ROHM BD8961NV

4.5V to 5.5V, 2.0A 1ch
Synchronous Buck Converter Integrated FET
BD8961NV
●General Description
ROHM’s high efficiency step-down switching
regulator BD8961NV is a power supply designed to
produce a low voltage including 3.3 volts from 5
volts power supply line. Offers high efficiency with
synchronous rectifier. Employs a current mode
control system to provide faster transient response
to sudden change in load.
●Key Specification
 Input voltage range:
 Output voltage range:
 Output current:
 Switching frequency:
 Pch FET ON resistance:
 Nch FET ON resistance:
 Standby current:
 Operating temperature range:
●Features
 Offers fast transient response with current mode
PWM control system.
 Offers highly efficiency for all load range with
synchronous rectifier (Nch/Pch FET)
 Incorporates soft-start function.
 Incorporates thermal protection and ULVO
functions.
 Incorporates short-current protection circuit with
time delay function.
 Incorporates shutdown function
●Packages
SON008V5060
4.5V to 5.5V
3.3V(Typ.)
2.0A (Max.)
1.0MHz(Typ.)
200mΩ(Typ.)
150mΩ(Typ.)
0μA (Typ..)
-25℃ to +105℃
5.0mm x 6.0mm x 1.0mm
●Applications
Power supply for LSI including DSP, Micro computer
and ASIC
●Typical Application Circuit
VCC
Cin
L
VCC,PVCC
EN
VOUT
SW
VOUT
VOUT
ESR
ITH
GND,PGND
RO
CO
RITH
CITH
Fig.1 Typical application
○Product structure:Silicon monolithic integrated circuit
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Datasheet
BD8961NV
●Pin Configuration
TOP VIEW
VOUT
1
8
EN
VCC
2
7
PVCC
ITH
3
6
SW
GND
4
5
PGND
Fig.2 Pin Configuration
●Pin Description
Pin No.
1
2
3
4
5
6
7
8
Pin name
VOUT
VCC
ITH
GND
PGND
SW
PVCC
EN
PIN function
Output voltage pin
VCC power supply input pin
GmAmp output pin/Connected phase compensation capacitor
Ground
Nch FET source pin
Pch/Nch FET drain output pin
Pch FET source pin
Enable pin (Active High)
●Block Diagram
Fig.3 Block Diagram
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Datasheet
BD8961NV
●Absolute Maximum Ratings
Parameter
VCC Voltage
PVCC Voltage
EN Voltage
SW,ITH Voltage
Symbol
Ratings
VCC
PVCC
Unit
-0.3 to +7
*1
V
-0.3 to +7
*1
V
VEN
-0.3 to +7
V
VSW,VITH
-0.3 to +7
Power Dissipation 1
Pd1
900*
Power Dissipation 2
Pd2
3900*
mW
Operating temperature range
Topr
-25 to +105
℃
Storage temperature range
Tstg
-55 to +150
℃
Tjmax
+150
℃
Maximum junction temperature
*1
*2
*3
V
2
mW
3
Pd should not be exceeded.
Derating in done 7.2mW/℃ for temperatures above Ta=25℃, Mounted on 70mm×70mm×1.6mm Glass Epoxy PCB (the density of copper:3%)
Derating in done 31.2mW/℃ for temperatures above Ta=25℃, Mounted on JESD51-7.
●Operating Ratings (Ta=25℃)
Parameter
VCC Voltage
Symbol
*4
VCC
PVCC Voltage
PVCC
EN Voltage
VEN
SW average output current
*4
Isw
*4
*4
Ratings
Unit
Min.
Typ.
Max.
4.5
5.0
5.5
V
4.5
5.0
5.5
V
0
-
VCC
V
-
-
2.0
A
Pd should not be exceeded.
●Electrical Characteristics(Ta=25℃, VCC=PVCC=3.3V, EN=VCC.)
Parameter
Standby current
Bias current
EN Low voltage
EN High voltage
EN input current
Oscillation frequency
Pch FET ON resistance
Nch FET ON resistance
Output voltage
ITH SInk current
ITH Source Current
UVLO threshold voltage
UVLO release voltage
Soft start time
Timer latch time
Output Short circuit Threshold Voltage
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Symbol
ISTB
ICC
VENL
VENH
IEN
FOSC
RONP
RONN
VOUT
ITHSI
ITHSO
VUVLO1
VUVLO2
TSS
TLATCH
VSCP
Min.
2.0
0.8
3.250
10
10
3.6
3.65
0.5
1
-
3/16
Limits
Typ.
0
250
GND
VCC
1
1
200
150
3.300
20
20
3.8
3.90
1
2
1.65
Max.
10
450
0.8
10
1.2
320
270
3.350
4.0
4.2
2
3
2.31
Unit
μA
μA
V
V
μA
MHz
mΩ
mΩ
V
μA
μA
V
V
ms
ms
VOUT
Conditions
EN=GND
Standby mode
Active mode
VEN=5V
PVCC=5V
PVCC=5V
VOUT=3.6V
VOUT=3.0V
VCC=5→0V
VCC=0→5V
SCP/TSD operated
VOUT=3.3→0V
TSZ02201-0J3J0AJ00020-1-2
02.MAR.2012 Rev.001
Datasheet
BD8961NV
●Typical Performance Curves
Fig.4 Vcc-Vout
Fig.5 Ven-Vout
Fig.7 Ta-VOUT
Fig.6 Iout-Vout
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Datasheet
BD8961NV
Fig.9 Ta-FOSC
Fig.8 Efficiency
Fig.11 Ta-VEN
Fig.10 Ta-RONN, RONP
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Datasheet
BD8961NV
Fig.13 Vcc-Fosc
Fig.12 Ta-ICC
Fig.15 SW waveform Io=10mA
Fig.14 Soft start waveform
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Datasheet
BD8961NV
Fig.17 Transient response
Io=2A→1A(10μs)
Fig. 16 Transient response
Io=1A→2A(10μs)
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Datasheet
BD8961NV
●Application Information
Operation
BD8961NV is a synchronous rectifying step-down switching regulator that achieves faster transient response by employing
current mode PWM control system.
○Synchronous rectifier
It does not require the power to be dissipated by a rectifier externally connected to a conventional DC/DC converter IC,
and its P.N junction shoot-through protection circuit limits the shoot-through current during operation, by which the power
dissipation of the set is reduced.
○Current mode PWM control
Synthesizes a PWM control signal with a inductor current feedback loop added to the voltage feedback.
・PWM (Pulse Width Modulation) control
The oscillation frequency for PWM is 1 MHz. SET signal form OSC turns ON a P-channel MOS FET (while a
N-channel MOS FET is turned OFF), and an inductor current I L increases. The current comparator (Current Comp)
receives two signals, a current feedback control signal (SENSE: Voltage converted from I L) and a voltage feedback
control signal (FB), and issues a RESET signal if both input signals are identical to each other, and turns OFF the
P-channel MOS FET (while a N-channel MOS FET is turned ON) for the rest of the fixed period. The PWM control
repeat this operation.
SENSE
Current
Comp
RESET
VOUT
Level
Shift
R Q
FB
SET
Gm Amp.
ITH
S
IL
Driver
Logic
VOUT
SW
Load
OSC
Fig.18 Diagram of current mode PWM control
PVCC
Current
Comp
SENSE
FB
SET
GND
RESET
GND
SW
GND
IL
IL(AVE)
VOUT
VOUT(AVE)
Fig.19 PWM switching timing chart
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Datasheet
BD8961NV
Description of Operations
・Soft-start function
EN terminal shifted to “High” activates a soft-starter to gradually establish the output voltage with the current limited
during startup, by which it is possible to prevent an overshoot of output voltage and an inrush current.
・Shutdown function
With EN terminal shifted to “Low”, the device turns to Standby Mode, and all the function blocks including reference
voltage circuit, internal oscillator and drivers are turned to OFF. Circuit current during standby is 0μF (Typ.).
・UVLO function
Detects whether the input voltage sufficient to secure the output voltage of this IC is supplied.
of 100mV (Typ.) is provided to prevent output chattering.
And the hysteresis width
Hysteresis 100mV
VCC
EN
VOUT
Tss
Tss
Tss
Soft start
Standby mode
Operating mode
Standby
mode
Standby
mode
Operating mode
UVLO
UVLO
Operating mode
EN
Standby mode
UVLO
Fig.20 Soft start, Shutdown, UVLO timing chart
・Short-current protection circuit with time delay function
Turns OFF the output to protect the IC from breakdown when the incorporated current limiter is activated continuously for
the fixed time(TLATCH) or more. The output thus held tuned OFF may be recovered by restarting EN or by re-unlocking
UVLO.
EN
Output OFF
latch
Output Short circuit
Threshold Voltage
VOUT
IL Limit
IL
t1<TLATCH
Standby
mode
t2=TLATCH
Operating mode
EN
Standby
mode
Timer latch
Operating mode
EN
Fig.21 Short-current protection circuit with time delay timing chart
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Datasheet
BD8961NV
Information on Advantages
Advantage 1:Offers fast transient response with current mode control system.
Conventional product (Load response IO=0.1A→0.6A)
BD8961NV (Load response IO=1A→2A)
VOUT
VOUT
100mV
160mV
IOUT
IOUT
Voltage drop due to sudden change in load was reduced by about 50%.
Fig.22 Comparison of transient response
Advantage 2: Offers high efficiency with synchronous rectifier
・For heavier load:
Utilizes the synchronous rectifying mode and the low on-resistance MOS FETs
incorporated as power transistor.
100
90
EFFICIENCY:η [%]
80
ON resistance of P-channel MOS FET : 200mΩ(Typ.)
ON resistance of N-channel MOS FET : 160mΩ(Typ.)
70
60
50
40
30
VCC=5V
20
10
0
10
100
1000
10000
OUTPUT CURRENT:IOUT[mA]
Fig.23 Efficiency
Advantage 3:・Supplied in smaller package due to small-sized power MOS FET incorporated.
・Output capacitor Co required for current mode control: 22μF ceramic capacitor
・Inductance L required for the operating frequency of 1 MHz: 2.2μH inductor
Reduces a mounting area required.
VCC
15mm
Cin
CIN
DC/DC
Convertor
Controller
RITH
RITH
L
VOUT
L
10mm
CITH
Co
CO
CITH
Fig.24 Example application
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Datasheet
BD8961NV
Switching Regulator Efficiency
Efficiency ŋ may be expressed by the equation shown below:
POUT
η= VOUT×IOUT ×100[%]= POUT ×100[%]=
Vin×Iin
Pin
POUT+PDα
×100[%]
Efficiency may be improved by reducing the switching regulator power dissipation factors PDα as follows:
Dissipation factors:
2
1) ON resistance dissipation of inductor and FET:PD(I R)
2) Gate charge/discharge dissipation:PD(Gate)
3) Switching dissipation:PD(SW)
4) ESR dissipation of capacitor:PD(ESR)
5) Operating current dissipation of IC:PD(IC)
2
2
1)PD(I R)=IOUT ×(RCOIL+RON) (RCOIL[Ω]:DC resistance of inductor, RON[Ω]:ON resistance of FET, IOUT[A]:Output
current.)
2)PD(Gate)=Cgs×f×V (Cgs[F]:Gate capacitance of FET, f[Hz]:Switching frequency, V[V]:Gate driving voltage of FET)
2
Vin ×CRSS×IOUT×f
(CRSS[F]:Reverse transfer capacitance of FET, IDRIVE[A]:Peak current of gate.)
3)PD(SW)=
IDRIVE
2
4)PD(ESR)=IRMS ×ESR (IRMS[A]:Ripple current of capacitor, ESR[Ω]:Equivalent series resistance.)
5)PD(IC)=Vin×ICC (ICC[A]:Circuit current.)
Consideration on Permissible Dissipation and Heat Generation
As this IC functions with high efficiency without significant heat generation in most applications, no special consideration is
needed on permissible dissipation or heat generation. In case of extreme conditions, however, including lower input
voltage, higher output voltage, heavier load, and/or higher temperature, the permissible dissipation and/or heat generation
must be carefully considered.
For dissipation, only conduction losses due to DC resistance of inductor and ON resistance of FET are considered.
Because the conduction losses are considered to play the leading role among other dissipation mentioned above including
gate charge/discharge dissipation and switching dissipation.
①3.9W
Power dissipation:Pd [W]
4.0
①for SON008V5060
JEDEC 4 layer board 76.2×114.3×1.6mm
θj-a=32.1℃/W
②for SON008V5060
ROHM standard 1 layer board 70×70×1.6mm
θj-a=138.9℃/W
③ IC only
θj-a=195.3℃/W
3.0
2
P=IOUT ×RON
RON=D×RONP+(1-D)RONN
D:ON duty (=VOUT/VCC)
RCOIL:DC resistance of coil
RONP:ON resistance of P-channel MOS FET
RONN:ON resistance of N-channel MOS FET
IOUT:Output current
2.0
1.0
②0.90W
③0.64W
0
0
25
50
75
100 105 125
150
Ambient temperature:Ta [℃]
Fig.25 Thermal derating curve
(SON008V5060)
If VCC=5V, VOUT=3.3V, RONP=0.2Ω, RONN=0.16Ω
IOUT=2A, for example,
D=VOUT/VCC=3.3/5.0=0.66
RON=0.66×0.20+(1-0.66)×0.16
=0.132+0.0544
=0.1864[Ω]
2
P=2 ×0.1864=0.7456W]
As RONP is greater than RONN in this IC, the dissipation increases as the ON duty becomes greater.
With the consideration on the dissipation as above, thermal design must be carried out with sufficient margin allowed.
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Datasheet
BD8961NV
Selection of Components Externally Connected
1. Selection of inductor (L)
The inductance significantly depends on output ripple current.
As seen in the equation (1), the ripple current decreases as
the inductor and/or switching frequency increases.
IL
ΔIL
VCC
ΔIL=
IL
(VCC-VOUT)×VOUT
[A]・・・(1)
L×VCC×f
Appropriate ripple current at output should be 20% more or less of
the maximum output current.
VOUT
L
ΔIL=0.3×IOUTmax. [A]・・・(2)
Co
(VCC-VOUT)×VOUT
L=
[H]・・・(3)
ΔIL×VCC×f
(ΔIL: Output ripple current, and f: Switching frequency)
Fig.26 Output ripple current
* Current exceeding the current rating of the inductor results in magnetic saturation of the inductor, which decreases efficiency.
The inductor must be selected allowing sufficient margin with which the peak current may not exceed its current rating.
If VCC=5V, VOUT=3.3V, f=1MHz, ΔIL=0.3×2A=0.6A, for example,(BD8961NV)
(5.0-3.3)×3.3
0.6×5.0×1M
L=
=1.87μ → 2.2[μH]
*Select the inductor of low resistance component (such as DCR and ACR) to minimize dissipation in the inductor for
better efficiency.
2. Selection of output capacitor (CO)
VCC
Output capacitor should be selected with the consideration on the stability
region and the equivalent series resistance required to smooth ripple voltage.
Output ripple voltage is determined by the equation (4):
VOUT
L
ESR
ΔVOUT=ΔIL×ESR [V]・・・(4)
Co
(ΔIL: Output ripple current, ESR: Equivalent series resistance of output capacitor)
*Rating of the capacitor should be determined allowing sufficient margin
against output voltage. Less ESR allows reduction in output ripple voltage.
22µF to 100µF ceramic capacitor is recommended.
Fig.27 Output capacitor
3. Selection of input capacitor (Cin)
VCC
Input capacitor to select must be a low ESR capacitor of the capacitance
sufficient to cope with high ripple current to prevent high transient voltage. The
ripple current IRMS is given by the equation (5):
Cin
√VOUT(VCC-VOUT)
VOUT
L
Co
IRMS=IOUT×
VCC
[A]・・・(5)
< Worst case > IRMS(max.)
IOUT
When Vcc is twice the VOUT, IRMS=
Fig.28 Input capacitor
2
If VCC=5.0V, VOUT=3.3V, and IOUTmax.=2A, (BD8961NV)
√3.3(5.0-3.3)
=0.947[ARMS]
35.0
.
3
A low ESR 22μF/10V ceramic capacitor is recommended to reduce ESR dissipation of input capacitor for better efficiency.
IRMS=2×
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Datasheet
BD8961NV
4. Determination of RITH, CITH that works as a phase compensator
As the Current Mode Control is designed to limit a inductor current, a pole (phase lag) appears in the low frequency area
due to a CR filter consisting of a output capacitor and a load resistance, while a zero (phase lead) appears in the high
frequency area due to the output capacitor and its ESR. So, the phases are easily compensated by adding a zero to the
power amplifier output with C and R as described below to cancel a pole at the power amplifier.
fp(Min.)
1
2π×RO×CO
1
fz(ESR)=
2π×ESR×CO
A
Gain
[dB]
fp=
fp(Max.)
0
fz(ESR)
IOUTMin.
Phase
[deg]
IOUTMax.
Pole at power amplifier
When the output current decreases, the load resistance Ro
increases and the pole frequency lowers.
0
-90
Fig.29 Open loop gain characteristics
fp(Min.)=
1
2π×ROMax.×CO
[Hz]←with lighter load
fp(Max.)=
1
2π×ROMin.×CO
[Hz] ←with heavier load
A
fz(Amp.)
Zero at power amplifier
Increasing capacitance of the output capacitor lowers the pole
frequency while the zero frequency does not change.
(This is because when the capacitance is doubled, the capacitor
ESR reduces to half.)
Gain
[dB]
0
0
Phase
[deg]
-90
fz(Amp.)=
1
2π×RITH×CITH
Fig.30 Error amp phase compensation characteristics
VCC
Cin
EN
VOUT
L
VCC,PVCC
VOUT
ITH
VOUT
SW
ESR
GND,PGND
RO
CO
RITH
CITH
Fig.31 Typical application
Stable feedback loop may be achieved by canceling the pole fp (Min.) produced by the output capacitor and the load
resistance with CR zero correction by the error amplifier.
fz(Amp.)= fp(Min.)
1
2π×RITH×CITH
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2π×ROMax.×CO
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Datasheet
BD8961NV
BD8961NV Cautions on PC Board layout
VCC
1
2
3
RITH
③
CITH
EN 8
VOUT
VCC
PVCC
ITH
SW
4
7
①
L
6
VOUT
5
GND
EN
PGND
CIN
Co
②
GND
Fig.32 Layout diagram
①
②
③
※
For the sections drawn with heavy line, use thick conductor pattern as short as possible.
Lay out the input ceramic capacitor CIN closer to the pins PVCC and PGND, and the output capacitor Co closer to
the pin PGND.
Lay out CITH and RITH between the pins ITH and GND as near as possible with least necessary wiring.
SON008V5060 (BD8961NV) has thermal FIN on the reverse of the package.
The package thermal performance may be enhanced by bonding the FIN to GND plane which take a large area of PCB.
Recommended Components Lists on Above Application
Symbol
Value
Manufacturer
Series
Coil
2.2uH
TDK
LTF5022-2R2N3R2
CIN
Ceramic capacitor
22uF
Kyocera
CM32X5R226M10A
CO
Ceramic capacitor
22uF
Kyocera
CM316B226M06A
CITH
Ceramic capacitor
680pF
murata
RITH
Resistance
12kΩ
Rohm
L
Part
GRM18 Serise
MCR03Serise
*The parts list presented above is an example of recommended parts. Although the parts are sound, actual circuit characteristics should be checked on your
application carefully before use. Be sure to allow sufficient margins to accommodate variations between external devices and this IC when employing the
depicted circuit with other circuit constants modified. Both static and transient characteristics should be considered in establishing these margins. When
switching noise is substantial and may impact the system, a low pass filter should be inserted between the VCC and PVCC pins, and a schottky barrier
diode established between the SW and PGND pins.
I/O equivalence circuit
・EN pin
PVCC
・SW pin
PVCC
PVCC
EN
SW
・ITH pin
・VOUT pin
VCC
VCC
10kΩ
ITH
VOUT
Fig.33 I/O equivalence circuit
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Datasheet
BD8961NV
●Operational Notes
1. Absolute Maximum Ratings
While utmost care is taken to quality control of this product, any application that may exceed some of the absolute
maximum ratings including the voltage applied and the operating temperature range may result in breakage. If broken,
short-mode or open-mode may not be identified. So if it is expected to encounter with special mode that may exceed the
absolute maximum ratings, it is requested to take necessary safety measures physically including insertion of fuses.
2. Electrical potential at GND
GND must be designed to have the lowest electrical potential In any operating conditions.
3. Short-circuiting between terminals, and mismounting
When mounting to pc board, care must be taken to avoid mistake in its orientation and alignment. Failure to do so may
result in IC breakdown. Short-circuiting due to foreign matters entered between output terminals, or between output and
power supply or GND may also cause breakdown.
4.Operation in Strong electromagnetic field
Be noted that using the IC in the strong electromagnetic radiation can cause operation failures.
5. Thermal shutdown protection circuit
Thermal shutdown protection circuit is the circuit designed to isolate the IC from thermal runaway, and not intended to
protect and guarantee the IC. So, the IC the thermal shutdown protection circuit of which is once activated should not
be used thereafter for any operation originally intended.
6. Inspection with the IC set to a pc board
If a capacitor must be connected to the pin of lower impedance during inspection with the IC set to a pc board, the
capacitor must be discharged after each process to avoid stress to the IC. For electrostatic protection, provide proper
grounding to assembling processes with special care taken in handling and storage. When connecting to jigs in the
inspection process, be sure to turn OFF the power supply before it is connected and removed.
7. Input to IC terminals
+
This is a monolithic IC with P isolation between P-substrate and each element as illustrated below. This P-layer and
the N-layer of each element form a P-N junction, and various parasitic element are formed.
If a resistor is joined to a transistor terminal as shown in Fig34.
○P-N junction works as a parasitic diode if the following relationship is satisfied; GND>Terminal A (at resistor side), or
GND>Terminal B (at transistor side); and
○if GND>Terminal B (at NPN transistor side),
a parasitic NPN transistor is activated by N-layer of other element adjacent to the above-mentioned parasitic diode.
The structure of the IC inevitably forms parasitic elements, the activation of which may cause interference among circuits,
and/or malfunctions contributing to breakdown. It is therefore requested to take care not to use the device in such
manner that the voltage lower than GND (at P-substrate) may be applied to the input terminal, which may result in
activation of parasitic elements.
Resistor
Transistor (NPN)
Pin A
Pin B
C
B
E
Pin A
N
N
P
+
N
P
P
+
N
P substrate
Parasitic element
GND
Pin B
Parasiti
c
elemen
t
P
+
B
N
P
P
+
N
C
E
Parasitic
element
P substrate
GND
Parasitic
element
Fig.34 Simplified structure
of monorisic IC
GND
GND
Other adjacent elements
8. Ground wiring pattern
If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND
pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that
resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of the
small-signal GND. Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well.
9 . Selection of inductor
It is recommended to use an inductor with a series resistance element (DCR) 0.1Ω or less. Note that use of a high DCR
inductor will cause an inductor loss, resulting in decreased output voltage. Should this condition continue for a specified
period (soft start time + timer latch time), output short circuit protection will be activated and output will be latched OFF.
When using an inductor over 0.1Ω, be careful to ensure adequate margins for variation between external devices and this
IC, including transient as well as static characteristics. Furthermore, in any case, it is recommended to start up the output
with EN after supply voltage is within operation range.
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.
www.rohm.com
© ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
15/16
TSZ02201-0J3J0AJ00020-1-2
02.MAR.2012 Rev.001
Datasheet
BD8961NV
●Ordering Information
B
D
8
9
6
1
N
V
-
Package
E2
Packaging and forming specification
NV: SON008V5060
E2: Embossed tape and reel
●Physical Dimension Tape and Reel information
●Marking Diagram
SON008V5060 (TOP VIEW)
Part Number Marking
D 8 9 6 1
LOT Number
1PIN MARK
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© ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
16/16
TSZ02201-0J3J0AJ00020-1-2
02.MAR.2012 Rev.001
Datasheet
Notice
●Precaution for circuit design
1) The products are designed and produced for application in ordinary electronic equipment (AV equipment, OA
equipment, telecommunication equipment, home appliances, amusement equipment, etc.). If the products are to be
used in devices requiring extremely high reliability (medical equipment, transport equipment, aircraft/spacecraft,
nuclear power controllers, fuel controllers, car equipment including car accessories, safety devices, etc.) and whose
malfunction or operational error may endanger human life and sufficient fail-safe measures, please consult with the
ROHM sales staff in advance. If product malfunctions may result in serious damage, including that to human life,
sufficient fail-safe measures must be taken, including the following:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits in the case of single-circuit failure
2)
The products are designed for use in a standard environment and not in any special environments. Application of the
products in a special environment can deteriorate product performance. Accordingly, verification and confirmation of
product performance, prior to use, is recommended if used under the following conditions:
[a] Use in various types of liquid, including water, oils, chemicals, and organic solvents
[b] Use outdoors where the products are exposed to direct sunlight, or in dusty places
[c] Use in places where the products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2,
and NO2
[d] Use in places where the products are exposed to static electricity or electromagnetic waves
[e] Use in proximity to heat-producing components, plastic cords, or other flammable items
[f] Use involving sealing or coating the products with resin or other coating materials
[g] Use involving unclean solder or use of water or water-soluble cleaning agents for cleaning after soldering
[h] Use of the products in places subject to dew condensation
3)
The products are not radiation resistant.
4)
Verification and confirmation of performance characteristics of products, after on-board mounting, is advised.
5)
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.
6)
De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta).
When used in sealed area, confirm the actual ambient temperature.
7)
Confirm that operation temperature is within the specified range described in product specification.
8)
Failure induced under deviant condition from what defined in the product specification cannot be guaranteed.
●Precaution for Mounting / Circuit board design
1) When a highly active halogenous (chlorine, bromine, etc.) flux is used, the remainder 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
Company in advance.
Regarding Precaution for Mounting / Circuit board design, please specially refer to ROHM Mounting specification
●Precautions Regarding Application Examples and External Circuits
1) If change is made to the constant of an external circuit, allow a sufficient margin due to variations of the characteristics
of the products and external components, including transient characteristics, as well as static characteristics.
2)
The application examples, their constants, and other types of information contained herein are applicable only when
the products are used in accordance with standard methods. Therefore, if mass production is intended, sufficient
consideration to external conditions must be made.
Notice - Rev.001
Datasheet
●Precaution for Electrostatic
This product is Electrostatic sensitive product, which may be damaged due to Electrostatic discharge. Please take proper
caution during manufacturing and storing so that voltage exceeding Product maximum rating won't 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 following places:
[a] Where the products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] Where the temperature or humidity exceeds those recommended by the Company
[c] Storage in direct sunshine or condensation
[d] Storage in 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 recommended storage time period .
3)
Store / transport cartons in the correct direction, which is indicated on a carton as 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 dry bag.
●Precaution for product label
QR code printed on ROHM product label is only for internal use, and please do not use at customer site. It might contain a
internal part number that is inconsistent with an product part number.
●Precaution for disposition
When disposing products please dispose them properly with a industry waste company.
●Precaution for Foreign exchange and Foreign trade act
Since concerned goods might be fallen under controlled goods prescribed by Foreign exchange and Foreign trade act,
please consult with ROHM in case of export.
●Prohibitions Regarding Industrial Property
1) Information and data on products, including application examples, contained in these specifications are simply for
reference; the Company does not guarantee any industrial property rights, intellectual property rights, or any other
rights of a third party regarding this information or data. Accordingly, the Company does not bear any responsibility for:
[a] infringement of the intellectual property rights of a third party
[b] any problems incurred by the use of the products listed herein.
2)
The Company prohibits the purchaser of its products to exercise or use the intellectual property rights, industrial
property rights, or any other rights that either belong to or are controlled by the Company, other than the right to use,
sell, or dispose of the products.
Notice - Rev.001