
19,000
11,800
25,000
Efficacy
lm/W
80
107
76
47
100
Total Fixture Efficiency
%
75
75
50
50
50
Total Luminous Flux
lm
9,000
12,000
9,500
5,900
12,500
Efficacy
lm/W
60
80
38
24
50
■ Light Loss in Fixture
Power
Terminal Loss
Power
Terminal Loss
╋
╋
Lamp Luminous
Flux Depleted
Heat Loss
╋
╋
Secondary Optic
Loss
Light Fixture Loss
50~60%
25~30%
[ LED ]
[ HID ]
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3. Requirements for LED Factory Lighting
■ KS Standard for LED Flood Lamp (KS_C_NEW_2010_0417 Prior
Notice Standard)
- Initial luminous flux: 95% or more of rated luminous flux
Classification
[K]
Color
Temperature
[K]
6,500
6,530 ± 510
Efficacy of
LED Light Fixture
[lm/W]
80
5,700
5,665 ± 355
75
5,000
5,028 ± 283
75
4,500
4,503 ± 243
75
4,000
3,985 ± 275
75
3,500
3,465 ± 245
75
3,000
3,045 ± 175
70
2,700
2,725 ± 145
70
- Color rendering index (CRI) : Ra 75 or higher
- Beam angle: 80% or more of rated luminous flux within indicated angle
- Efficacy of light fixture: 70~80 lm/W (See right table)
- Power factor: 0.9 or higher
- Luminous flux maintenance rate: 90% or more of the initial luminous flux
measurement value after 2000 hours aging
- IP grade : IP65 or higher
■ Adequate light distribution according to ceiling height of factory
Ceiling Height
Classification
Type of Light
Distribution
Light Distribution
Curve
5m or less
5m~10m
10m~15m
15m~20m
Back-lighting type
High-lighting type
Ultra-lighting type
Flood-lighting type
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Ⅲ. Target Setting
1. HID Lamp Replacing Target Setting
HID
No.
Subject
Symbol
Unit
SSC LED
Remarks
Metal Halide
Lamp
High-Pressure
Sodium Lamp
A4
A7
Z5
1
Power Consumption
P
W
250
250
170
184
130
2
Lamp Q’ty
-
PCS
1
1
170
46
114
3
Luminous Flux
F
lm
17,000
25,000
13,600
13,800
13,700
4
Power Efficiency
-
%
90
90
90
5
Secondary Optic Efficiency
-
%
90
90
90
6
Thermal Efficiency
-
%
90
90
90
7
Luminous Flux of Fixture
F
lm
8,500
12,500
10,000
10,000
10,000
8
Luminous Efficacy
F
lm/W
34
50
59
54
77
9
Color Temperature
CCT
Kelvin
4,800
2,100
5,700
5,700
5,700
10
Color Rendering Index
Ra
-
70
25
75
75
75
11
Beam Angle
FWHM
º
60
60
60
60
60
50
50
* When using A4-based 105 lm, light fixture efficacy of 75 lm/W or more is possible (2011.2Q estimated)
A4=80 lm
A7=300 lm
Z5=120 lm
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2. How to Determine the Number of LEDs
① First select lumen of target product.
② How to calculate lumen needed for LED to be implemented actually
.Actually needed Lumens = Target Lumens/(Optical Efficiency * Thermal Efficiency * Electrical Efficiency)
③ Select the number of LEDs
.Number of LEDs = Actually needed Lumens / Lumens of LED
ex) 1. Select HID 250W, and the Target Lumen is 10,000 lm.
2. Actually needed Lumens = Target Lumens/(Optical Efficiency * Thermal Efficiency * Electrical
Efficiency)
= 10,000 lm / (90% * 90% * 90%) =13,700 lm
3. Number of LEDs = Actually needed Lumens / Lumens of LED
= 13,700 lm /
80 lm = 170 LEDs
(@A4 PKG = 80 lm)
= 13,700 lm / 300 lm = 46 LEDs
(@A7 PKG = 300 lm)
= 13,700 lm / 120 lm = 114 LEDs
(@Z5 PKG = 120 lm)
■ Efficiency of light, thermal and electrical systems
System
Efficiency
Type
Optical
85~90 %
Reflector or Lens
Thermal
90 %
Al Heatsink
Electrical
90 %
Convertor or ADC
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Ⅳ. How to Select SSC PKG
1. Comparison Between Factory Lamp-Applied PKGs
■ Comparison of characteristics between factory lamp-applied PKGs
AC LED
Classification
DC LED
PKG Name
A4
A7
Z5
P4
PKG Power Consumption
[W]
1.0
4.0
1.12
1.12
PKG Luminous Flux
[lm]
80
300
120
110
PKG Quantity
[ea]
170
46
114
125
Module Luminous Flux
[lm]
13,600
13,800
13,680
13,750
Module Power Consumption
[W]
170
184
130
140
Optical Loss Applied
[lm]
12,240
12,420
12,312
12,375
Thermal Loss Applied
[lm]
11,016
11,178
11,080
11,137
Electrical Loss Applied
[lm]
9,914
10,060
9,972
10,023
CCT
K
5,700
5,700
5,700
5,700
CRI
Ra
75
75
75
75
LED PKG
Module
Finished
Product
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Ⅴ. Considerations for Thermal, Optical or Electrical Selection
1. Light Loss in LED
■ Thermal Loss
In LEDs, the quantity of light decreases according to junction temperature.
In general, the quantity of light written on specifications is that at Tj=25, and the LED
light quantity decrease rate according to Tj is also marked on specifications.
(See Fig.4).
Therefore, the quantity of light should be calculated by considering the Tj of an LED
that was actually installed in a module when manufacturing an LED lighting fixture.
Tj=70℃, 90%
Ex) If Tj measured (calculated) after applying a Z5 Cool White LED to a product was
70℃, the actual quantity of light is
120 lm*0.9 (luminous efficiency at Tj=70℃) = 108 lm. (@If=350mA, Ta=25℃)
■ Optical Loss
Most lighting equipments using LEDs use secondary optics to change the light
distribution pattern. In general, the efficiency of secondary optics is 85~90%.
And light is also lost by the fixture of lighting equipment such as a reflector.
However, because LED lighting has a luminescence pattern which is narrower than
conventional lighting such as common CFL so that the portion matching the fixture
is relatively small, loss due to fixtures is less than conventional light sources.
< Fig.4 Junction Temperature vs Relative Light Output >
Output 50%
■ Electrical Loss
Most driver efficiencies used in LED lighting equipment do not reach 100%.
Because such driver efficiency affects the decrease of efficacy of the overall lighting
equipment, this should be considered in designing an LED lighting system. The
driver efficiency is usually 80~90%, and if it is to be more than 90% the cost
increases.
And the efficiency of a converter differs according to output load. For low-cost
driver design, an output load should be at least 50% or higher. (See Fig. 5).
< Fig.5 Efficiency vs Output Load >
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2. Designing the Heat Sink
- Lowering Tj through heat sink can minimize the decrease of lifetime and luminous flux.
- Considerations in designing the heat sink
: Quality of the material of heat sink
Angle, fin thickness, and gap of heat sink
Relative Light Output [%]
Example of light output according to Tj
100
Lifetime
80
Luminous flux
Allowable current
60
∝
1
Tj
40
20
0
20
Pure White
40
60
80
100
120
o
Junction Temperature, TJ [ C]
140
It is important to lower Tj through heat sink
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■ Heat sink simulation
- Source
① LED : A7 PKG 40ea
② Power Consumption : 3.8W * 40ea = 152W
- Thermal conductivity by material
① Heat sink : AL(160 W/mk)
② PCB : MCPCB 1.6t (190 W/mK)
③ TIM(Thermal Interface Material) : 0.5t (3 W/mK)
- Heat sink specifications
① Size : Φ450 * 122mm
② Surface Area : 0.97㎡
③ Weight : 5.6kg
- Ambient temperature conditions
① Ta = 25℃
② Ta = 50℃
* Ceiling temperature of factory in summertime could well rise above 50℃
according to factory site.
Therefore, it is necessary to design heat sink under condition of Ta temperature
50℃, and the chip junction temperature of LED should be maintained at or above
90% of thermal efficiency.
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■ Heat sink simulation results
[Ambient temperature 50℃ condition]
AmbientTemp : 50℃
Heatsink Temp (Max) : 82.5℃
Chip Jungtion Temp(Tj) : 86.7℃
[Ambient temperature 25℃
condition]
AmbientTemp : 25℃
Heatsink Temp (Max) : 57.5℃
Chip Jungtion Temp(Tj) : 61.6℃
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3. Secondary Optic Design
Adjust beam angle and secure quantity of light through secondary optic.
Secondary optic considerations
: Shape, beam angle and light loss in joining with LED
■ Secondary Optic Types
Reflector type
Collimator type
Fresnel Lens type
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■ Reflector Design (Beam Angle 60˚)
<Directional Pattern Simulation,
60deg>
<Size>
φ16
[A4 PKG
Applied]
12.55
φ7
φ16
[A7 PKG
Applied]
12.55
φ8
<Group Reflector>
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■ Light distribution measurement results
- 60deg based on FWHM
[Polar Luminous Intensity Distribution]
[Cartesian Luminous Intensity Distribution]
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[Illuminance Greyscale Diagram]
[IsoLux 3D]
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■ A4 PKG Collimator type simulation
<Receiver Position>
<Simulation Data>
A4_Warm White_LED Only
1.2
1
0.8
%
0.6
0.4
0.2
0
-80 -70 -60 -50 -40 -30 -20 -10
0
10
20
30
40
50
60
70
80
Degree
1) LED Only
: 44.14 lm, 131 deg.
On-Axis Point
Intensity(50%) Point
A4_Warm White_38D Lens
1.2
Source ~ Screen Distance : 1,000 mm
1
Reciever Size : 1,000mm X 1,000mm
0.8
%
0.6
0.4
0.2
0
-50
2) LED + Lens
Æ 37.38 lm, 38 deg.
-40
-30
-20
-10
0
Degree
10
20
30
40
50
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■ Measurement Data (Initial Luminous Flux, Beam Angle)
(Source ~ Screen Distance : 1,000 mm)
<Simulation>
<Measurement Data>
LED Only
LED + Lens
LED Only
Simulation Data
LED Only
LED + Lens
Luminous Flux
44.14 lm
37.38 lm
Beam Angle
131 deg.
38 deg.
Æ Simulation Efficiency (Lens / LED) : 85%
LED + Lens
Measurement Data
LED Only
LED + Lens
Luminous Flux
48.66 lm
44.49 lm
Beam Angle
129 deg.
40 deg.
Æ Measurement Efficiency (Lens / LED) : 91.4%
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5. Electrical Considerations
1. Troubleshooting
Trouble
Electrical Trouble
Troubleshooting
Overvoltage
Use Zener Diode, TVS, MOV
Not lighted/decreasing
brightness
Overcurrent
Use PTC, NTC
Dielectric breakdown
Secure Pcb Pattern distance, insulation coating,
instrumental method
Acriche afterglow
Acriche afterglow
Connect S/W for contacts, use resistance
2. Overvoltage Protection
2.1 Causes of overvoltage
=> ESD (Electrostatic discharge), lighting surge, transient voltage, switching of load in power circuits, etc...
Item
Zener diode
TVS
MOV
Direction
Uni-directional
Bi-directional
Bi-directional
Supply voltage
DC
DC/AC
DC/AC
Response time
Tens of ps
Tens of ps
10-20 ns
Fig. 14
Fig. 15
Fig. 16
Symbol
I-V characteristic
Application
* TVS : Transient Voltage Suppressor
* MOV : Metal Oxide Varistor(Variable Resistor)
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2.1.1. Zener diode protection
(a) Zener diode I-V Characteristic
(b) LED protection operation
< Fig 17. Example of zener protection >
-Operating Principle
=> If overvoltage is applied from power supply, overcurrent is bypassed through a zener diode due to zener yield action and
regulated voltage of Vz is applied to an LED to protect the LED.
=> Since zener diode protection is the simplest and most basic way for protecting an LED from overvoltage, it cannot protect an
LED perfectly from all outside overvoltage. -> There is a need to construct additional protection circuit.
-Considerations when selecting zener diode
=> Use an element that has a Vz higher than the VF of the LED
=> Select an element that has adequate rated voltage considering VF, IF and service voltage of the LED
=> Select an element that has a low zener resistance for quick bypass action
=> Select an element that has high a current density as possible if drive current of the LED is great
=> Low leakage current
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2.1.2. TVS protection
(a) TVS I-V Characteristic
(b) TVS clamping
(c) TVS protection circuit
< Fig 18. Example of TVS protection >
-Operating Principle
=> A structure with a zener diode combined in both directions, it is a protection element using avalanche breakdown.
=> A bi-directional element may be used at an AC connection terminal and a DC uni-directional element may be used at a DC
connection terminal.
-Considerations for TVS selection
=> Use an element that has a VBR value higher than the VF of the LED
=> Select an element that has an adequate rated power considering VF, IF and service voltage of the LED
=> Select an element that has a clamping voltage value (Vc) less than the breakdown voltage of the LED
(If an element has a Vc of more than the LED breakdown voltage it cannot protect the LED from outside overvoltage)
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2.1.3. MOV protection
(a) MOV I-V characteristic
(b) MOV equivalent model
(c) MOV protection circuit
< Fig 19. Example of MOV protection >
- Operating principle
=> Carry out overvoltage function identical to TVS.
=> During normal operation, it has an insulation resistance value of more than hundreds of MΩ as a capacitor, but if
instantaneous overvoltage is applied, it becomes a conductor of less than tens of MΩ and bypasses overcurrent.
-Considerations for MOV selection
=> Use an element which has a VB value higher than the VF of the LED
=> Select an element that has an adequate rated power considering VF, IF and service voltage of the LED
=> Recommended to use to prevent inflow of current that exceeds the rated capacity of an MOV
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2.2 Overcurrent Protection
2.2.1 PTC (Positive Temperature Coefficient) resistor protection
-Operating principle
=> An element that has a characteristic that when the temperature of the element rises the resistance value increases greatly.
=> If a greater than rated current flows in a PTC, the resistance value increases greatly due to a self-heating action to carry out
the function of suppressing overcurrent.
=> Series connection to an LED suppresses overcurrent flowing in the LED.
(a) PTC Connection
(b) Resistance-Temperature Characteristic (R-T Characteristic)
< Fig 20. Example of PTC protection >
- Considerations for PTC selection
=> Select a PTC considering maximum voltage, maximum current, and maximum Ta of the LED
=> Select an element that has quick current suppression response time of the PTC
(c) Current Attenuation Characteristic
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2.2.2 NTC (Negative Temperature Coefficient) resistor protection
In-rush current level
- Operating principle
=> Use it to protect an LED from in-rush current
=> In-rush current can be generated during boost action and initial power-up action in power supply, and the LED
can be broken without proper protection measures.
=> Suppress in-rush current by series connection to the LED
(a) PTC Connection
(b) In-rush current suppression characteristic
< Fig 21. Example of NTC protection >
- Considerations for NTC selection
=> NTC is largely of two types of high resistance and low resistance, of which low resistance NTC is mainly used for in-rush current
protection
=> Maximum allowable current / power of NTC
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3. How to Reinforce Dielectric Strength
3.1 Cause of dielectric strength decrease
When the Cu pattern of a PCB is close to the PCB edge or PCB hole, the distance to metal heat sink or metal part of the PCB becomes
closer to cause electric discharge, so electric current could flow between the heat sink and terminal if a high voltage is applied.
Discharge at PCB edge
Discharge at PCB hole
Discharge at PCB Edge
( PCB Pattern ↔ PCB Metal)
( PCB Pattern ↔ PCB Metal)
(PCB Pattern ↔ Metal Heat sink)
Cu Pattern
PCB Metal
Wire connection PCB hole
Heat sink
PCB
insulation
layer
< Fig 23. Illustration of coating method >
< Fig 22. Analysis of dielectric strength decrease factors >
3.2 How to improve dielectric strength
- Keep a constant distance from a PCB edge or hole when designing the pattern of the PCB
To improve dielectric strength, keep the Cu pattern of a PCB a constant distance from the PCB edge or
PCB hole.
A distance of at least 5mm should be maintained to obtain a result of 4kV or more, and this may be changed
according to customer design specification.
(Coat the discharge portion
- Coat a PCB with insulating material
with insulating material)
Electricity is discharged usually at the PCB edge or hole which is close to the Cu pattern, so by coating this
portion with insulating material, dielectric strength can be improved. It is preferable to choose a material with
excellent thermal endurance and chemical resistance and a material that does not generate by-products
such as gas that affects an LED sealing material. (See Fig. 23).
- Insulate heat sink by installing a PCB in a case made of insulating material
Make the case with an insulating material and install a PCB in it to completely insulate the heat sink.
If a material that does not discharge heat well is used, it should be designed in such a way that heat
discharge can be maintained smoothly by minimizing the thickness considering Tj of the LED PKG.
< Fig 24. Illustration of PCB Case Concept >
(See Fig. 24).
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4. How to Improve on Acriche (A3) Afterglow
4.1 Phenomenon
- Acriche lamps do not completely turn off but emit weak light when the lighting integration switch is turned off after the
Acriche-applied lighting module (bulb, MR, PAR, etc.) has been installed in a building.
4.2 Cause
This happens when the switch is connected to the N phase in a 380Vac 3-phase 4-line wiring in a building and the case
(heat sink) of the lighting module is connected to F.G. (flame ground).
→ In most buildings, in the case of a lighting module being connected to F.G. in the building. F.G. is connected to the
N phase in most cases.
→ In such a case, even if the switch is off, phase voltage strays in Acriche lamps by F.G. connected to the case of the
lighting module, so afterglow occurs.
(Voltage straying in Acriche lamps ~ 130Vac)
Afterglow
S/W
. Phase voltage in 3-phase 4-line Y wiring – 380Vac
. Voltage between phase(R, S, T) and N – 220Vac
< Fig 25. ACRICHE applied voltage test diagram >
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4.3 Improvement scheme
4.3.1 Connect S/W to L(R) phase or connect L-N two-contact S/W
S/W
S/W
- Connect S/W to L phase so that remaining voltage does
not apply to Acriche when S/W is turned off.
- Use L-N two-contact S/W if it is difficult to connect S/W to L(R)
phase.
< Fig 27. ACRICHE Improvement Scheme #2 >
< Fig 26. ACRICHE Improvement Scheme #1 >
4.3.2 Distribute voltage remaining in Acriche using resistance
- Increase an MCPCB insulation resistance to divide the voltage applied to
the Acriche with the MCPCB insulation resistance to remove the remaining
light (when the S/W is turned off)
- Connect Rp in parallel to both ends of the Acriche to divide the remaining
voltage to remove afterglow (when the S/W is turned off)
: More than several MΩ
< Fig 28. ACRICHE Improvement Scheme #3 >
APCPCWM_4828539:WP_0000001WP_000000
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Ⅵ. SUPPLY CHAIN
■ Seoul Semiconductor Supply Chain
Ledlink (Taiwan)
IMS (USA)
Carclo (EU)
Gaggione (EU)
Khatod (EU)
LEDIL (EU)
Polymer Optics (EU)
Microblock (Taiwan)
LENS
DRIVER IC
Kaieryue Electronics Technology (China)
Microchip (USA)
National Semiconductor (USA)
Wai Tat Electronics (China)
Shenzhen Likeda (China)
Donghaw IND (Korea)
Green Optics (Korea)
SSC
Pttc(Taiwan)
Fela(EU)
Sekonix (Korea)
PCB
Xingtongbu Technology (China)
CCI (Taiwan)
Inno Flex (Korea)
DDP (USA)
Fujipoly (USA)
Ceramtec (EU)
Fischer Elektronic (EU)
Jindingli (China)
Yongshenkeji (China)
GK Technik (EU)
HEATSINK