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Hi-performance Regulator IC Series for PCs
Main Power Supply IC
for Note PC (Linear Regulator Integrated)
BD9524MUV
Description
BD9524MUV is a switching regulator controller with high output current which can achieve lo w output voltage (2.0V5.5V)
from a wide input voltage range (7V~25V). High efficiency for the switching regulator can be realized by utilizing an external
N-MOSFET power transistor. A new technology called H3RegTM is a Rohm proprietary control method to realize ultra high
transient response against load change. SLLM (Simple Light Load Mode) technology is also integrated to improve efficiency
in light load mode, providing high efficiency over a wide load range. For protection and ease of use, the soft start function,
variable frequency function, short circuit protection function with timer latch, over voltage protection with timer latch, and
Power good function are all built in. This switching regulator is specially designed for Main Power Supply.
Features
1) 2ch H3RegTM Switching Regulator Controller
2) Adjustable Simple Light Load Mode (SLLM), Quiet Light Load Mode (QLLM) and Forced continuous Mode
3) Thermal Shut Down (TSD), Under Voltage Lock Out (UVLO), Over Current Protection (OCP),
Over Voltage Protection (OVP), Short circuit protection with timer-latch (SCP)
4) Soft start function to minimize rush current during startup
5) Switching Frequency Variable (f=200KHz500KHz)
6) Power good circuit
7) 2ch Linear regulator
8) VQFN032V5050 package
Applications
Laptop PC, Desktop PC, LCD-T V, Digital Compon ents
Maximum Absolute Ratings (Ta=25)
*1 Do not however exceed Pd.
*2 Instantaneous surge voltage, back electromotive force and voltage under less than 10% duty cycle.
*3 Reduced by 3.0mW for each increase in Ta of 1 over 25 (when don’t mounted on a heat radiation board )
*4 Reduced by 7.0mW for increase in Ta of 1 over 25. (when mounted on a board 70.0mm×70mm×1.6mm Glass-epoxy PCB
which has 1 layer. (Copper foil area : 0mm2))
*5 Reduced by 16.5mW for increase in Ta of 1 over 25. (when mounted on a board 70.0mm×70mm×1.6mm Glass-epoxy PCB
which has 4 layer s. (1st and 4th copper foil area : 20.2mm 2, 2 nd and 3rd copper foil area : 5505mm2))
*6 Reduced by 36.5mW for increase in Ta of 1 over 25. (when mounted on a board 70.0mm×70mm×1.6mm Glass-epoxy PCB
which has 4 layers. (All copper foil area : 5505mm2))
Parameter Symbol Limits Unit
Terminal voltage
VIN, CTL 30 *1*2 V
EXTVCC, PGOOD1, PGOOD2FB1, FB2, Is+1, Is+2, MCTL 7*1*2 V
FS1, FS2, REF1, REF2, SS1, SS2, LG1, LG2 REG1+0.3*1*2 V
BOOT1, BOOT2 35*1*2 V
BOOT1-SW1, BOOT2-SW2, HG1-SW1, HG2-SW2 7*1*2 V
HG1 BOOT1+0.3*1*2 V
HG2 BOOT2+0.3 *1*2 V
EN1, EN2 6 *1*2 V
DGND, PGND1, PGND2 AGND±0.3 *1*2 V
Power dissipation 1 Pd1 0.38 *3 W
Power dissipation 2 Pd2 0.88 *4 W
Power dissipation 3 Pd3 2.06 *5 W
Power dissipation 4 Pd4 4.56 *6 W
Operating temperature range Topr -10 ~ +100
Storage temperature range Tstg -55 ~ +150
Junction Temperature Tjmax +150
No.10030ECT06
BD9524MUV
Technical Note
2/20
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Operating Conditions (Ta=25)
Parameter Symbol MIN. MAX. Unit
Terminal voltage
VIN 7 25 V
EXTVCC 4.5 5.5 V
CTL -0.3 25 V
EN1, EN2 -0.3 5.5 V
BOOT1, BOOT2 4.5 30 V
BOOT1-SW1, BOOT2-SW2, HG1-SW1, HG2-SW2 -0.3 5.5 V
PGOOD1, PGOOD2 -0.3 5.5 V
FS1, FS2 0.09 1.25 V
REF1, REF2 1 2.75 V
Is+1, Is+ 2, FB1, FB2 1.9 5.6 V
MCTL -0.3 REG1+0.3 V
*This product should not be used in a radioactive environment.
Electrical characteristics
(unless otherwise noted, Ta=25 VIN=12V, CTL=5V, EN1=EN2=5V, REF1=2.5V, REF2=1.65V, FS1=FS2=0.582V)
Parameter Symbol
Standard Value Unit Conditions
MIN. TYP. MAX.
VIN standby current ISTB 70 150 250 μA CTL=5V, EN1=EN2=0V
VIN bias current IIN 0 45 130 μA EXTVCC=5V
Shut down mode current ISHD -10 0 10 μA CTL=0V
CTL Lo w voltage VCTLL -0.3 - 0.8 V
CTL High voltage VCTLH 2.3 - 25 V
CTL bias current ICTL - 1 3 μA VCTL=5V
EN Low voltage VENL -0.3 - 0.8 V
EN High voltage VENH 2.3 - 5.5 V
EN bias current IEN - 1 3 μA VEN=3V
[5V linear regulator]
REG1 output voltage VREG1 4.90 5.00 5.10 V IREG1=1mA
Maximum current IREG1 200 - - mA IREG2=0mA
Line Regulation REG1I - 90 180 mV VIN=7.5 to 25V
Load Regulation REG1L - 30 50 mV IREG1=0 to 30mA
[3.3V linear regulator]
REG2 output voltage VREG2 3.27 3.30 3.33 V IREG2=1mA
Maximum current IREG2 100 - - mA
Line regulation REG2I - - 20 mV VIN=7.5 to 25V
Load regulation REG2L - - 30 mV IREG2=0 to 100mA
[5V switch block]
EXTVCC input threshold voltage VCC_UVLO 4.2 4.4 4.6 V EXTVCC: Sweep up
EXTVCC input delay time TVCC 2 4 8 ms
Switch Resistance RVCC 1.0 2.0
[Under voltage lock out block for DC/DC]
REG1 threshold voltage REG1_UVLO 4.0 4.2 4.4 V REG1: Sweep up
REG2 threshold voltage REG2_UVLO 2.45 2.65 2.85 V REG2: Sweep up
Hysteresis voltage dV_UVLO 50 100 200 mV REG1, REG2: Sweep down
[Error amplifier block]
Feedback voltage 1 VFB1 REF1×2
-25m REF1×2REF1×2
+25m V
FB1 bias current IFB1 20 45 90 μA FB1=5V
Output discharge resistance 1 RDISOUT1 0.5 1 3 k
Feedback voltage 2 VFB2 REF2×2
-25m REF2×2REF2×2
+25m V
FB2 bias current IFB2 10 30 60 μA FB2=3.3V
Output discharge resistance 2 RDISOUT2 0.5 1 3 k
REF1, REF2 bias current IREF1, IREF2 -10 - 10 μA
BD9524MUV
Technical Note
3/20
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Electrical characteristics - Continued
(unless otherwise noted, Ta=25 VIN=12V, CTL=5V, EN1=EN2=5V, REF1=2.5V, REF2=1.65V, FS1=FS2=0.582V)
Parameter Symbol
Standard Value Unit Conditions
MIN. TYP. MAX.
[H3RegTM block]
On T ime 1 TON1 0.810 0.960 1.110 μs REF=2.5V
On T ime 2 TON2 0.520 0.670 0.820 μs REF=1.65V
Maximum On Time TONMAX 3.5 7 14 μs
Minimum Off Time TOFFMIN - 0.2 0.4 μs
FS1, FS2 bias current IFS -10 0 10 μA
[FET driver block]
HG higher side ON resistor HGHON - 3.0 6.0
HG lower side ON resistor HGLON - 2.0 4.0
LG higher side ON resistor LGHON - 2.0 4.0
LG lower side ON resistor LGLON - 0.5 1.0
[Over Voltage Protection block]
Latch T y pe OVP Threshold voltage VLOVP REF×2
×1.15 REF×2
×1.175 REF×2
×1.20 V
Latch Type OVP delay time TLOVP 50 150 300 μs
[Short circuit protection block]
SCP Threshold voltage VSCP REF×2×
0.66 REF×2
×0.7 REF×2
×0.74 V
Delay time TSCP 0.5 1 2 ms
[Current limit protection block]
Maximum offset voltage dVSMAX 50 65 80 mV
Is+1 bias current IISP1 - 2.5 10 μA
Is+2 bias current IISP2 - 2.5 10 μA
[Power good block]
Power good low threshold VPGTHL REF×2
×0.87 REF×2
×0.90 REF×2
×0.93 V
Power good high threshold VPGTHH REF×2
×1.07 REF×2
×1.10 REF×2
×1.13 V
Power good low voltage VPGL - 0.1 0.2 V IPGOOD=1mA
Power good leakage current ILEAKPG -2 0 2 μA VPGOOD=5V
[Soft Start block]
Charge current ISS 1.8 2.5 3.2 μA
Standby voltage VSS_STB - - 50 mV
[SLLM mode control block]
MCTL terminal voltage 1 VCONT -0.3 - 0.3 V Continuous mode
MCTL terminal voltage 2 VQLLM 1.5 - 3.0 V QL2M mode
(Maximum LG off time : 50μs)
MCTL terminal voltage 3 VSLLM 4.5 - REG1+0.3 V SL2M mode
(Maximum LG off time : )
MCTL float level VMCTL 1.5 - 3.0 V
Output condition table Input Output
CTL EN1 EN2 REG1(5V) REG2(3.3V) DC/DC1 DC/DC2
Low Low Low OFF OFF OFF OFF
Low Low High OFF OFF OFF OFF
Low High Low OFF OFF OFF OFF
Low High High OFF OFF OFF OFF
High Low Low ON ON OFF OFF
High Low High ON ON OFF ON
High High Low ON ON ON OFF
High High High ON ON ON ON
BD9524MUV
Technical Note
4/20
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Block Diagram, Application circuit
*Apply the supply voltage EXTVCC pin after REG1 pin is operated.
REG1
Overlap
Protection
Circuit
Overlap
Protection
Circuit
SL2MTM
Block SL2MTM
Block
H3RegTM
Controller
Block
H3RegTM
Controller
Block
5V
Reg 3.3V
Reg
Reference
Block
Thermal
Protection
CL2
SCP2 CL1
SCP1
REG1 REG1
FS2 FS1
REG1
VIN
Vo2
A
djustable
REG1
VIN
Vo1
A
djustable
VIN
REG2
REG2
REG2
REG2
Timer
Timer
SCP2
SCP1
Short Circuit Protect
Short Circuit Protect
Over Voltage
Protect
Over Volt ag e
Protect
EN2 EN1
TSD
UVLO
CL2
CL1
FB2
FB1
VIN
BOOT2
HG2
SW2
LG2
PGND2
BOOT1
HG1
SW1
LG1
PGND1
AGND
DGND
FS1
FB1
REF1
PGOOD1
Is+1
EN1
EN2
Is+2
PGOOD2
REF2
FB2
1
2
3
4
5
VIN
CTL
EXTVCC
REG1
REG2
VIN
7
25V
REG1
5V
3.3V
30 18 27 29 28
21
16
20
17
15
31 32 22 23 24 26 25
13
7
14
8
10
9
REF2
FB2
REF1
FB1
REG2
MCTL2 MCTL1
SS2
SS1
Power Good Block
Power Good Block
FS2
11
12
MCTL MCTL2
MCTL1
SL2M Mode Control
6
SS2 SS2
Soft Start Block
19
SS1 SS1
Sof t St art Block
VIN
Current Limit
Protect
Current Limit
Protect
BD9524MUV
Technical Note
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Pin Configuration
Pin Function Table
PIN No. PIN name PIN Function
1 SW2 Highside FET source pin 2
2 HG2 Highside FET gate drive pin 2
3 BOOT2 HG Driver power supply pin 2
4 EN2 Vo2 ON/OFF pin (High=ON, Low=OFF)
5 PGOOD2 Vo2 Power Good Open Drain Output pin
6 SS2 Vo2 soft start pin
7 DGND Ground
8 REF2 Vo2 output voltage setting pin
9 Is+2 Current sense pin +2
10 FB2 Vo2 output voltage sense pin, current sense pin -2
11 FS2 Input pin for setting Vo2 frequency
12 MCTL Mode shift pin (Low=continuous, Middle=QLLM, High=SLLM)
13 AGND Input pin Ground
14 FS1 Input pin for setting Vo1 frequency
15 FB1 Vo2 output voltage sense pin, current sense pin -1
16 Is+1 Current sense pin +1
17 REF1 Vo1 output voltage setting pin
18 CTL Linear regulator ON/OFF pin (High=ON, Low=OFF)
19 SS1 Vo1 soft start pin
20 PGOOD1 Vo1 Power Good Open Drain Output pin
21 EN1 Vo1 ON/OFF pin (High=ON, Low=OFF)
22 BOOT1 HG Driver power supply pin 1
23 HG1 Highside FET gate drive pin 1
24 SW1 Highside FET source pin 1
25 PGND1 Lowside FET source pin 1
26 LG1 Lowside FET gate drive pin 1
27 EXTVCC Outside power supply input pin
28 REG2 3.3V lin ear regulator output pin
29 REG1 5V lin ear regulator output pin
30 VIN Power supply input pin
31 LG2 Lowside FET gate drive pin 2
32 PGND2 Lowside FET source pin 2
Reverse FIN Exposed Pad, Connect to GND
31 2 4 5678
9
10
11
12
13
14
15
16
24 23 22 21 20 19 18 17
32
31
30
29
28
27
26
25
PGND1
LG1
SW2
HG2
BOOT2
EN2
PGOOD2
SS2
DGND
REF2
SW1
HG1
BOOT1
EN1
PGOOD1
SS1
CTL
REF1
Is+1
FB1
FS1
A
GND
MCTL
FS2
FB2
Is+2
EXTVCC
REG2
REG1
VIN
LG2
PGND2
FIN
BD9524MUV
Technical Note
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Reference data
Fig.1 wake up (Vo=5.0V) Fig.2 wake up (Vo=3.3V)
Fig.4 CONT Mode (Io=0A) Fig.5 CONT Mode (Io=0.4A) Fig.6 CONT Mode (Io=1.4A)
Fig.7 QLLM (Io=0A) Fig.8 QLLM (Io=0.4A) Fig.9 QLLM (Io=1.4A)
Fig.10 SLLM (Io=0A) Fig.11 SLLM (Io=0.4A) Fig.12 SLLM (Io=1.4A)
Fig.3 wake up (REG1, REG2)
EN
5V/div
PGOOD
5V/div
SS
1V/div
Vo
2V/div
EN
5V/div
PGOOD
5V/div
SS
1V/div
Vo
2V/div
Vo
20mV/di
v
IL
2A/div
SW
5V/div
LG
5V/div
Vo
20mV/di
v
IL
2A/di
v
SW
5V/di
v
LG
5V/di
v
Vo
20mV/di
v
IL
2A/div
SW
5V/div
LG
5V/div
Vo
20mV/di
v
IL
2A/div
SW
5V/div
LG
5V/div
Vo
20mV/di
v
IL
2A/di
v
SW
5V/di
v
LG
5V/di
v
Vo
20mV/di
v
IL
2A/di
v
SW
5V/di
v
LG
5V/di
v
Vo
20mV/di
v
IL
2A/div
SW
5V/div
LG
5V/div
Vo
20mV/di
v
IL
2A/di
v
SW
5V/di
v
LG
5V/di
v
Vo
20mV/di
v
IL
2A/div
SW
5V/div
LG
5V/div
CTL
10V/div
REG1
2V/div
REG2
2V/div
BD9524MUV
Technical Note
7/20
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© 2010 ROHM Co., Ltd. All rights reserved.
Reference data
0.0
0.5
1.0
1.5
0.00 0.40 0.80 1.20 1.60
FS[V]
ON TIME[usec]
Fig.13 FS-ON TIME
Vo=5.0V
Vo=3.3V
0.1
1
10
100
7 101316192225
VIN [V]
IVIN [mA]
Fig.17 VIN-IVIN (Io=0A, Vo1=5.0V)
CONT Mode
SLLM
QLLM
0
200
400
600
800
1000
1200
0.00 0.40 0.80 1.20 1.60
FS[V]
Frequency[kHz]
Fig.14 FS-frequency
QLLM, SLLM (3.3V)
QLLM, SLLM (3.3V)
CONT Mode (3.3V)
CONT Mode (5.0V)
VIN=12V, Vo=5.0V
0
10
20
30
40
50
60
70
80
90
100
1 10 100 1000 10000
Io [mA]
efficiency [%]
Fig.16 Io-efficiency (VIN=12V, Vo1=5.0V)
QLLM
SLLM
CONT Mode
0
50
100
150
200
250
300
350
400
450
500
0.001 0.01 0.1 1 10
Io [A]
frequency [KHz]
CONT Mode
(
VIN=7
)
CONT Mode (VIN=12)
CONT Mode (VIN=19)
(VIN=7, 12, 19V)
QLLM
SLLM
QLLM
,
SLLM
(
VIN=7
)
QLLM,SLLM (VIN=12)
Fig.15 Io-frequency (Vo1=5.0V)
QLLM,SLLM (VIN=19)
BD9524MUV
Technical Note
8/20
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Pin Descriptions
VIN
This is the main power supply pin. The input supply volt age range is 7 V to 25V. The duty cycle of BD9524MUV is determined b y
input voltage and control ou tput volt age. Therefore, when VIN voltage fluctuated, the ou tput volt age also beco mes unstable .
Since VIN line is also the input voltage o f sw itching regulator, stability depends on the impedance of the volta ge supply. It is
recommended to establish by pa ss cap acitor a nd CR fil ter suit able for the actu al application.
CTL
When CTL pin volt age is at least 2.3V the st atus of the linear re gulator output b ecomes active (REG1 =5V, REG2=3.3V).
Conversely, the status switches of f when CTL pin volt age goes low er than 0.8V. The sw itching regulator doesn’t become active
when the status of CTL pin is low, if the status of EN pin is high.
EN
When EN pin voltage is at lea st 2.3V, the statu s of the sw itching regulato r becomes acti ve. Conversely, the sta tus switches of f
when EN pin voltage goes low er than 0.8V.
REG1
This is the output pin for 5 V linear regulat or and also acti ve in power supply for driver and con trol circuit of the inside. The
standby functio n for REG1 is determined by CTL pin. The vol t age is 5V, with 100mA current ability. It is recommended that a
10uF capacitor (X5R or X7R) be est ablished betw een REG1 and GND.
REG2
This is the output pin for 3 .3V li near regulator. The standby function for REG2 is determined by CTL. The volt age is 3.3V, w ith
100mA curren t ability. It is recommended that a 10uF capacitor (X5R or X7R) be est ablished between REG2 and GND. It is
available to set REF and SS by the resistance division value from REG2 in case REF are not set from an external pow er supply.
EXTVCC
This is the external input pin to REG1. When EXTVCC is beyond 4.4V, it supplies REG1 a s EXTVCC is the p ower supply.
REF
This is the setting pin for outpu t volt age of sw itching regulator. It is so convenient to be sy nchronized to out side pow er supp ly.
This IC controls the vo lt age in the st atus of 2 ×REFFB.
FB
This is the feedback pin from th e output of switching regulato r. This IC controls the vol tage in the status of 2 ×REFFB.
SS
This is the settin g pin for sof t sta rt. The rising time is determined by the capacitor connected between SS and GND, and the fixed
current inside IC af ter it is the statu s of low in st andby mode. It controls the output volt age till SS volt age catch up the RE F pin to
become the double of the SS terminal voltage .
FS
This is the input pin for setting the frequency. It is available to set it in frequency range is 200KHz to 500kHz.
Is+
This is the sense pin for output current. In ca se it is connected to side o f the coi l resist ance for sense cu rrent and the volt age is
set 65mV(typ) or more higher th an FB pin vo l ta ge, the switching operation turns OFF.
PGOOD
This is the open drain pin for deciding the output of switching re gulator.
MCTL
This is the switching shif t pin for SLLM (Si mple Light Load Mod e). The ef ficiency in SLLM mod e improves in setting MC TL pin to
1.5V or more. In case MCTL terminal vol tage ra nge is fro m 1.5 to 3.0V, LG maximum OFF time is 40usec, from 4.5V to
REG1+0.3V, LG maximum OFF time is to infinity. It is in contin uous mode tha t MCTL pin volt age is set 0 .3V or less.
AGND,DGND
This is the ground pin.
BOOT
This is the power supply pin for high side FET driver. The maximum voltage range to GND pin is to 35V, to SW pin is to 7V. In
switching operations, the volt age sw ings from (VIN+REG1) to REG1 by BOOT pin operation.
HG
This is the highside FET gate d rive pin. It i s operated in swit ching between BOOT to SW. In ca se the output MOS is 3ohm /the
status of Hi, 2o hm/the sta tus of Low, it is ope rated hi-side FET gate in high speed.
SW
This is the ground pin for high side FET drive. The maximum voltage range to GND pin is to 30V. Sw itching operation sw ings
from the status of BOOT to the st atus of GND.
LG
This is the lowside FET gate dri ve pin. It is operated in sw itching between REG1 to PGND. In case the output MOS is 2ohm /the
status of Hi, 0 .5ohm/the sta tus of Low, it is operated low-side FET ga te in high speed.
PGND
This is the ground pin for low side FET drive.
BD9524MUV
Technical Note
9/20
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Explanation of Operation
The BD9524MUV is a 2ch s y nchronous buck regulator controller incorporating ROHM’s proprietary H3RegTM CONTROLLA
control system. When VOUT drops due to a rapid load change, the system quickly restores VOUT by extending the TON
time interval. Thus, it serves to improve the regulator’s transient response. Activating the Light Load Mode will also exercise
Simple Light Load Mode (SLLM) control when the load is light, to further increase efficiency.
H3RegTM control
(Normal operation)
(VOUT drops due to a rapid load change)
Light Load Control
(SLLM)
(QLLM)
*Attention: H3RegTM CONTROLLA monitors the supplying current
from capacitor to load, using the ESR of output capacitor,
and realize the rapid respo nse. Bypass capacitor used at
each load (Ex. Ceramic capacitor) exercise the effect
with connecting to each load side. Do not put a ceramic
capacitor on COUT side of power supply.
HG output is determined by the formula above.
When VOUT falls to a reference voltage (2×REF), the drop
is detected, activating the H3RegTM CONTROLLA system.
When VOUT drops due to a rapid load chan ge, and the
voltage remains below reference voltage after the
programmed tON time interval has elapsed, the system
quickly restores VOUT by extending the tON time, improving
the transient response.
tON=2×REF
VIN × 1
f [sec]・・・(1)
In SLLM (MCTL=”High voltage”), when the status of LG is
OFF and the coil current is within 0A (it flows to SW from
VOUT.), SLLM function is operated to prevent output next
HG. The status of HG is ON, when VOUT falls belo
w
reference voltage again.
In QLLM (MCTL=”Hiz or Middle voltage”), when the status
of LG is OFF and the coil current is within 0A (it flows to
SW from VOUT.), QLLM function is operated to prevent
output next HG.
Then, VOUT falls below the output programmed voltage
within the programmed time (typ=40μs), the status of HG
is ON. In case VOUT doesn’t fall in the programmed time,
the status of LG is ON forcedly and VOUT falls. As a result,
he status of next HG is ON.
VOUT
2×REF
HG
LG
VOUT
HG
Io
LG
tON+α
VOUT
2×REF
HG
LG
0
A
VOUT
2×REF
HG
LG
0
Load
COUT
BD9524MUV
Technical Note
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Timing Chart
Soft Start Function Soft start is exercised with the EN pin set high. Current
control takes effect at startup, enabling a moderate output
voltage “ramping start.” Soft start timing and incoming
current are calculated with formulas (2) and (3) below.
Soft start time
(Css: Soft start capacitor; Co: Output capacitor)
Timer Latch Type Short Circuit Protection
Short protection kicks in when output falls to or below
REF × 1.4 (setting voltage × 0.7).
When the programmed time period elapses, output is
latched OFF to prevent destruction of the IC. Output
voltage can be restored either by reconnecting the EN pin
or disabling UVLO.
Over Voltage Protection
Over current protection circuit
EN
SS
VOU
T
IIN
TSS
Tss= REF×Css
2μA(typ) [sec]
Incoming current
IIN= Co×VOUT
Tss
[A]
・・・(2)
・・・(3)
VOU
T
SCP
EN / UVLO
REF
×
1.4
150μs(typ)
or more
150μs(typ)
or less
150μs(typ)
Latch
VOUT
REF×2.35
OVP
EN / UVLO
When output rise to or above REF×2.35
(output setting voltage ×1.175), output over voltage
protection is exercised, and low side F ET goes up
maximum for reducing output.LG=High, HG=Low. When
output falls within the progra mmed time (typ=150μs), it
returns to the standard mode. When the programmed time
period elapses, output is latched OFF to prevent
destruction of the IC. Output voltage can be restored eithe
r
by reconnecting the EN pin or disabling UVLO.
During the normal operation, when VOUT becomes less
than reference voltage, HG becomes High during the
time tON . However, when inductor current exceeds
ILIMIT threshold, HG becomes OFF.
A
fter 2.5μsec(typ), HG becomes ON again if the output
voltage is lower than the specific voltage level and IL is
lower than ILIMIT level.
2.5usec
tON tON
HG
LG
IL
ILIMIT
tON
2×REF
increase Io
Vo
BD9524MUV
Technical Note
11/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
External Component Selection
1. Inductor (L) selection
Passing a current larger than the inductors rated current will cause magnetic saturation in the inductor and decrease
system efficiency. In selecting the inductor, be sure to allow enough margin to assure that peak current does not exceed
the inductor rated current value.
To minimize possible inductor damage and maxim ize efficiency, choose a inductor with a lo w (DCR, ACR) resistance.
2.Output Capacitor (CO) Selection
Please give due consideration to the conditions in formula (8) below for output capacity, bear in mind that output rise time
must be established within the soft start time frame.
Note: Improper capacitor may cause startup malfunctions.
3. Input Capacitor (Cin) Selection
A low ESR capacitor is recommended to reduce ESR loss and maximize efficiency.
The inductor value is a major influence on the output ripple
current. As formula (4) below indicates, the greater the inductor o
r
the switching frequency, the lower the ripple current.
ΔIL=(VIN-VOUT)×VOUT
L×VIN×f [A]・・・
(
4
)
The proper output ripple current setting is about 30% of maximum
out
p
ut current.
ΔIL=0.3×IOUTmax. [A]・・・(5)
L= (VIN-VOUT)×VOUT
ΔIL×VIN×f
[
H
]
・・・
(
6
)
(ΔIL: output ripple current; f: switch frequency)
When determining the proper output capacitor, be sure to factor in the equivalent
series resistance required to smooth out ripple volume and maintain a stable
output voltage range.
Output ripple voltage is determined as in formula (7) b elow.
ΔVOUT=ΔIL×ESR [V]・・・(7)
(ΔIL: Output ripple current; ESR: CO equivalent series resistance)
In selecting a capacitor, make sure the capacitor rating allows sufficient
margin relative to output voltage. Note that a lower ESR can minimize output
ripple voltage.
Tss: Soft start time
Limit: Over current detection 2A(Typ)
Input Capacitor
The input capacitor selected must have low enough ESR resistance to fully
support large ripple output, in order to prevent extreme over current. The
formula for ripple current IRMS is given in (9) below.
IRMS=IOUT× VIN
(
VIN-VOUT
)
VIN
[
A
]
・・・
(
9
)
Where VIN=2×VOUT,IRMS= IOUT
2
ΔIL
VIN
IL
L Co
VOUT
Output ripple current
Output Capacitor
VIN
L Co
VOUT
Cin
VIN
L
Co
VOUT
ESR Load
CEXT
Co+CEXT TSS×(Limit-IOUT)
VOUT ・・・
(
8
)
BD9524MUV
Technical Note
12/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
4. MOSFET Selection
5. Setting Detection Resistance (Detect ILIMIT at the peak current)
(A) High accuracy current detective circu it (use the low resistance)
(B) Low loss current detective circuit (use the DCR value of inductor)
(C) Low loss current detective circuit (the DCR value of inductor : high)
The over current protection function detects the output ripple
current peak value. This parameter (setting value) is
determined as in formula (13) below.
65mV(typ)
R
ILMIT=
(R: Detection resistance)
VIN
L
Co
VOUT
synchronous switch
main switch Pmain=PRON+PGATE+PTRAN
Psyn=PRON+PGATE
VOUT
VIN ×RON×IOUT2+Ciss×f×VDD+ VIN2×Crss×IOUT×f
IDRIVE
VIN-VOUT
VIN ×RON×IOUT2+Ciss×f×VDD
Loss on the main MOSFET
(Ron: On-resistance of FET; Ciss: FET gate capacitance;
f: Switching frequency Crss: FET inverse transfer function;
IDRIVE: Gate peak current)
Loss on the synchronous MOSFET
=・・・(10)
=・・・(11)
[A]・・・(12)
ILMIT=65mV(typ)×
When the over current protection is detected by DCR of inductor L,
this parameter (setting value) is determined as in formula (13)
below.
(Application circuit:P18)
r×C
L
(RL: the DCR value of inductor)
[A]・・・(13)
L
r×C
(RL=)
VIN
L
Co
VOUT
Current limit
IL
R
65mV
OCP
VIN
L
Co
VOUT
Current limit
IL
RL
r C
65mV
OCP
(RL: the DCR value of inductor)
65mV(typ)
k×RL
ILIMIT=[A]・・・(14)
VIN
L
Co
VOUT
IL
(1-k)RL
R1
C
Current limit
65mV
R2
kRL ( RL
L
k= R1+R2
R2= kR1C ) ,
BD9524MUV
Technical Note
13/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
6. Setting standard voltage (REF)
REF= ×REG2 [V]・・・(15)
7. Setting output voltage
This IC is operated that output voltage is REF×2FB.
And it is operated that output voltage is feed back to FB pin.
REF
FB
R0
R0
It is available to set the reference voltage (REF)
by the resistance division value from REG2 in
case REF is not set from an external powe
r
supply.
FB
R0
R0
H3RegTM
CONTROLLA S
RQ
VIN
REG2(3.3V)
R1
R2
REF
It is available to set the reference voltage (REF)
with outside supply voltage ×2 [V] by using
outside power supply voltage.
H3RegTM
CONTROLLA S
RQ
VIN
REF
R1+R2
R2
H3RegTM
CONTROLLA S
RQ SLLM
Driver
Circuit
SLLM
VIN
Output
voltage
VIN
FB
R0
R0
Outside
voltage
BD9524MUV
Technical Note
14/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
I/O Equivalent Circuit
1, 24pin (SW2, SW1) 2, 23pin (HG2, HG1) 3, 22pin (BOOT2, BOOT1)
4, 21pin (EN2, EN1) 5, 20pin (PGOOD2, PGOOD1) 6, 19pin (SS2, SS1)
8, 17pin (REF2, REF1) 9, 16pin (Is+2, Is+1) 10, 15pin (FB2, FB1)
11, 14p in (F S2, F S 1) 12pin (MCTL) 18pin (CTL)
BOOT BOOT
SW
REG1
HG
SW
REG1
HG
BOOT
BD9524MUV
Technical Note
15/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
I/O Equivalent Circuit
26, 31pin (LG1, LG2) 27pin (EXTVCC) 28pin (REG2)
29pin (REG1) 30pin (VIN)
Evaluation Board Circuit (Vo1=5V f1=300kHz Vo2=3.3V f2=400kHz)
REG1 REG1
REG1
VIN
REG1
VIN
CTL
EN1
EN2
REG1
REG2
EXTVCC
REF1
REF2
SS1
FS1
BOOT1
HG1
SW1
LG1
PGND1
Is+1
FB1
BOOT2
HG2
SW2
LG2
PGND2
Is+2
VIN
12V
C1
CTL
R2
EN1
R3
EN2
R4
CTL
EN1
EN2
VIN
REG1
REG1
REG1
5V
REG2
3.3
V
EXTVCC
C2
C3
C4
REG2
R6
REG2
R8
R7 C5
R9 C6
C8 C7
FS1
R17 C18 R25
Q3
Q4
D4 C17
REG1 VIN VIN
C15 C16
SW2
D2
R39
R40
Q1
Q2
C24
D3 C27
VIN VIN
C25 C26
SW1
D1
30
18
21
4
29
28
27
17
8
19
6
14
22
23
24
26
25
16
15
3
2
1
31
32
9
BD9524MUV
R1
R5
Vo1
R16
REG2 VIN
R58
REG2
VIN
C19
R35
R32
R34
R30
R47
R49
R50
R46
L2 R33
R29
R28
VO2
C12
C11 C30 C29 C10
R31 C36 C13
R15
R26
R27
R18
C37
R22
L1 R48
R44 R43
R45 C34 C23
R10
R41
R42
R11
C35
R19
R56
R55
R57
Q5
TPQ6
VO1
C22
C21 C32
C33 C20
FS2
11
MCTL
DGND
A
GND
FB2
PGOOD1
PGOOD2
C14
R24
REG1
REG1 PGOOD2
PGOOD1
12
7
13
C28
C31
R14
MCTL
10
20
5
R20
R36
R21
R37
R13 R12 FS2 C9
R63
R52
R54
Q6
SS2
TPQ5
BD9524MUV
Technical Note
16/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
DESIGNATION RATING PART No. COMPANY
DESIGNATION RATING PART No. COMPANY
R1 0 MCR03EZHJ000 ROHM
R58 1M MCR03PZHZF1004 ROHM
R2 0 MCR03EZHJ000 ROHM
R63 - - -
R3 0 MCR03EZHJ000 ROHM
C1 10uF(25V) CM32X7R106M25A KYOCERA
R4 0 MCR03EZHJ000 ROHM
C2 10uF(6.3V) GRM21BB10J106KD MURATA
R5 0 MCR03EZHJ000 ROHM
C3 10uF(6.3V) GRM21BB10J106KD MURATA
R6 15k MCR03PZHZF1502 ROHM
C4 10uF(6.3V) GRM21BB10J106KD MURATA
R7 47k MCR03PZHZF4702 ROHM
C5 0.01uF(50V) GRM188B11H103KD MURATA
R8 30k MCR03PZHZF3002 ROHM
C6 0.01uF(50V) GRM188B11H103KD MURATA
R9 30k MCR03PZHZF3002 ROHM
C7 1000pF(50 V) GRM188B11H102KD MURATA
R10 * - - -
C8 1000pF(50V) GRM188B11H102KD MURATA
R11 * - - -
C9 - - -
R12 - - -
C10 - - -
R13 1M MCR03PZHZF1004 ROHM
C11 220uF 6TPE220MI SANYO
R14 51k MCR03PZHZF5102 ROHM
C12 - - -
R15 * - - -
C13 * - - -
R16 - - -
C14 0.47uF(10V) GRM188B11A474KD MURATA
R17 36k MCR03PZHZF3602 ROHM
C15 10uF(25V) CM32XR7106M25A KYOCERA
R18 * - - -
C16 10uF(25V) CM32XR7106M25A KYOCERA
R19 * - - -
C17 10uF(6.3V) GRM21BB10J106KD MURATA
R20 100k MCR03PZHZF1003 ROHM
C18 - - -
R21 0 MCR03EZHJ000 ROHM
C19 - - -
R22 * - - -
C20 - - -
R24 0 MCR03EZHJ000 ROHM
C21 220uF 6TPE220MI SANYO
R25 0 MCR03EZHJ000 ROHM
C22 - - -
R26 * - - -
C23 * - - -
R27 * - - -
C24 0.47uF(10V) GRM188B11A474KD MURATA
R28 0 MCR03EZHJ000 ROHM
C25 10uF(25V) CM32XR7106M25A KYOCERA
R29 0 MCR03EZHJ000 ROHM
C26 10uF(25V) CM32XR7106M25A KYOCERA
R30 0 MCR03EZHJ000 ROHM
C27 10uF(6.3V) GRM21BB10J106KD MURATA
R31 * - - -
C28 - - -
R32 0 MCR03EZHJ000 ROHM
C29 - - -
R33 5m PMR100HZPFU5L00 ROHM
C30 - - -
R34 0 MCR03EZHJ000 ROHM
C31 - - -
R35 0 MCR03EZHJ000 ROHM
C32 - - -
R36 100k MCR03PZHZF1003 ROHM
C33 - - -
R37 0 MCR03EZHJ000 ROHM
C34 * - - -
R39 0 MCR03EZHJ000 ROHM
C35 * - - -
R40 0 MCR03EZHJ000 ROHM
C36 * - - -
R41 * - - -
C37 * - - -
R42 * - - -
D1 Diode RSX501L-20 ROHM
R43 0 MCR03EZHJ000 ROHM
D2 Diode RSX501L-20 ROHM
R44 0 MCR03EZHJ000 ROHM
D3 Diode RB520S-30 ROHM
R45 * - - -
D4 Diode RB520S-30 ROHM
R46 0 MCR03EZHJ000 ROHM
L1 2.5uH
CDEP105NP-2R5MC-
32 Sumida
R47 0 MCR03EZHJ000 ROHM
L2 2.5uH
CDEP105NP-2R5MC-
32 Sumida
R48 5m PMR100HZPFU5L00 ROHM
Q1 FET uPA2702 NEC
R49 0 MCR03EZHJ000 ROHM
Q2 FET uPA2702 NEC
R50 0 MCR03EZHJ000 ROHM
Q3 FET uPA2702 NEC
R52 - - -
Q4 FET uPA2702 NEC
R54 - - -
Q5 - - -
R55 - - -
Q6 - - -
R56 - - -
U1 - BD9524MUV ROHM
R57 - - -
* Patterns for over current detection used DCR.
BD9524MUV
Technical Note
17/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
Handling method of unused pin during using onl y 1ch DC/DC.
If using only 1ch DC/DC and 2ch pin is set to be off at all times, please manage the unused pin as d iagram below.
PIN No, PIN Name Management
1 SW2 GND
2 HG2 OPEN
3 BOOT2 GND
4 EN2 GND
5 PGOOD2 GND
6 SS2 GND
8 REF2 GND
9 Is+2 GND
10 FB2 GND
11 FS2 GND
31 LG2 OPEN
REG1
VIN
CTL
EN1
EN2
REG1
REG2
EXTVCC
REF1
REF2
SS1
FS1
BOOT1
HG1
SW1
LG1
PGND1
Is+1
FB1
BOOT2
HG2
SW2
LG2
PGND2
Is+2
VIN
12V
C1
CTL
R2
EN1
R3
CTL
EN1
VIN
REG1
REG1
5V
REG2
3.3
V
EXTVCC
C2
C3
C4
REG2
R6
R7 C5
C7
FS1
R17 C18
R39
R40
Q1
Q2
C24
D3 C27
VIN VIN
C25 C26
SW1
D1
30
18
21
4
29
28
27
17
8
19
6
14
22
23
24
26
25
16
15
3
2
1
31
32
9
BD9524MUV
R1
R5
Vo1
R16
REG2 VIN
R58
C19
R47
R49
R50
R46
L1 R48
R44
R43
R45 C34 C23
R10
R41
R42
R11
C35
R19
R56
R55
R57
Q5
TPQ6
VO1
C22
C21 C32
C33 C20
FS2
11
MCTL
DGND
A
GND
FB2
PGOOD1
PGOOD2
REG1 PGOOD1
12
7
13
C28
MCTL
10
20
5
R20
R21
SS2
VO1
R51 R60
BD9524MUV
Technical Note
18/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
Notes for use
1. This integrated circuit is a monolithic IC, which (as shown in the figure below), has P isolation in the P substrate and
between the various pins. A P-N junction is formed from this P layer and N layer of each pin, with the type of junction
depending on t he relation between eac h potential, as follows:
When GND> element A> element B, the P-N junction is a diode.
When element B>GND element A, the P-N junction operates as a parasitic transistor.
Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, as well as operating malfunctions and physical damage. Therefore, be careful to avoid
methods by which parasitic diodes operate, such as applying a voltage lower than the GND (P substrate) voltage to an
input pin.
2. In some modes of operation, power supply voltage and pin voltage are reversed, giving rise to possible internal circuit
damage. For example, when the external capacitor is charged, the electric charge can cause a VCC short circuit to the
GND. In order to avoid these problems, inserting a VCC series countercurrent prevention diode or bypass diode between
the various pins and the VCC is recommended.
3. Absolute maximum rating
Although the quality of this IC is rigorously controlled, the IC may be destroyed when applied voltage or operating
temperature exceeds its absolute maximum rating. Because short mode or open mode cannot be specified when the IC is
destroyed, it is important to take physical safety measures such as fusing if a special mode in excess of absolute rating
limits is to be implemented.
4.GND potential
Make sure the potential for the GND pin is alwa ys kept lo wer than the potentials of all other pins, regardless of the
operating mode.
5. Thermal design
In order to build sufficient margin into the thermal design, give proper consideration to the allowable loss (Power
Dissipation) in actual operation.
6. Short-circuits between pins and incorrect mounting position
When mounting the IC onto the circuit board, be extremely careful about the orientation and position of the IC. The IC may
be destroyed if it is incorrectly positioned for mounting. Do not short-circuit between any output pin and supply pin or
ground, or between the output pins themselves. Accidental att achment of small objects on these pins will cause shorts and
may damage the IC.
VCC
Pin
Countercurrent
Bypass diode
Resistor Transistor (NP N)
N
N N P+ P
+
P
P substrate
GND
Parasitic element
Pin A
N
N P+ P+
P
P substrate
GND
Parasitic element
Pin B C B
E
N
GND
Pin A
P
aras
iti
c
element
Pin B
Other adjacent elements
E
B C
GND
P
aras
iti
c
element
BD9524MUV
Technical Note
19/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
7. Operation in strong electromagnetic fields
Use in strong electromagnetic fields may ca use malfunctions. Use extreme caution with electromagnetic fields.
8. Thermal shutdown circuit
This IC is provided with a built-in thermal shutdown (TSD) circuit, which is activated when the operating temperature
reaches 175 (standard value), and has a hysteresis range of 15 (standard). When the IC chip temperature rises to
the threshold, all the inputs automatically turn OFF. Note that the TSD circuit is provided for the exclusive purpose shutting
down the IC in the presence of extreme heat, and is not designed to protect the IC per se or guarantee performance when
or after extreme heat conditions occur. Therefore, do not operate the IC with the expectation of continued use or
subsequent operation once the TSD is activated.
9. Capacitor between output and GND
When a larger capacitor is connected between the output and GND, Vcc or VIN shorted with the GND or 0V line – for any
reason – may cause the charged capacitor current to flow to the output, possibly destroying the IC. Do not connect a
capacitor larger than 1000uF between the output and GND.
10. Precautions for board inspection
Connecting low-impedance capacitors to run inspections with the board may produce stress on the IC. Therefore, be
certain to use proper discharge procedure before each process of the operation. To prevent electrostatic accumulation and
discharge in the assembly process, thoroughly ground yourself and any equipment that could sustain ESD damage, a nd
continue observing ESD-prevention procedu res in all handling, transfer and storage operations. Before attempting to
connect components to the test setup, make certain that the power supply is OFF. Likewise, be sure the power supply is
OFF before removing any component connected to the test setup.
11. GND wiring pattern
When both a small-signal GN D and high current GND are present, single-point grounding (at the set standard point) is
recommended, in order to separate the small-signal and high current patterns, and to be sure the voltage change
stemming from the wiring resistance and high current does not cause any voltage change in the small-signal GND. In the
same way, care must be taken to avoid wiring pattern fluctuations i n any connected external com ponent GND.
Power Dissipation
Ambient Temperature [Ta]
Power Dissipation [Pd]
150 125 100 75 50 25 0
200
400
600
800
1000
[]
[mW]
880mW
380mW
70mm×70mm×1.6mm Glass-e
p
ox
y
PCB
θj-a=142.0/W
With no heat sink θj-a=328.9/W
BD9524MUV
Technical Note
20/20
www.rohm.com 2010.03 - Rev.C
© 2010 ROHM Co., Ltd. All rights reserved.
Ordering part number
B D 9 5 2 4 M U V - E 2
Part No. Part No.
Package
MUV : VQFN032V5050 Packaging and forming specification
E2: Embossed tape and reel
(Unit : mm)
VQFN032V5050
0.08 S
S
1.0MAX
(0.22)
0.02+0.03
-
0.02
24
81
9
32
16
25 17
0.5
0.75
0.4±0.1
3.4±0.1
3.4±0.1
0.25 +0.05
-
0.04
C0.2
5.0±0.1
5.0±0.1
1PIN MARK
Order quantity needs to be multiple of the minimum quantity.
<Tape and Reel information>
Embossed carrier tapeTape
Quantity
Direction
of feed
The direction is the 1pin of product is at the upper left when you hold
reel on the left hand and you pull out the tape on the right hand
2500pcs
E2
()
Direction of feed
Reel 1pin
Datasheet
Datasheet
Notice - GE Rev.002
© 2014 ROHM Co., Ltd. All rights reserved.
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
intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Note 1), transport
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
CLASS CLASS CLASSb CLASS
CLASS CLASS
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
Datasheet
Datasheet
Notice - GE Rev.002
© 2014 ROHM Co., Ltd. All rights reserved.
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.
DatasheetDatasheet
Notice – WE Rev.001
© 2014 ROHM Co., Ltd. All rights reserved.
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 any damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or
concerning such information.