BD8964FVM-TR [ROHM]
暂无描述;4.0V to 5.5V, 1.2A 1ch
Synchronous Buck Converter Integrated FET
BD8964FVM
●General Description
ROHM’s high efficiency step-down switching
●Key Specifications
Input voltage range:
Output voltage range:
Output current:
4.0V to 5.5V
1.0V to 1.8V
1.2A (Max.)
1.0MHz(Typ.)
350mΩ(Typ.)
250mΩ(Typ.)
regulator BD8964FVM is a power supply designed
to produce a low voltage including 1 volts from 5/3.3
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.
Switching frequency:
Pch FET ON resistance:
Nch FET ON resistance:
Standby current:
0μA (Typ..)
Operating temperature range:
-25℃ to +85℃
●Features
Offers fast transient response with current mode
PWM control system.
●Packages
Offers highly efficiency for all load range with
synchronous rectifier (Nch/Pch FET)
Incorporates soft-start function.
Incorporates thermal protection and ULVO
functions.
MSOP8
2.90mm x 4.00mm x 0.83mm
●Application
Power supply for LSI including DSP, Micro computer
and ASIC
Incorporates short-current protection circuit with
time delay function.
Incorporates shutdown function
●Typical Application Circuit
Cin
L
VCC
VCC,PVCC
EN
SW
VOUT
VOUT
VOUT
ITH
ESR
CO
RO
GND,PGND
RITH
CITH
Fig.1 Typical application
○Product structure:Silicon monolithic integrated circuit ○This product is not designed protection against radioactive rays.
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BD8964FVM
●Pin Configuration
(TOP VIEW)
1
2
3
4
8
7
6
5
VCC
ADJ
ITH
PVCC
SW
EN
GND
PGND
MSOP8
Fig.2 Pin configuration
●Pin Description
Pin No.
Pin name
ADJ
PIN function
1
2
3
4
5
6
7
8
Output voltage detect pin
ITH
GmAmp output pin/Connected phase compensation capacitor
Enable pin(Active High)
EN
GND
PGND
SW
Ground
Nch FET source pin
Pch/Nch FET drain output pin
Pch FET source pin
PVCC
VCC
VCC power supply input pin
●Block Diagram
Fig.3 Block Diagram
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BD8964FVM
●Absolute Maximum Ratings
Parameter
Symbol
VCC
Limits
-0.3 to +7 *1
-0.3 to +7 *1
-0.3 to +7
-0.3 to +7
387.5*2
Unit
V
VCC Voltage
PVCC Voltage
PVCC
VEN
V
EN Voltage
V
SW,ITH Voltage
VSW,VITH
Pd1
V
Power Dissipation 1
Power Dissipation 2
Operating temperature range
Storage temperature range
mW
mW
℃
℃
℃
Pd2
587.4*3
Topr
-25 to +85
-55 to +150
+150
Tstg
Maximum junction temperature
Tjmax
*1 Pd should not be exceeded.
*2 Derating in done 3.1mW/℃ for temperatures above Ta=25℃.
*3 Derating in done 4.7mW/℃ for temperatures above Ta=25℃, Mounted on 70mm×70mm×1.6mm Glass Epoxy PCB.
●Operating Ratings(Ta=25℃)
Limits
Unit
Parameter
Symbol
Min.
4.0
4.0
0
Typ.
Max.
5.5
*4
VCC Voltage
VCC
5.0
V
V
V
V
A
*4
PVCC Voltage
PVCC
5.0
5.5
EN Voltage
VEN
VOUT
Isw *4
-
-
-
VCC
1.8
Output voltage Setting Range
SW average output current
1.0
-
1.2
*4
Pd should not be exceeded.
●Electrical Characteristics
◎ (Ta=25℃, VCC=5V, EN=VCC, R1=20kΩ, R2=10kΩ unless otherwise specified.)
Parameter
Standby current
Symbol
ISTB
Min.
-
Typ.
0
Max.
10
450
0.8
-
Unit
μA
μA
V
Conditions
EN=GND
Bias current
ICC
-
250
GND
VCC
1
EN Low voltage
VENL
VENH
IEN
-
Standby mode
Active mode
VEN=5V
EN High voltage
2.0
-
V
EN input current
Oscillation frequency
Pch FET ON resistance
Nch FET ON resistance
ADJ voltage
10
1.2
600
500
0.82
-
μA
MHz
mΩ
mΩ
V
FOSC
RONP
RONN
VADJ
ITHSI
0.8
-
1
350
250
0.80
20
PVCC=5V
PVCC=5V
-
0.78
10
10
3.6
3.65
0.5
1
ITH SInk current
μA
μA
V
VADJ=H
ITH Source Current
UVLO threshold voltage
UVLO release voltage
Soft start time
ITHSO
VUVLO1
VUVLO2
TSS
20
-
VADJ=L
3.8
3.90
1
4.0
4.2
2
VCC=4→0V
VCC=0→4V
VADJ=H
V
ms
ms
Timer latch time
TLATCH
2
3
SCP/TSD operated
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BD8964FVM
●Typical Performance Curves
Fig.5 Ven-Vout
Fig.4 Vcc-Vout
0
Fig.7 Ta-VOUT
Fig.6 Iout-Vout
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BD8964FVM
Fig.9 Ta-FOSC
Fig.8 Efficiency
Fig.10 Ta-RONN, RONP
Fig.11 Ta-VEN
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Fig.12 Ta-ICC
Fig.13 Vcc-Fosc
Fig.14 Soft start waveform
Fig.15 SW waveform
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BD8964FVM
Fig. 16 Transient response
Fig.17 Transient response
Io=100→600mA(10μs)
Io=600→100mA(10μs)
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BD8964FVM
●Application Information
Operation
BD8964FVM 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 IL increases. The current comparator (Current Comp)
receives two signals, a current feedback control signal (SENSE: Voltage converted from IL) 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
VOUT
RESET
R
S
Q
IL
Level
Shift
FB
SET
Driver
Logic
VOUT
Gm Amp.
SW
Load
OSC
ITH
Fig.18 Diagram of current mode PWM control
PVCC
Current
Comp
SENSE
FB
SET
GND
GND
RESET
SW
GND
IL(AVE)
IL
VOUT
VOUT(AVE)
Fig.19 PWM switching timing chart
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BD8964FVM
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. And the hysteresis width
of 300mV (Typ.) is provided to prevent output chattering.
Hysteresis 100mV
VCC
EN
VOUT
Tss
Tss
Tss
Soft start
Standby
mode
Standby
mode
Standby mode
Operating mode
Operating mode
Operating mode
Standby mode
UVLO
EN
UVLO
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
at least 1 ms. The output thus held tuned OFF may be recovered by restarting EN or by re-unlocking UVLO.
EN
Output OFF
latch
VOUT
Limit
IL
1msec
Standby
mode
Standby
mode
Operating mode
Operating mode
EN
Timer latch
EN
Fig.21 Short-current protection circuit with time delay timing chart
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Datasheet
BD8964FVM
Information on Advantages
Advantage 1:Offers fast transient response with current mode control system.
BD8964FVM (Load response IO=0.1A→0.6A)
Conventional product (Load response IO=0.1A→0.6A)
VOUT
VOUT
58mV
110mV
IOUT
IOUT
Voltage drop due to sudden change in load was reduced
Fig.22 Comparison of transient response
100
Advantage 2: Offers high efficiency with synchronous rectifier
【VOUT=1.5V】
90
80
70
60
50
40
30
20
10
0
・For heavier load:
Utilizes the synchronous rectifying mode and the low on-resistance
MOS FETs incorporated as power transistor.
VCC=5V
Ta=25℃
ON resistance of P-channel MOS FET : 350mΩ(Typ.)
ON resistance of N-channel MOS FET : 250mΩ(Typ.)
1
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: 10μF ceramic capacitor
・Inductance L required for the operating frequency of 1 MHz: 4.7μH inductor
Reduces a mounting area required.
VCC
15mm
CIN
Cin
RITH
CITH
L
DC/DC
Convertor
Controller
L
VOUT
10mm
RITH
CITH
Co
CO
Fig.24 Example application
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BD8964FVM
Switching Regulator Efficiency
Efficiency ŋ may be expressed by the equation shown below:
POUT
VOUT×IOUT
POUT
×100[%]=
×100[%]
η=
×100[%]=
Vin×Iin
POUT+PDα
Pin
Efficiency may be improved by reducing the switching regulator power dissipation factors PDα as follows:
Dissipation factors:
1) ON resistance dissipation of inductor and FET:PD(I2R)
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
1)PD(I2R)=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)
Vin2×CRSS×IOUT×f
3)PD(SW)=
(CRSS[F]:Reverse transfer capacitance of FET, IDRIVE[A]:Peak current of gate.)
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.
2
P=IOUT ×(RCOIL+RON)
RON=D×RONP+(1-D)RONN
1000
①using an IC alone
D:ON duty (=VOUT/VCC)
RCOIL:DC resistance of coil
θj-a=322.6℃/W
800
②mounted on glass epoxy PCB
RONP:ON resistance of P-channel MOS FET
θj-a=212.8℃/W
①587.4mW
RONN:ON resistance of N-channel MOS FET
IOUT:Output current
600
②387.5mW
If VCC=5V, VOUT=1.5V, RCOIL=0.15Ω, RONP=0.35Ω, RONN=0.25Ω
400
200
0
IOUT=0.8A, for example,
D=VOUT/VCC=1.5/5=0.3
RON=0.3×0.35+(1-0.3)×0.25
=0.105+0.175
=0.28[Ω]
0
25
50
75 85 100
125
150
P
=0.82×(0.15+0.28)
≒275.2[mW]
Fig. 25
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
BD8964FVM
Selection of Components Externally Connected
1. Selection of inductor (L)
IL
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.
ΔIL
VCC
(VCC-VOUT)×VOUT
ΔIL=
[A]・・・(1)
L×VCC×f
IL
Appropriate ripple current at output should be 30% more or less of the
maximum output current.
VOUT
ΔIL=0.3×IOUTmax. [A]・・・(2)
L
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=1.5V, f=1MHz, ΔIL=0.3×0.8A=0.24A, for example,
(5-1.5)×1.5
L=
=4.375μ → 4.7[μH]
0.24×5×1M
*Select the inductor of low resistance component (such as DCR andACR) 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
ΔVOUT=ΔIL×ESR [V]・・・(4)
ESR
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.
Fig.27 Output capacitor
As the output rise time must be designed to fall within the soft-start time, the capacitance of output capacitor should be
determined with consideration on the requirements of equation (5):
TSS×(Ilimit-IOUT)
VOUT
Tss: Soft-start time
Ilimit: Over current detection level, 2A(Typ)
Co≦
・・・(5)
In case of BD8964FVM, for instance, and if VOUT=1.5V, IOUT=0.8A, and TSS=1ms,
1m×(2-0.8)
Co≦
≒800[μF]
1.5
Inappropriate capacitance may cause problem in startup. A 10 μF to 100 μF ceramic capacitor is recommended.
3. Selection of input capacitor (Cin)
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):
VCC
Cin
√
VOUT(VCC-VOUT)
IRMS=IOUT×
[A]・・・(5)
VOUT
VCC
L
Co
< Worst case > IRMS(max.)
IOUT
2
When Vcc is twice the VOUT, IRMS=
If VCC=5.0V, VOUT=1.5V, and IOUTmax.=0.8A
Fig.28 Input capacitor
√
5(5-1.5)
IRMS=0.8×
=0.67[ARMS]
5
A low ESR 10μF/10V ceramic capacitor is recommended to reduce ESR dissipation of input capacitor for better efficiency.
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BD8964FVM
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.)
A
1
fp=
fp(Max.)
2π×RO×CO
Gain
[dB]
0
1
fz(ESR)=
fz(ESR)
2π×ESR×CO
IOUTMin.
IOUTMax.
Pole at power amplifier
0
When the output current decreases, the load resistance Ro
increases and the pole frequency lowers.
Phase
[deg]
-90
1
fp(Min.)=
[Hz]←with lighter load
2π×ROMax.×CO
Fig.29 Open loop gain characteristics
1
fp(Max.)=
[Hz] ←with heavier load
2π×ROMin.×CO
A
fz(Amp.)
Gain
[dB]
Zero at power amplifier
0
0
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.)
Phase
[deg]
-90
1
fz(Amp.)=
2π×RITH×CITH
Fig.30 Error amp phase compensation characteristics
Cin
L
VCC
VCC,PVCC
EN
SW
VOUT
VOUT
VOUT
ITH
ESR
CO
RO
GND,PGND
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
1
=
2π×RITH×CITH
2π×ROMax.×CO
5. Determination of output voltage
The output voltage VOUT is determined by the equation (7):
VOUT=(R2/R1+1)×VADJ・・・(7) VADJ: Voltage at ADJ terminal (0.8V Typ.)
With R1 and R2 adjusted, the output voltage may be determined as required.
(Adjustable output voltage range: 1.0V to 1.8V)
Use 1 kΩ to 100 kΩ resistor for R1. If a resistor of the resistance higher than
100 kΩ is used, check the assembled set carefully for ripple voltage etc.
4.7µH
6
1
Output
SW
10µF
R2
R1
ADJ
Fig.32 Determination of output voltage
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BD8964FVM
BD8964FVM Cautions on PC Board Layout
VCC
EN
1
2
8
7
EN
ADJ
VCC
ITH
PVCC
SW
L
①
3
6
5
VOUT
RITH
4
CIN
Co
③
GND
PGND
②
CITH
GND
Fig.33 Layout diagram
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.
①
②
③
Lay out CITH and RITH between the pins ITH and GND as near as possible with least necessary wiring.
Recommended Components Lists on Above Application
Symbol
Part
Value
Manufacturer
Sumida
TDK
Kyocera
Kyocera
murata
ROHM
Series
CMD6D11B
VLF5014AT-4R7M1R1
CM316X5R106K10A
CM316X5R106K10A
GRM18series
L
Coil
4.7μH
CIN
CO
Ceramic capacitor
Ceramic capacitor
Ceramic capacitor
10μF
10μF
1000pF
CITH
VOUT=1.0V
4.3kΩ
6.8kΩ
9.1kΩ
12kΩ
MCR10 4301
MCR10 6801
MCR10 9101
MCR10 1202
VOUT=1.2V
VOUT=1.5V
VOUT=1.8V
ROHM
ROHM
ROHM
RITH
Resistance
* 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
PVCC
PVCC
PVCC
・EN pin
・SW pin
EN
SW
・ADJ pin
・ITH pin
VCC
VCC
10kΩ
ITH
ADJ
Fig.34 I/O equivalence circuit
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Datasheet
BD8964FVM
●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 Fig 35.
○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.
Fig.35 Simplified structure of monorisic IC
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
TSZ02201-0J3J0AJ00050-1-2
©
ROHM Co., Ltd. All rights reserved.
15/16
TSZ22111・15・001
02.MAR.2012 Rev.001
Datasheet
BD8964FVM
●Ordering Information
B D 8
9
6 4
F
V
M -
T R
Package
Packaging and forming specification
TR: Embossed tape and reel
FVM:MSOP8
●Physical Dimension Tape and Reel information
●Marking Diagram
MSOP8(TOP VIEW)
Part Number Marking
D
8
9
LOT Number
6
4
1PIN MARK
www.rohm.com
ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
TSZ02201-0J3J0AJ00050-1-2
02.MAR.2012 Rev.001
©
16/16
Daattaasshheeeett
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
Daattaasshheeeett
●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
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