Datasheet
LED driver series for LCD back light
White LED driver for medium sized
and large sized LCD back light
BD9470AEFV・BD9470AFM
●General Description
BD9470AEFV and BD9470AFM are high efficiency
driver for white LED. They are designed for large sized
LCD. BD9470AEFV and BD9470AFM are built-in
DCDC converter that supply appropriate voltage for
light source.
BD9470AEFV and BD9470AFM are also built-in
protection function for abnormal state such as OVP:
over voltage protection, OCP: over current limit
protection of DCDC, SCP: short circuit protection, open
detection of LED string.
Thus they are used for conditions of large output
voltage and load conditions.
●Features
6ch LED constant current driver
LED maximum output current 250mA
Individual PWM dimming modulation allowed for
LEDs
±2% LED current accuracy (when each LED is set
to 130mA)
Built-in LED feedback voltage automatic adjustment
circuit according to LED current
Built-in start-up circuit independent of PWM light
modulation
built-in VOUT ・ FB voltage maintenance function
when PWM=Low（0%）
Built-in LED current stabilization circuit while
scanning operation is performed
Built-in VOUT discharge circuit while shutdown
Built-in LED protection (OPEN / SHORT protection)
Individual detection and individual LED OFF for
both open and short circuit
Adjustable LED short-circuit protection threshold
PWM-independent LED protection
VOUT over voltage protection (OVP) and reduced
voltage protection (SCP) circuit
Built-in failure indication function
Built-in ISET pin short-circuit protection circuit
●Key Specifications
VCC supply Voltage range:
9.0V～35.0V
LED minimum output current:
40mA
LED maximum output current:
250mA
DCDC oscillation frequency: 150KHz(RT=100Kohm)
Operation circuit current:
6mA(typ.)
Operating temperature range:
-40℃～85℃
●Applications
■ LED driver for TV, monitor and LCD back light
●Package
HSOP-M28
HTSSOP-B28
W (Typ.) x D(Typ.) x H(Max.)
18.50mm x 9.90mm x 2.41mm
9.70mm x 6.40mm x 1.00mm
Figure 1. HSOP-M28
●Typical Application Circuit
VIN
ISET
PWM
FAIL
SS
PWM1
FB
PWM2
RT
PWM3
DCDC_GND
PWM4
N
PWM5
CS
PWM6
REG58
GND
VCC
FAIL
STB
OVP
LSP
LED6
UVLO
LED5
LED1
LED4
LED2
LED_GND
LED3
Figure 2. HTSSOP-B28
STB
Figure 3. Typical Application Circuit
○Product structure：Silicon monolithic integrated circuit ○This product is not designed protection against radioactive rays
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TSZ22111・14・001
19.Oct.2013 Rev.003
BD9470AFM・BD9470AEFV
1. Specification for BD9470AEFV・BD9470AFM
●Absolute Maximum Ratings (Ta=25°C)
Parameter
Symbol
Rating
unit
VCC
-0.3~36
V
OVP Detect Voltage (DCDC Stop)
LED1~6
-0.3~40
V
STB,FAIL,UVLO,OVP
-0.3~36
V
ISET・FB・SS・
CS・N・REG58・RT pin voltage
ISET・FB・SS・CS・N・REG58・RT
-0.3~7
V
PWM1~6・LSP
Power dissipation (HSOP-M28)*1
PWM1~6・LSP
Pd
-0.3~16
5208
mW
Pd
4700
mW
LED1~6 pin voltage
STB・FAIL・UVLO・OVP pin voltage
Power dissipation (HTSSOP-B28)*2
Operating temperature range
Topr
-40～+85
℃
Storage temperature range
Tstg
-55～+150
℃
Tjmax
+150
℃
Symbol
Rating
unit
VCC
9.0 ～ 35.0
V
Maximum junction temperature
*1
Decreases -41.7mW/°C at Ta=25°C or higher (When mounting a four-layer 70.0mmx70.0mmx1.6mm board)
*2
Decreases -37.6mW/°C at Ta=25°C or higher (When mounting a four-layer 70.0mmx70.0mmx1.6mm board)
●Recommended Operating Ratings
Parameter
Supply voltage
LED1-4 pin minimum output current
ILED_MIN
40
mA*1
LED1-4 pin maximum output current
ILED_MAX
250
mA*1*2*3
LSP input voltage range
VLSP
0.3～2.5
V
fsw
100 ～ 500
kHz
PWM_MIN
30
μS
DC/DC oscillation frequency
Min. on-duty for PWM light modulation
*1
The amount of current per channel
If LED makes significant variations in its reference voltage Vf, the driver will increase power dissipation, resulting in a rise in package
*2
temperature. To avoid this problem, design the board with thorough consideration given to heat radiation measures.
*3
The LED current can be set up to 250mA
● Pin Configuration ( TOP VIEW )
ISET
PWM1
PWM2
PWM3
PWM4
PWM5
PWM6
1
2
3
4
5
6
7
28
27
26
25
24
23
22
●Outline Dimension Diagrams/Sign Diagrams
LOT No.
SS
FB
RT
DCDC_GND
N
CS
REG58
BD9470AFM
GND
FAIL
OVP
LED6
LED5
LED4
LED_GND
8
9
10
11
12
13
14
21
20
19
18
17
16
15
VCC
STB
LSP
UVLO
LED1
LED2
LED3
LOT No.
1.REG58
2.CS
3.N
4.DCDC_GND
5.RT
6.FB
7.SS
8.ISET
9.PWM1
10.PWM2
11.PWM3
12.PWM4
13.PWM5
14.PWM6
28.VCC
27.STB
26.LSP
25.UVLO
24.LED1
23.LED2
22.LED3
21.LED_GND
20.LED4
19.LED5
18.LED6
17.OVP
16.FAIL
15.GND
BD9470AEFV
Figure 4. Pin Configuration（TOP VIEW）
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Figure 5. Outline Dimension Diagrams/Sign Diagrams
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19.Oct.2013 Rev.003
BD9470AFM・BD9470AEFV
Contents
1. Specification for BD9470AEFV・BD9470AFM
P2～P9
P2
P2
P2
P2
P4,P5
P6
P6
P7
P8
P8,P9
●Absolute Maximum Ratings
●Recommended Operating Ratings
●Pin Configuration
●Outline Dimension Diagrams/Sign Diagrams
●Electrical Characteristics
●Pin Numbers, Names, and Functions
●External Component Recommended Range
●Internal Equivalent Circuit Diagrams
●Block Diagram
●Characteristic date
2. Understanding BD9470AEFV・BD9470AFM
P10～P12
P10～P12
●Pin Functions
3. Application of BD9470AEFV・BD9470AFM
P13～P32
3.1 BD9470AEFV, BD9470AFM examination for application
P13～P27
P13,P14
P15
P16
P17,P18
P19,P20
P21,P22
P23
P23
P24
P25
P26
P27
●Start-up and SS capacity setting explanation
●The setting of REG58 capacity and shutdown procedure
●VCC series resistance setting procedure
●The necessity for holding output voltage and FB voltage while PWM=Low
●Explanation of VOUT（OVP） voltage holding function when PWM=Low
●FB current Source mode・Sink/Source mode
●LED Current setting
●DC/DC converter drive frequency setting
●UVLO setting procedure
●OVP/SCP setting method
●LSP setting procedure
●Timer latch function
3.2 Selection of DCDC components
●OCP setting procedure/DCDC component current tolerance selection procedure
●Selection of Inductor L
●Selection of switching MOSFET transistors
●Selection of rectifier diodes
P28～P30
P28,P29
P30
P30
P30
3.3 Timing chart
P31
3.4 List of protection function
P32
4. Caution on use
P33
5. Ordering Information
P34
6. Revision history
P35
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BD9470AFM・BD9470AEFV
●Electrical Characteristics (unless otherwise specified, Ta = 25°C, VCC=24V )
Parameter
Symbol
Specification
Min
Typ
Max
unit
Condition
【Whole Device】
Operation Circuit
Icc
－
5.5
8.5
mA
STB=3V, PWM1-6=3.3V
Standby current
IST
－
40
80
μA
STB=0V
Operating voltage (VCC）
VUVLO_VCC
6.5
7.5
8.5
V
VCC=SWEEP UP
Hysteresis voltage （VCC）
VUHYS_VCC
150
300
600
mV
VCC=SWEEP DOWN
UVLO release voltage
VUVLO_U
2.88
3.00
3.12
V
VUVLO=SWEEP UP
UVLO hysteresis voltage
VUHYS_U
250
300
350
mV
VUVLO=SWEEP DOWN
UVLO pin leakage current
UVLO_LK
-2
0
2
μA
VUVLO=4V
VLED
0.36
0.40
0.44
V
VLED
0.428
0.450
0.472
V
FCT
142.5
150
157. 5
KHz
RT=100kohm
NMAX_DUTY
90
95
99
%
RT=100kohm
RT short protection range
RT_DET
-0.3
-
VRT×90%
V
RT=SWEEP DOWN
On resistance on N pin source
side
RONSO
1.5
3
6
Ω
On resistance on N pin sink side
RONSI
1.5
3
6
Ω
VRT
1
1.5
2
V
RT=100kohm
ISSSO
-2.6
-2.0
-1.4
μA
VSS=2V
VSS_END
3.52
3.70
3.88
V
SS=SWEEP UP
FB source current
IFBSO
-115
-100
-85
μA
VLED=0V, VFB=1.0V
FB sink current
IFBSI
70
100
130
μA
VLED=5.0V(ALL_CH),
VFB=1.0V,VSS=4V
FB_SO_SS
4.9
-
-
V
SS=SWEEP UP
FB_SOSI_SS
3.9
-
4.4
V
SS=SWEEP DOWN
Over current detect voltage
VCS
372
400
428
mV
CS=SWEEP UP
CS source current
ICS
15
30
60
μA
VCS=0V
VOVP
2.90
3.00
3.10
V
VOVP SWEEP UP
V
VOVP SWEEP DOWN
【UVLO Block】
【DC/DC Block】
Error amp. Reference voltage
(Min)
Error
amp.
basic
voltage
(ILED=130mA)
Oscillation frequency
Max. duty cycle of output N
RT pin voltage
SS pin source current
Soft start completion voltage
FB source mode
SS pin input voltage range
FB sink/source mode
SS pin input voltage range
LEDx Terminal
40mA
LEDx Terminal
130mA
ILEDx =
ILEDx =
【DC/DC protection Block】
OVP Detect
Stop)
Voltage
(DCDC
OVP protection timer release
Short protection detect voltage
OVP pin leakage current
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VOVP_CAN
VOVP-0.14 VOVP-0.1 VOVP-0.04
VSCP
0.05
0.1
0.15
V
VOVP SWEEP DOWN
OVP_LK
-2
0
2
μA
VOVP=4V
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BD9470AFM・BD9470AEFV
●Electrical Characteristics (unless otherwise specified, Ta = 25°C, VCC=24V)
Parameter
Symbol
Specification
Min
Typ
Max
unit
Condition
【LED Driver Block】
LEDｘ pin current accuracy1
⊿ILED1
-2
-
2
%
ILED=130mA
LEDｘ pin current accuracy2
⊿ILED2
-2.5
-
2.5
%
ILED=150mA
LEDｘ pin leakage current
⊿ILED3
-3.5
3.5
%
ILED=250mA
ISET pin voltage
ILLED
-0.8
-
0.8
uA
STB=H,
LEDx=40V
LEDｘ pin current accuracy1
VISET
1.3
1.5
1.7
V
RISET=30kΩ
ISET_DET
-0.3
-
VISET×90%
V
ISET=SWEEP DOWN
PWMx=L,
【LED protection Block】
ISET short circuit protection range
VLSP
8.5
9
9.5
V
LEDx=SWEEPUP,
LSP=OPEN
LSP pin resistive divider(Higher
R)
RULSP
1860
3100
5580
kΩ
LSP=0V
LSP pin resistive divider(Lower R)
RDLSP
540
900
1620
kΩ
LSP=4V
LEDｘ OPEN detect voltage
VOPEN
0.15
0.20
0.25
V
LEDx=SWEEP DOWN
REG58 output voltage 1
REG58_1
5.742
5.8
5.858
V
IO=0mA
REG58 output voltage 2
REG58_2
5.713
5.8
5.887
V
IO=-15mA
REG58 max output current
| IREG58 |
15
－
-
mA
REG58_UVLOdetect voltage
REG58_TH
2.1
2.4
2.7
V
REG58_UVLO Hysteresis
REG58_HYS
100
200
400
mV
REG58 Discharge current
REG58_DIS
3.0
5.0
7.0
uA
STB=ON->OFF REG58=4V
STB pin HIGH voltage
STBH
2
-
35
V
STB=SWEEP UP
STB pin LOW voltage
STBL
-0.3
-
0.8
V
STB=SWEEP DOWN
STB pin Pull Down resistance
RSTB
600
1000
1800
kΩ
VSTB=3.0V
PWMｘ pin HIGH voltage
PWM_H
1.5
-
15
V
PWMｘ=SWEEP UP
PWMｘ pin LOW voltage
PWM_L
-0.3
-
0.8
V
PWMｘ=SWEEP DOWN
PWMｘ pin Pull Down resistance
RPWM
1200
2000
3600
kΩ
PWMｘ=3.0V
FAIL Pin Ron
RFAIL
250
500
1000
Ω
VFAIL=1.0V
FAIL Pin Leakage current
ILFAIL
-2
0
2
μA
VFAIL=5V
LEDｘSHORT protection voltage
【REG58 BLock】
STB=ON
REG58=SWEEP DOWN
STB=ON->OFF
REG58=SWEEP DOWN
【STB Block】
【PWM Block】
【FAIL Block（OPEN
DRAIN）】
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TSZ02201-0F10C1002000-1-2
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BD9470AFM・BD9470AEFV
●Pin Numbers/Names/Functions
Pin No.
Pin Name
HSOP-M28 HTSSOP-B28
Symbol
Function
1
8
ISET
2
9
PWM1
PWM light modulation signal input pin for LED1
3
10
PWM2
PWM light modulation signal input pin for LED2
4
11
PWM3
PWM light modulation signal input pin for LED3
5
12
PWM4
PWM light modulation signal input pin for LED4
6
13
PWM5
PWM light modulation signal input pin for LED5
7
14
PWM6
PWM light modulation signal input pin for LED6
8
15
GND
Ground pin for analog block
9
16
FAIL
Error detection output pin
10
17
OVP
Overvoltage protection detection pin
11
18
LED6
LED output 6
12
19
LED5
LED output 5
13
20
LED4
LED output 4
14
21
LED_GND
15
22
LED3
LED output 3
16
23
LED2
LED output 2
17
24
LED1
LED output 1
18
25
UVLO
Detection pin for Under voltage Lockout prevention
19
26
LSP
LED short-circuit protection voltage setting pin
20
27
STB
Enable pin
21
28
VCC
Power supply pin
22
1
REG58
23
2
CS
24
3
N
25
4
DCDC_GND
26
5
RT
DCDC Drive frequency setting connection pin
27
6
FB
Error Amp output pin
28
7
SS
Slow start/
LED protection masking time setting pin
LED current setting resistor connection pin
Ground pin for LED
5.8V regulator output pin / Shutdown timer pin
DC/DC output current detection pin
OCP detection pin
DC/DC switching output pin
DC/DC GND pin
●External Component Recommended Range
Parameter
Symbol
Specification
VCC pin connecting capacity
CVCC
0.1 ～ 100
μF
VCC pin connecting resistance
RVCC
0 ～ *1
kΩ
REG58 pin connecting capacity
C_REG
1.0～470
μF
CSS
0.001～1.0
μF
RRT
30～150
kΩ
RISET
12.16～75
kΩ
Soft start setting capacity
RT pin connection resistance range
ISET pin connecting resistance range
unit
The operating conditions listed above are constants for the IC alone. To make constant setting with practical set devices, utmost attention should be paid.
*1 Please refer to 【3.2 function explanatiob and selection of external components for thes election of VCC
series resistance.
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BD9470AFM・BD9470AEFV
●Internal Equivalent Circuit Diagrams
REG58 / N / CS / DCDC_GND
SS
FB
SS
REG58
N
FB
DCDC_GND
CS
OVP
ISET
RT
2k
OVP
4k
100k
STB
FAIL
STB
1M
5V
RT
ISET
5V
UVLO
FAIL
1M
500
1M
LED1-6/LED_GND
UVLO
5V
PWM
LSP
LED1-6
4V
PWM1-6
100k
3.1M
LSP
100k
5V
2M
5V
900k
LED_GND
Figure 6. Internal Equivalent Circuit Diagrams
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BD9470AFM・BD9470AEFV
● Block Diagram
VIN
C IN
+
CREG
COUT
REG58
OS DET
VCC
VCC
C VCC
UVLO
UVLO
(VCC)
STB
TSD
UVLO
SCP
OVP
OVP
Timer
LOGIC
VREG
FAIL
PWM COMP
+
+
+
RT
OSC
Driver
Control
Logic
Current
Sence
REG58
N
CS
SS
SS
Css
AGND
Rpc
-
Cpc
+
Use at
At sink source mode
SS FB
Clamp
FB
ERR AMP
SS_END
DCDC_GND
LED1
LED2
LED3
LED4
LED5
LED6
Current driver
PWM1
PWM2
PWM3
PWM4
PWM5
PWM6
3V
1.5V
LEDGND
ISET
ISET
SS_END
4V
Open-Short
Detect
0.9V
LSP
OSDET
Figure 7. Block Diagram
●Characteristic date(reference date)
10
7.0
9
6.5
REG58[V]
ICC[mA]
8
7
6
5
6.0
5.5
4
5.0
3
9
14
19
24
VCC[V]
29
34
Figure 8. ICC[mA] vs VCC[V]
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9
14
19
24
VCC[V]
29
34
Figure 9. REG58[V] vs VCC[V]
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BD9470AFM・BD9470AEFV
140
160
138
120
136
80
40
132
IFB[uA]
ILED[mA]
134
130
128
0
-40
126
-80
124
-120
122
80
LEDx[V]
Figure 11. IFB[uA] vs LEDx[V]
( @ILED=130mA)
Figure 10. ILED[mA] vs Temp[℃]
1000
1000
FCT [ kHz ]
ILEDx[mA]
1.0
60
0.8
20
40
Temp[℃]
0.6
0
0.4
-20
0.0
-40
0.2
-160
120
100
10
100
10
10
100
RISET[kohm]
100
RRT[kohm]
1000
Figure 13. FCT [kHz] vs RRT[kohm]
Figure 12. ILEDx[mA] vs RISET[kohm]
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TSZ02201-0F10C1002000-1-2
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BD9470AFM・BD9470AEFV
2. Understanding BD9470AEFV・BD9470AFM
●Pin Functions
○ISET （HTSSOP-B28:8PIN/HSOP-M28：1PIN）
The ISET pin is a resister value of output current setting. The output current ILED vary in inverse proportion to resister
value. The relation of the output current ILED and ISET pin connecting resistor RISET are as bellow.
RISET =
3000
[kΩ]
I LED [mA]
However, current setting range is from 40mA to 150mA.
And the setting of ISET resistor is bellow at using 150mA to 250mA.
RISET = 2653 × ( I LED [mA] ) −0.9753
[kΩ]
ILED(mA)
150
160
170
180
190
200
210
220
230
240
250
RSET(kohm)
20.00
18.80
17.72
16.76
15.90
15.12
14.42
13.78
13.19
12.66
12.16
For a setting example, please refer to ‘3.1 application explanation / LED current setting’.
When the RISET is shorted and the ISET pin is grand shorted, the LED current is OFF and the FAIL=OPEN(abnormal
signal) to prevent flowing a large current to LED pin when it becomes less than VISET×0.90V(typ).
When the ISET pin back to normal state the LED current return to former system, too and the FAIL=GND(normal signal).
It prepare automatically to suitable LED feedback voltage that can output LED current set by ISET pin.
In short LED feedback voltage is dropped when the LED current is small and the IC heating is held automatically.
In case of a large current is needed, raise the LED pin feedback voltage. And it adjust automatically to LED pin voltage that
can be flow large LED current.
The calculation is as below.
VLED = 3.462 × I LED [ A] [V ]
The LED feedback voltage (VLED) is clamped to 0.4V(typ.) when the LED current (ILED) is less than 115.6mA.
○PWM1-6 （HTSSOP-B28:9,10,11,12,13,14PIN / HSOP-M28：2,3,4,5,6,7PIN）
The ON/OFF pin for LED driver. Light can be modulated by changing the duty cycle through the direct input of a PWM
light modulation signal in each PWM pin.
The high and low voltage levels of PWM_x pins are as listed in the table below.
State
PWMxvoltage
LED ON state
PWMx=1.5V~15.0V
PWMx=‐0.3V～0.8V
LED OFF state
The sequence of STB/PWM for start-up, please input PWM signal before STB or the same timing STB=PWM=ON.
○GND （HTSSOP-B28:15PIN /
IC internal analog GND pin.
HSOP-M28：8PIN）
○FAIL （HTSSOP-B28:16PIN / HSOP-M28：9PIN）
FAIL signal output pin （OPEN DRAIN）.Internal NMOS will become OPEN while abnormal is detected.
State
FAILoutput
Normal
GND
Abnormal（After Timer Latch）
OPEN Level
○OVP （HTSSOP-B28:17PIN / HSOP-M28：10PIN）
The OVP pin is an input pin for overvoltage protection and short circuit protection of DC/DC output voltage. If over voltage
is detected, the OVP pin will stop the DC/DC converter conducting step-up operation. If Vout was increased by abnormality,
timer is set while OVP＞2.9V(typ.).when it comes to OVP＞3.0V, timer will ON at the same time and to stop DCDC.
Although Counter will be stopped when OVP＜2.9V during counting time, in the state of OVP>2.9V, when internal counter
18
completed 2 count （262152 count）, the system will be latched.
When the short circuit protection (SCP) function is activated, the DC/DC converter will stop operation, and then the timer
16
will start counting, after 2 count（65536 count）, DCDC and LED driver will stop and latch.
The OVP pin is of the high impedance type and involves no pull-down resistor, resulting in unstable potential in the
open-circuit state. To avoid this problem, be sure to make input voltage setting with the use of a resistive divider or
otherwise. OVP pin will be feedback pin when PWM=L. Also, this pin will hold OVP voltage at that time when switch PWM
= H to L.
For setting example, refer to information in“3.4 Selection of External Components-OVP/SCP setting procedure
OVP Voltage keep internal IC with PWM=Low timing, and VOUT voltage can hold by using copied OVP voltage while
PWM=Low.（The OVP keep voltage range is 0~3V, 30steps）.For setting example, refer to information in “3.2 Selection of
External Components”, “Explanation of VOUT（OVP） voltage holding function when PWM=Low”
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○LED1-6 （HTSSOP-B28:18,19,20,22,23,24PIN / HSOP-M28：11,12,13,15,16,17PIN）
LED constant current output pins. Current value setting can be made by connecting a resistor to the ISET pin.
For the current value setting procedure, refer to the description of “ISET pin”.
If any of the LED pins is put in an abnormality state (short circuit mode, open circuit mode, ground short mode), the
relevant protection function will be activated.
・LED pin short circuit protection function ( LSP)
When any LED is in short state (more than LED=9.0V(typ)) the LED SHORT is detected.
16
After abnormal detection, the timer count starts. The LED that is abnormal detection after 2 count is stopped and other
LED driver operates normally.
・LED pin open circuit protection function (LOP)
If any of the LED pins becomes open-circuited (0.2V (Typ.) or less), LED_OPEN will be detected. When this error is
detected, the timer will start counting, When it completes counting the preset period of time, only LED driver that detected
the error will stop operation and other LED driver will conduct normal operation.
・LED GND_SHORT protection function
When any LED pin is GND shorted the LED pin becomes less than 0.20V and the pin is latched because of LED_OPEN
detection. After that, the LED pin is pull upped by inner supply but it continues less than 0.2V state in grand shorted. After
7
detecting timer of open state, if the grand shorted (open) state continues 2 counts all systems are latched.
To prevent the miss detection there is 4 count interval of mask before starting the timer count.
If PWM=H time is
PWM=H time < 4count・・・Not detect protection because it is in interval time
PWM=H time > 4count・・・Detect protection because it is out of interval time
Please verify enough to operate narrow PWM.
9V
LEDx
Interval of mask
Timer count
CLK
1 2 3 4 1 2
216
FAIL
Figure 14. Timing chart of timer count
○LED_GND （HTSSOP-B28:21PIN / HSOP-M28：14PIN）
The LED_GND pin is a power ground pin used for the LED driver block.
○UVLO （HTSSOP-B28:25PIN / HSOP-M28：18PIN）
This pin is used to for step-up DC/DC converter. When UVLO pin voltage reaches 3.0V (Typ.) or more, IC will initiate
step-up operation. If it reaches 2.7V (Typ.) or less, the IC will stop the step-up operation.
The UVLO pin is of the high impedance type and involves no pull-down resistor, resulting in unstable potential in the
open-circuited state. To avoid this problem, be sure to make input voltage setting with the use of a resistive divider or
otherwise.
For calculation examples, refer to information in ’3.1 application explanation/UVLO setting procedure’
○LSP （HTSSOP-B28:26PIN / HSOP-M28：19PIN）
The setting pin for detection voltage of LED short circuit protection. The LED short circuit detection voltage is set to 9V
(Typ.) with the LSP pin being in the open-circuited state. However, making a change to the LSP pin input voltage will allow
the threshold for LED short circuit protection to be changed.
The relation between the LSP pin voltage and the LED short circuit protection detection voltage is given by the following
equation.
VLSPSHORT =
VLEDSHORT
[V ]
10
Here LEDSHORT：LED detection voltage
VLSP：LSP setting voltage
LSP pin input voltage setting should be made in the range of 0.3V to 2.5V.
For setting example, refer to information in’3.1 application explanation/LSP setting procedure’
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○STB (HTSSOP-B28:27PIN / HSOP-M28：20PIN）
The pin is used to ON/OFF the IC and allowed for use to reset the IC from shutdown.
The IC state is switched between ON and OFF state according to voltages input in the STB pin. Avoid using the STB pin
between two states (0.8 to 2.0V).
Input sequence of STB/PWM for startup, please input PWM before STB or at the same timing.
While in shutdown mode, the timer keeps counting until the IC is completely shut down. For details of shutdown operation,
refer to information in’3.1 application explanation/ the setting of REG58 capacity and shutdown procedure'
○VCC （HTSSOP-B28:28PIN / HSOP-M28：21PIN）
IC power supply pin. Input range is 9~35V.
VCC pin voltage reaches 7.5V (Typ.) or more, the IC will initiate operation. If it reaches 7.2V (Typ.) or less, IC will be shut
down.
○REG58 （HTSSOP-B28:1PIN / HSOP-M28：22PIN）
The REG pin is used in the DC/DC converter driver block to output 5.8V voltage. The maximum operating current is
15mA.Using the REG pin at a current higher than 15mA can affect the N pin output pulse, causing the IC to malfunction
and leading to heat generation of the IC itself. To avoid this problem, it is recommended to make load setting to the
minimum level.
In addition, The REG58 pin is also allowed for use as discharge timer for DC/DC output capacitance.
For details, refer to information in ’3.1 application explanation/ the setting of REG58 capacity and shutdown procedure'
○CS （HTSSOP-B28:2PIN / HSOP-M28：23PIN）
The CS pin has the following two functions.
１．DC/DC current mode current feed Back function
Current flowing through the inductor is converted into voltage by the current sensing resistor RCS which connected to CS
pin and this voltage is compared with voltage set with the error amplifier to control the DC/DC output voltage.
2．Inductor current limit function (OCP pin)
The CS pin also incorporates the overcurrent protection (OCP) function. If the CS pin voltage reaches 0.4V (Typ.) or more,
switching operation will be forcedly stopped.
For detailed explanation, Please refer to information in “3.2 Selection of DC/DC Components-OCP setting procedure /
DC/DC component current tolerance selection procedure”.
○N （HTSSOP-B28:3PIN / HSOP-M28：24PIN）
The N pin is used to output power to the external NMOS gate driver for the DC/DC converter in the amplitude range of
approximately 0 to 5.8V.Frequency setting can be adjusted by a resistor connected to the RT pin. For details of frequency
setting, refer to the description of the RT pin.
○DCDC_GND （HTSSOP-B28:4PIN / HSOP-M28：25PIN）
The DCDC_GND pin is a power ground pin for the driver block of the output pin N.
○RT （HTSSOP-B28:5PIN / HSOP-M28：26PIN）
The RT pin is used to connect a DC/DC frequency setting resistor. DC/DC drive frequency is determined by connecting the
RT resistor.
・Relationship between Drive frequency and RT resistance (Ideal)
RRT =
15000
f SW [kHz ]
[kΩ]
However, drive frequency setting is limited in the range of 100 kHz to 500kHz.
For calculation, refer to information in ’3.1 application explanation/ DC/DC converter drive frequency setting’
When it reaches under VRT×0.90V(typ), DCDC operation will be stopped in order to prevent from high speed oscillation
when the RT resistance is shorted to GND. And when RT pin returns to normal state, DCDC also returns to operation.
○FB （HTSSOP-B28:6PIN / HSOP-M28：27PIN）
The FB pin is an output of DC/DC current mode error amplifier. FB pin detects the voltages of LED pins (1 to 6) and
controls inductor current so that the pin voltage of the LED located in the row with the highest Vf will come to 0.45V(130mA,
typ.). Therefore, the pin voltages of other LEDs will become higher by Vf variation.
FB Voltage keep internal IC with PWM=Low timing, and it can hold by using copied FB voltage while PWM=Low.（The FB
keep voltage range is 0~4V, 40steps）
For setting example, refer to information in ’3.1 application explanation/ the necessity for holding output voltage and FB
voltage while PWM=Low’
○SS （HTSSOP-B28:7PIN / HSOP-M28：28PIN）
Soft start time and duty for soft start setting pin. The SS pin normally sources 2.0uA (Typ.) of current.
The IC has a built-in soft start start-up circuit independent of PWM light modulation, and thereby raises FB voltage as SS
pin voltage rises independent of the duty cycle range of PWM light modulation. When the SS pin voltage reaches 3.7V
(Typ.), soft start operation will be completed to unmask the LED protection function.
For setting example, refer to information in ’3.1 application explanation/ start-up and SS capacity setting explanation’
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3. Application of BD9470AEFV・BD9470AFM
3.1 BD9470AEFV・BD9470AFM examination for application
●Start-up and SS capacity setting explanation
This section described the start-up sequence of this IC.
①
STB
2uA
5V
SS
SLOPE
FB
PWM
SS
OSC
VOUT
Q D
COMP
N
Css
DRIVER
PWM
OSC
SS=FB
Circuit
ILED
SS
SLOPE
LED
0.3～
0.519V
VOUT
ILED
③
LED_OK
OVP
KEEP
OVP
④
PWM
⑤
LED_OK
PWM=L:STOP
FB
STOP/ACT
LED_OK
N ②
LED_DRIVER
⑥
⑦
Figure 15. Timing chart of start-up
○Description of start-up sequence
①STB=PWM=ON
②System is ON.SS starts to charge.
At this time, a circuit in which SS voltage for slow start is equal to FB voltage regardless of whether the PWM pin is set to
Low or High level.
③Since the FB pin and SS pin reach the lower limit of the internal sawtooth wave, the DC/DC converter operates and
VOUT voltage rising.
Until it reachs a certain voltage even PWM=Low by vlotage maintenance function.
（For detailed OVP maintanence function, please refer to”VOUT(OVP) maintanence function section”.）
⑤Vout voltage continues rising to reach a voltage at which LED current starts flowing.
⑥When the LED current reaches the set amount of current, isolate the FB circuit from the SS circuit. With this, the start-up
operation is completed.（Fast start-up is also diasabled by VOUT maintanence function）
⑦After that, conduct normal operation following the feedback operation sequence with the LED pins.
If the SS pin voltage reaches 3.7V or more, the LED protection function will be activated to forcedly end the SS and
FBequalizing circuit.
VSS>4.9V FB=Source Mode
REG58
4.9V
V
Vss
Iss[A]
V
SS
Vss, VFB[V]
VREG58[V]
○ SS capacity setting method
4.7V＜Vss
⇒FB Output Current
=Source Only
Finished Start Up
SS=FB
Css[F]
Time
Figure 16. SS setting procedure in FB Source mode
Boot system as above described, because of start-up in the state of FB=SS, the start-up time can be imaged of the time to
reach the point from the feedback voltage FB from STB = ON.If you SS> 4.9V, FB output current mode will become Source
mode operation.
If the feedback voltage of FB is the same as VSS and the time can be calculated as below.
Tss =
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C ss [ F ] × VFB[V ]
2[ µA]
[ Sec]
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However, if SS is set too short, inductor rush current will occur during start-up.In addition, if SS time is set too long, will
result in the brighter in stages.SS capacity will veries with various factors, such as voltagestep-up ratio, DCDC driver
frequency, LED current and output output condencer, so it is recommended to test and confirm on the actual system.
（SS capacity is often set at about 0.047uF～0.47uF approximately as a reference value）
○Setting example
SS time when the start-up is complete and Css = 0.1uF, Iss = 2uA, Vss = 3.7V will be calculated as follows.
Tss =
0.1 E −6 [F] × 3.7 [ V ]
= 0.185
2 E −6 [ A ]
[Sec ]
In addition, when FB output is operated in Sink/Source mode（refer to “FB pin output current setting for detailed
explanation.）, SS voltage can be set to be in the range of 3.9V～4.4V at the SS pin voltage resistor divider.Soft-start time
will be set in that case is as follows.
A × Vss[V ]
1
ln1 −
A
B
A=
[Sec ]
R1 [ohm ] + R 2 [ohm ]
Css [F ] × R1 [ohm ] × R 2 [ohm ]
VREG58 [V ]
+ Iss[ A] ÷ Css[F ]
B =
1
[
]
R
ohm
3.9V 2kohm so that ΔV = RFB × IFB> 0.2V.
IFB(100uA typ)
FB
RFB
⊿V=RFB×IFB>0.2V
CFB
Figure 22. Voltage to FB resistor
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●Explanation of VOUT（OVP） voltage holding function when PWM=Low
VIN
VOUT
VCC
OVP
OVP_IN
OVP COPY
LED_OK
Holding OVP
Vol. BLOCK
PWM signal
-
H : DCDC ON
L : DCDC OFF
OVP
COMP
+
FB
SLOPE
+
+
-
SS
+
ICOMP
CONTROL
LOGIC
DRIVER
N
CS
DCDC_GND
LED1-6
Figure 23. Block diagram of KEEP_OVP
OVP holding function means VOUT(OVP) voltage will be copy to IC internally at a time of PWM from High to Low, voltage
will be maintained even in the period of PWM=Low.
In addition to measures of the above problems, by applying this function, the high-speed start-up can be achieved without
depending on the PWM.
Because VOUT voltage resolution is the same as FB holding function which is split by 40 from 4V,so the voltage can be
copied to IC internally in 0.1V Step.
The description of OVP holding function is divided into narrow PWM operation and start-up operation.
○Explanation of OVP holding function at start-up
PWM
②
①
⑤
OVP
OVP COPY
③
N
④
Figure 24. Timing chart 1 of KEEP_OVP
In order to launch high speed start-up without depending on the PWM DUTY, OVP holding function will behave like the
following descriptions.
①PWM=High, normal boost operation.
②OVP voltage is copied into IC when PWM is from High to Low.OVP voltage will be copied upper 1BIT at this time. For
example: if OVP=2.43V, the copied voltage is 2.5V in IC.
③The copied OVP voltage will be compared with OVP pin voltage internally, if OVP_COPY>OVP, DCDC is operated.In
other words, it is possible to achieve fast start-up by letting the voltage on the 1BIT boosted up in the interval of PWM =
Low.
④When OVP_COPY2.9V
OVP3.0V
OVP 0
2
A failure to meet this condition is referred to as discontinuous mode.
Im in = I IN [ A] −
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○Setting example
Output voltage=VOUT [V]=40V
LED total current=IOUT [A]=120mA×6ch=0.72A
DCDC input voltage=VIN [V]=24V
DCDC efficiency=η[%]=90%
mean input current IIN required for the whole system is given by the following equation
I IN [ A] =
VOUT [V ] × I OUT [ A] 40[V ] × 0.72[ A]
=
= 1.33 [ A]
V IN [V ] ×η[%]
24[V ] × 90[%]
DCDC switching frequency=fsw[Hz]=200kHz
Inductor L[H]=47μH
The Inductor ripple currentΔIL[A] is:
ΔIL =
(VOUT [V ] − VIN [V ]) × VIN [V ]
(40[V ] − 24[V ]) × 24[V ]
=
= 1.02 [ A]
L[ H ] × VOUT [V ] × f SW [ Hz ]
47 ×10 −6 [ H ] × 40[V ] × 200 ×10 3 [ Hz ]
As a result, the IL peak current Ipeak is:
Ipeak = I IN [ A] +
∆IL[ A]
1.02[ A]
[
A] = 1.33[ A] +
= 1.84 [ A]
2
2
… Result of peak current
calculation
When RCS resistance is set to 0.15ohm, the VCS peak voltage will be given by the following equation
VCS peak = Rcs × Ipeak = 0.15[Ω] × 1.84[ A] = 0.276[V ] < 0.5V
… Result of review of
RCS resistance
Consequently, the result meets the condition.
Furthermore, IOCP current at which OCP is detected is given by the following equation
I ocp =
0.4[V ]
= 2.67 [ A]
0.15[Ω]
If the current tolerance for components to be used (e.g. FETs, inductors, diodes) is smaller than 2.5A,
I peak < I OCP < Max. Current tolerance for component
= 1.84[ A] < 2.67[ A] < 3.0[ A]
… Result of review of current
tolerance for DC/DC components
As a result, since the condition above is met, the selection of components is accepted.
And, the lower limit of IL ripple current Imin is:
Im in = I IN [ A] −
∆IL[ A]
1.02[ A]
[ A] = 1.33[ A] −
= 0.82[ A] > 0
2
2
The system will not be put into discontinuous mode.
To select DC/DC components, please consider IC variations as well as individual component variations, andthen conduct
thorough verification on practical systems.
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●Selection of Inductor
The value of inductor has significant influence on the input ripple current. As shown by Equation (1), the larger the inductor
and the higher the switching frequency, the inductor ripple current ∆IL becomes
increasingly
lower.
ΔIL =
(VOUT − V IN ) × V IN
[ A] ・・・・・
(1)
L × VOUT × f SW
Efficiency as shown by Equation (2), peak input current is given as Equation
η=
VOUT × I OUT
・・・・・
(2)
VIN × I IN
ILMAX = I IN +
(3).
ΔIL
VIN
ΔIL VOUT × I OUT
ΔIL
=
+ ・・・・・
(3)
2
VIN ×η
2
IL
L
Here,
L：Reactance value [H]
VOUT：DC/DC output voltage[V]
IOUT：output current(LED total current)[A]
VIN：input voltage[V]
IIN：input current[A]
FSW：oscillation frequency[Hz]
If a current in excess of the rated current of the inductor applies to the
coil, the inductor will cause magnetic saturation, resulting in lower
efficiency.
Select an inductor with an adequate margin so that peak current will
not exceed the rated current of the inductor.
To reduce power dissipation from and increase efficiency of induct
or, select an inductor with low resistance component (DCR or AC
R).
VOUT
RCS
COUT
Figure33.
DCDC application circuit and coil current
●Selection of switching MOSFET transistors
There will be no problem for switching MOSFET transistors having absolute maximum rating higher than rated current of
the inductor L and VF higher than “COUT breakdown voltage + Rectifier diode”. However, to achieve high-speed switching,
select transistors with small gate capacity (injected charge amount).
・Rated current larger than current protection setting current is recommended
・Selecting transistors with low On resistance can obtain high efficiency.
●Selection of rectifier diodes
Select current capability higher than the rated current of the inductor L and inverse breakdown voltage higher that COUT
break-down voltage, particularly having low forward voltage VF.
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3.3 Timing Chart
VCC
7.5V
2.0V
0.8V
STB
REG58
2.4V
2.6V
GND
FAIL
( normal state )
1.5V
ISET
RT
3.7V
SS
SS=FB or LED
feed-back
FB
LED
feed-back
VOUT
1.5V
PWMｘ
0.8V
ILEDｘ
LED_OPEN
LED_SHORT
Disaable
Disaable
LED_GND_SHORT
Enable
Enable
ISET_GND_SHORT
RT_GND_SHORT
Disaable
Enable
UVLO
REG58_UVLO
VCC_UVLO
Disaable
Enable
Disaable
Enable
OVP
SCP
Disaable
Disaable
Disaable
Disaable
Disaable
Figure 34. Timing Chart
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3.4 List of Protection Functions
●List of protection detecting condition
Protection
names
Detection
pin
LED OPEN
LEDｘ
LEDSHORT
LEDｘ
Detection condition
Detection pin
PWM
condition
LEDx < 0.20V
SS
Release
condition
H
SS>3.7V
LEDx > 0.20V
H
SS>3.7V
H
SS>3.7V
LEDx > 9V
LED GND
SHORT
ISET GND
SHORT
RT GND
SHORT
Timer
2
16
count
2
16
count
LEDx < 9V
(LSP=OPEN)
(LSP=OPEN)
16
LEDｘ
LEDx < 0.20V
ISET
Under ISET×90%
RT
Under RT×90%
-
-
UVLO
UVLO
UVLO3V
REG58 UVLO
REG58
REG582.6V
VCC UVLO
VCC
VCC7.5V
LEDx > 0.20V
Canceled
ISET=GND State
Canceled
RT=GND State
OVP
OVP
OVP>3.0V
-
-
OVP0.4V
-
-
-
Latch
(Only detected
ｃｈ)
Latch
(Only
detected ｃｈ)
7
2 +2
count
Immediately
detect
Immediately
detect
Immediately
detect
Immediately
detect
Immediately
detect
18
Protection
type
Latch
Auto-restart
Auto-restart
Auto-restart
Auto-restart
Auto-restart
count
Latch
count
Latch
Immediately
detect
Pulse-by-Pulse
* To clear the latch type, STB should be set to “L” once, and then to “H”
* The count of Timer means ” 1count = 1 duty of switching frequency.
●List of protection detecting operation
Protection Functions
Operation when the hysteresis type protection is detected
DC/DC
LED OPEN
Continues operation
LEDSHORT
Continues operation
LED GNDSHORT
ISET GND SHORT
RT GND SHORT
STB
UVLO
REG58 UVLO
VCC UVLO
OVP
SCP
OCP
Stops operating after
CP counting
Instantaneously stops
operating
Instantaneously stops
operating
Instantaneously stops
operating
Instantaneously stops
operating
Instantaneously stops
operating
Instantaneously stops
operating
Stops operating after
CP counting
Stops operating after
CP counting
limits duty cycle
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LED Driver
Only detected LED stops
operating after CP counting
Only detected LED stops
operating after CP counting
Not discharged
Stops operating after CP counting
Discharge
Instantaneously stops operating
Not discharged
Normal Operation
Not discharged
Stops (and REG58(Pin A) for the resistor, or when GND>(Pin B) for the transistor (NPN), P-N junctions operate as a a
parasitic diode.
When GND>(Pin B) for the transistor (NPN), the parasitic NPN transistor operates by the N layer of other element
adjacent to the parasitic diode aforementioned.
Due to the structure of the IC, parasitic elements are inevitably formed depending on the relationships of potential. The
operation of parasitic diodes can result in interferences in circuit operation, leading to malfunctions and eventually
breakdown of the IC. Consequently, pay utmost attention not to use the IC for any applications by which the parasitic
elements are operated, such as applying a voltage lower than that of GND (P substrate) to the input pin.
Transistor (NPN)
Resistor
(Pin A)
N
P
P
P
N
B
C
(Pin B)
N
P
N
E
GND
P
P
N
N
N
P substrate
P substrate
GND
Parasitic element
GND
Parasitic element
(Pin B)
(Pin A)
B
Parasitic element
GND
C
E
ＧＮＤ
Adjacent other elements
Parasitic
Figure 35. Example of Simple Structure of
Monolithic IC
Status of this document
The Japanese version of this document is formal specification. A customer may use this translation version only for a
reference to help reading the formal version.
If there are any differences in translation version of this document formal version takes priority
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TSZ22111・15・001
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TSZ02201-0F10C1002000-1-2
19.Oct.2013 Rev.003
BD9470AFM・BD9470AEFV
●Ordering Information
B
D
9
4
7
0
Part Number
B
D
A
F
M
E2
Package
FM: HSOP-M
9
4
7
Part Number
0
A
E
Packaging and forming specification
E2: Embossed tape and reel
F
Package
EFV: HTSSOP-B
V
E2
Packaging and forming specification
E2: Embossed tape and reel
●Physical Dimension Tape and Reel Information
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TSZ22111・15・001
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TSZ02201-0F10C1002000-1-2
19.Oct.2013 Rev.003
BD9470AFM・BD9470AEFV
6. Revision history
Date
Revision
26.Oct.2012
001
09.Jan.2013
19.Oct.2013
Changes
New Release
002
P6 / Verified minimum ISET resistor
002
P10 / Verified ISET terminal instruction
002
P23 / Verified LED Current setting
003
P2 / Change Pin Configuration
003
P1 / Delete PbFree, RoHS
003
ADD NOTICE
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19.Oct.2013 Rev.003
Datasheet
Notice
Precaution on using ROHM Products
1.
Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
(Note 1)
, transport
intend to use our Products in devices requiring extremely high reliability (such as medical equipment
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN
USA
EU
CHINA
CLASSⅢ
CLASSⅡb
CLASSⅢ
CLASSⅢ
CLASSⅣ
CLASSⅢ
2.
ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3.
Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4.
The Products are not subject to radiation-proof design.
5.
Please verify and confirm characteristics of the final or mounted products in using the Products.
6.
In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7.
De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual
ambient temperature.
8.
Confirm that operation temperature is within the specified range described in the product specification.
9.
ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1.
When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2.
In principle, the reflow soldering method must be used; if flow soldering method is preferred, please consult with the
ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice - GE
© 2014 ROHM Co., Ltd. All rights reserved.
Rev.002
Datasheet
Precautions Regarding Application Examples and External Circuits
1.
If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2.
You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1.
Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2.
Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3.
Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4.
Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
QR code printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act,
please consult with ROHM representative in case of export.
Precaution Regarding Intellectual Property Rights
1.
All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data. ROHM shall not be in any way responsible or liable
for infringement of any intellectual property rights or other damages arising from use of such information or data.:
2.
No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the information contained in this document.
Other Precaution
1.
This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2.
The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3.
In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4.
The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
Notice - GE
© 2014 ROHM Co., Ltd. All rights reserved.
Rev.002
Datasheet
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3.
The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or
concerning such information.
Notice – WE
© 2014 ROHM Co., Ltd. All rights reserved.
Rev.001
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