LED Manual PAGE 1
2
ITEM
Page
ITEM
Characteristics data ①
11
Reliability Data(Blue ,White LED)
(Relative luminous intensity x IF, Relative luminous intensity x Ta, IF x VR, Derating)
12
Sulfuration
13
Mechanical Strength
Characteristics data ② (Max peak current-Pulse width characteristics)
3
Luminous intensity criteria sample
14
Failure of Pick-up
4
Location of Chip
15
Cautions of Silicon Resin Sealed Products
5
Location of Chip, Viewing angle
16
Not Lighted on due to Moisture Absorption
6
About Luminous intensity and Luminous flux
17
Storage Conditions / Packing
7
Rth
18
RGB Chromaticity Classification of Mixed Lighting LED
8
LED operation circuit
9
Flow Temperature Profile
10
Reflow Temperature Profile
© 2018 ROHM Co.,Ltd.
Rev.003 Jan. 9, 2018
Characteristics data ① (Relative luminous intensity x IF, Relative luminous intensity x Ta, IF x VR, Derating)
Rohm LED specification includes following data
Ta=25℃
0.6
If Forward current(IF) is raised, luminous intensity becomes weak.
0.4 0.2 0.0
5 10 15 FORWARD CURRENT：IF(mA)
1 0.8 0.6
20
-40-30-20-10 0 10 20 30 40 50 60 70 80 90 100 ATMOSPHERE TEMPERATURE：Ta(℃)
30
10
Diode characteristics
MAXIMUM FORWARD
Ta=25℃
100
IF(mA)
1.2
0.4 0
FORWARD CURRENT：
INTENSITY
0.8
If temp. heating-up, re-united ratio of Electron & hole drops. Then, luminous intensity becomes weak.
1.4
CURRENT：(mA)
INTENSITY
1.0
IF=20mA
1.6 RELATIVE LUMINOUS
1.2
RELATIVE LUMINOUS
20
Current value should drop with consideration of Tj and temperature
10
0
1 1.0
© 2018 ROHM Co.,Ltd.
1.5 2.0 2.5 FORWARD VOLTAGE：VF(V)
3.0
-40-30-20-10 0 10 20 30 40 50 60 70 80 90 100 AMBIENT TEMPERATURE：Ta(℃)
P. 1
Characteristics data ② (Max peak current-Pulse width characteristics)
(Chart 1) Pulse width(x) 100Hz
200Hz
1kHz
2kHz
Pulse Duty ：x/z 10kHz
IF Max（Pulse）／IF Max(DC)
10
frequency：1/z
★
5
1 1
10
100 PULSE width : Tw(μs)
LED lighting time Frequency Pulse cycle Pulse Duty ①1÷ｙ＝ｚ ②ｘ÷（1÷ｙ）＝ A
：ｘ (sec.) ：ｙ (Hz) ：ｚ（sec.） ：A
1000
10000
Pulse cycle(ｚ)
（Ex.) LED lighting time ：1000μsec. Frequency :100Hz → Pulse cycle＝1/100=0.01sec.=10000μsec. Pulse Duty＝1000/10000=1/10 （Chart 1 ★） →IF Max(Pulse) is 5 times bigger than IF Max(DC).
IF Max(in case of Pulse duty10%) is 5 times bigger than IF Max(DC). Depending on the Pulse frequency and Duty used, IF Max(DC) limit is changed. To prevent the LED lights flickering, we recommend to use over 100Hz. © 2018 ROHM Co.,Ltd.
P. 2
Luminous intensity criteria sample (Current control luminous intensity sample)
Distribution of LED Luminous intensity rank is as Chart 1. Therefore, when check the criteria samples of upper and lower limits of luminous rank, we submit the current controlled samples. (You can have current controlled sample faster than actual limit sample.) Ex.) See Chart 2
By using 80mcd@20mA, lower limit sample of rank R(56mcd) is available with IF=20mA x 0.7 times condition.
56
RankQ
50
90 RankR
140 RankS
40 30
20 10 0 0
© 2018 ROHM Co.,Ltd.
20
40 60 80 100 120 140 Luminous intensity(mcd)
Luminous intensity(mcd)
36
60
Yield rate（％）
100
80mcd
80
56mcd
60 40 20 0 0
2
4
6
8 10 12 14 16 18 20 22 Current(mA)
P. 3
Location of Chip • Because LED needs the space for DB and WB, chip won’t always at the center of PKG.
【E.g.】
SML-P1* (R)series
SML-D1* series
Side-view LED SML-E1* series
SML-A1* series
（0.245ｍｍ） (0.11ｍｍ)
EXCELED™
(0.11ｍｍ) （0.11ｍｍ）
PICOLED®
（0.3ｍｍ） 0.3ｍｍ
center
© 2018 ROHM Co.,Ltd.
P. 4
(0.11ｍｍ)
Location of Chip, Viewing angle ［Location of Chip(Ex.)]
EXCELED™ SML-D1＊series
SML-E1＊series Location of Chip is at the center of PKG.
［Viewing angle]
Location of Chip isn’t at the center of PKG. X - Y
SCANNING ANGLE(deg)
X - Y
20
10
0
10
20
10
0
10
20 30
30
20
30
30 ｽｷｬﾝ方向 (Scanning Direction)
SCANNING ANGLE(deg) ｽｷｬﾝ方向 (Scanning Direction)
40
40
40
40
50
50
50
50
60
60 60
60
70
70 70
70
80
80 80
80
90 100
0
50
90 100
50
90 100
0
50
RELATIVE INTENSITY(%)
RELATIVE INTENSITY(%)
X' - Y'
SCANNING ANGLE(deg)
SCANNING ANGLE(deg)
X' - Y'
20 ｽｷｬﾝ方向 (Scanning Direction)
10
0
10
20 20
ｽｷｬﾝ方向 (Scanning Direction)
30
30
40
40
10
0
10
20
Luminous intensity near the chip is higher than other parts
30
30
40
40
50
50 50
50
60
60 60
60
70
70 70
70
80
80
80
80 90 100
90 100
50
50
0
50
90 100
90 100
50
RELATIVE INTENSITY(%)
0
50
90 100
RELATIVE INTENSITY(%)
• Because LED needs the space for DB and WB, chip won’t always at the center of PKG. • If the optical properties are important, please check the Viewing angle. © 2018 ROHM Co.,Ltd.
P. 5
About Luminous intensity and Luminous flux Luminous intensity :In photometry, a measure of the wavelength–weighted power emitted by a light source in a particular direction per unit solid angle. Unit is candela(cd). Luminous flux
: Brightness of whole light, emitted from light source. Unit is lumen(lm)
Luminous flux（lm）
Ex. SMLK1/K2 series 20 15 10 5 0
0
1
2
3
4
5
6
Luminous intensity（cd）
© 2018 ROHM Co.,Ltd.
P. 6
Rth (Thermal resistance) Tl :Terminal temperature
2 kinds of Rth exist. Junction to case(terminal) : Rth.(j-C) Junction to ambient : Rth.(j-a)
Heat-dissipation of surface mount device is thru PCB.Therefore, value of Rth(j-C) is measured Tl and calculated in Rohm PCB condition.
R1
Sub.
R2
Terminal temperature is measured on LED mounted side.
R1 = Rth(j-C) R1+R2 = Rth(j-C)+Rth(c-a) = Rth(j-a)
Ex) SML-D1 series PCB size
Rth (j-a)
Rth (j-C)
(mm)
(℃/W)
(℃/W)
Single Device
458
―
10 × 10
209
101
200
15 × 15
151
74
100
20 × 20
121
57
0
40 × 40
83
51
50 × 50
70
50
500
Rth（℃/W）
[P=IF × VF = 20mA×2.0V]
Tj=Tc + Rth(j-C)×P Rth(j-C) = Tj-Tc P
400 300
0
© 2018 ROHM Co.,Ltd.
100 225 400 PCB size（mm2）
1600
P. 7
LED operation circuit Non-uniform luminous intensity is created by difference of current value, caused by VF tolerance. This is often happed if LEDs are operated in parallel circuit. 25
LED①
IF（mA）
20
LED②
Therefore, 1 resistor per LED can reduce difference of current value to have uniform luminous intensity.
15 10
5 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
VF（V）
20mA 20mA
2mA 2V
LED ①
© 2018 ROHM Co.,Ltd.
20mA
LED ②
LED ①
R1
R2
1.5V LED ②
P. 8
Flow Temperature Profile According to reflow profile conditions, it may cause the breakage of die bonding for the LED of lead inserted type (Lamp LED) . (Reflow Profile E.g.) Break of Die Bonding E.g. ( Resin Decapsluated )
Temperature of solder tank/ Immersion Time
Recommend Condition
Temperature [℃]
Temperature difference of double peaks
Rohm’s Recommend condition
Bad condition
Temperature measurement point Pre-heating Condition
lead
Time [s]
Sub.
If the flow soldering condition is strict, it may cause the delamination of Ag-paste and frame due to over heat stress around the lead frame and die bonding. Make sure you use it in the following conditions: pre-heat in the temperature less than 100℃ within 60 sec.; Immerse in solder tank in the temperature less than 265℃ within 5 sec(double peaks means the time from the beginning of 1st time to the end of 2 nd time); Temperature difference of double peaks should be within 100℃. © 2018 ROHM Co.,Ltd.
P. 9
Reflow Temperature Profile According to reflow profile conditions, it may cause the breakage of die bonding. (Reflow Profile E.g.) Recommend Condition
Temperature [℃]
Rapid Heating Condition
Break of Die Bonding E.g.(X-ray)
Rohm’s Recommend condition
Rapid Cooling Condition Competitor (F corp.)
Time [s]
If the peak temperature is too high (excessive), it may cause delamination between Ag paste and circuit board due to warpage of printed wiring circuit board or expansion of resin. And if the temperature gradient of temperature rising/falling is large, it can also cause delamination, so please use it in 1～3℃/sec.
© 2018 ROHM Co.,Ltd.
P. 10
Reliability Data (Blue ,White LED) ■The Electro-optical Characteristics is recognized as Derating Data, which is not Reliability Relation. Please check Reliability Data.
Estimated Data of Residual rate of Luminous Intensity [%]
■The Reliability Data is below(Fig.1). This Data is measured at our test condition, therefore please do Reliability test yourselves at your using condition which are Assembly and Application.
Time [Hrs.]
FIG. Estimated Data of Residual rate of Luminous Intensity
Fig.1 Reliability Data
Reliability Data is shifted to Red Arrow due to using condition (High Atmosphere temperature , High Current condition) within the range of Derating. © 2018 ROHM Co.,Ltd.
P. 11
Sulfuration Sulfur corrodes Ag and it may cause a failure. Sulfuration E.g. Resin Decapsulation
The Ag pattern in the LED case is corroded and color changed into black→wire delamination Acceleration Tested Device
The Ag of frame is corroded and its color changed into black →Low luminous intensity due to low light absorption
Acceleration Tested Device
The sulfuration and corrosion of used Ag will cause the delamination of wire, furtherly result in Not Lighted and Low Luminous Intensity due to Low Light Absorption.
© 2018 ROHM Co.,Ltd.
P. 12
Mechanical Strength Comparison of the mechanical strength of LED and Transistor Diode. Comparison of main physical characteristic value of resins
LED
Transistor Diode
LED Resin
Tr・Di Resin
Specific Gravity
1.26
1.80
Scleroscope Hardness
90
81
Bending Strength[MPa]
112
151
Flexural Modulus[GPa]
3.1
15.0
We compared the mechanical strength of LED with transparent resin used and transistor diode with filer resin used, the LED is weak generally. So please do assess the mounting conditions.
© 2018 ROHM Co.,Ltd.
P. 13
Failure of Pick-up We recommend use a magnet as the countermeasure for failure of pick-up especially for small products. Magnet is used on the mounting machine for picking-up(E.g.)
Product pasted on tape due to static electricity.
No Magnet Top tape
With Magnet LED
LED
Magnet
Magnet (E.g.)
© 2018 ROHM Co.,Ltd.
For super small products, it may paste on tape due to static electricity because of the operational environment. In the case, it can solve the problem by installing a magnet on the mounting machine. P. 14
Cautions of Silicon Resin Sealed Products As for high reliability products, the reflector type is sealed by silicon resin. Therefore the sealing part is soft, it will damage the internal wire if touch it directly.
【 Mechanism of Wire Breakage due to Stress on Resin Parts】
Silicon Resin
Reflector Au Wire
Chip
Wire Deformation
Wire Breakage
Ag Frame
Solder Ag Paste
Impact or Stress applied on Silicon Resin
Mounting PCB
When it is mounting, please have the adsorption collet touching with reflector. After it is mounted, please be care to handle with the part of sealing. © 2018 ROHM Co.,Ltd.
P. 15
Not Lighted on due to Moisture Absorption 【Mechanism of Wire Bonding Breakage caused by Moisture Absorption of Product 】
Case Material (Reflector)
Au Pattern
Sealing Resin absorbing posture
Sealing Resin Expanding due to Heat Stress + Moisture Absorption
Sealing Resin
Wire Breakage
Au Wire
Chip
Substrate absorbing moisture
Solder
Mounting PCB
Delamination
Mounting Heat Stress
Stress of Vaporization
Mounting PCB
When the product is absorbing the moisture, the vaporized stream (by the heat of reflow)will go out, its stress will lift up the sealing resin from the bottom and result in breakage of wire bonding.
© 2018 ROHM Co.,Ltd.
P. 16
Storage Conditions / Packing ◇Storage Conditions（Sample) ■Molding Package type Classification
Temperature
Humidity
①Before using
5～30℃
30～70%RH
②After opening package
5～30℃
Below 70%RH
Expiration Date Within 1 year from Receiving Within 168h
Remark
Storage with waterproof package Please storing in the airtight container with our desiccant (silica gel)
■Reflector Package type（Permeability of the water high, because sealing resin touches air） Classification
Temperature
Humidity
①Before using
5～30℃
30～70%RH
②After opening package
5～30℃
Below 70%RH
Expiration Date Within 1 year from Receiving Within 72h
■Bake the product in case of below: ①The expiration date is passed. ②The color of indicator (silica gel) turned from blue to colorless or from green to pink. (Even if the product is within the expiration date.)
Remark Storage with waterproof package Please storing in the airtight container with our desiccant (silica gel)
・Baking Conditions Temperature
Time
Humidity
60±3℃
12～24h
Below 20%RH
・Bake products in reel. ・Reel and embossed tape are easy to be deformed when baking, so please try not to apply stress on it. ・Recommend bake once.
Remark
※The details, please identify specifications
◇About Packing Packing ○○○pcs are packed in one reel. ①One reel is packed in aluminum bag. ②The size of aluminum bag is ○○○(a)×○○○(b)mm. ③Aluminum bag is sealed by pressured for all directions.
ｂ
Into the aluminum pack, and sealed, prevent moisture absorption.
a © 2018 ROHM Co.,Ltd.
P. 17
RGB Chromaticity Classification of Mixed Lighting LED ◇Chromaticity Classification of Mixed Lighting
SMLVN6RGB
MSL0104RGB
SMLVN6RGB Chromaticity Classification
MSL0402RGB
When the RGB LED is white, in order to control the chromatic aberration of same set, we clarify the chromaticity when applied determined current for every product. SMLVN6RGB R 12ｍA, G 15ｍA,B 12ｍA MSL0104RGB R 8ｍA, G 14ｍA, B 18ｍA MSL0402RGB R 20ｍA, G 20ｍA, B 10ｍA
Chromaticity sorting is the value of mixed lighting when applying determined current on products. The RGB LED is different from the white LED made by blue chip + fluorescent agent, it can change the color by applying by determined currents or time setting of pulse lighting on. © 2018 ROHM Co.,Ltd.
P. 18
© 2018 ROHM Co.,Ltd.
