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Datasheet
4.2V to 18V, 2A 1ch
Synchronous Buck Converter with
Integrated FET
BD9328EFJ
General Description
Key Specifications
The BD9328EFJ is a synchronous step-down
switching regulator with built-in two low-resistance
N-Channel MOSFETs. This IC can supply continuous
output current of 2A over a wide input range, and
provides not only fast transient response, but also
easy phase compensation because of current mode
control.








Input Voltage Range:
4.2V to 18V
Output Voltage Range:
0.9V to (VIN x 0.7)V
Output Current:
2A (Max)
Switching Frequency:
380kHz(Typ)
Hi-Side FET ON-Resistance:
0.15Ω(Typ)
Lo-Side FET ON-Resistance:
0.13Ω(Typ)
Standby Current:
15μA (Typ)
Operating Temperature Range:
-40°C to +85°C
Features
Uses Low ESR Output Ceramic Capacitors
Low Standby Current
380 kHz Fixed Operating Frequency
Feedback Voltage
 0.9V ± 1.5%(Ta=25°C)
 0.9V ± 2.0%(Ta=-25°C to +85°C)
 Under Voltage Protection
 Thermal Shutdown
 Over Current Protection




W (Typ)
Package
D (Typ)
H (Max)
Applications
Distributed Power Systems
Pre-Regulator for Linear Regulators
HTSOP-J8
4.90mm x 6.00mm x 1.00mm
Typical Application Circuit
C_PC
3300pF
R_PC
7.5kΩ
R_DW
10kΩ
R_UP
27kΩ
FB
COMP
EN
SS
C_SS
0.1μF
Thermal Pad
GND
SW
BST
VIN
(to be shorted to GND)
VIN = 12V
L
VOUT = 3.3V
10µH
C_BS
0.1μF
R_BS
22Ω
C_VC1
10μF
C_CO1
20μF
R_BS protect from VIN-BST short destruction.
Figure 1. Typical Application Circuit
〇Product structure : Silicon monolithic integrated circuit
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Datasheet
BD9328EFJ
Pin Configuration
Block Diagram
(TOP VIEW)
SS
EN
COMP
FB
BST
VIN
SW
GND
VIN
Figure 2. Pin Configuration
Figure 3. Block Diagram
Pin Description
Pin No.
Pin Name
1
BST
High-side gate drive boost input
2
VIN
Power input
3
SW
4
GND
Function
Power switching output
Ground
5
FB
6
COMP
7
EN
Enable input
8
SS
Soft start control input
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Feedback input
Compensation node
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Datasheet
BD9328EFJ
Absolute Maximum Ratings (Ta = 25°C)
Parameter
Symbol
Rating
Unit
Supply Voltage
VIN
20
V
Switch Voltage
VSW
20
V
Power Dissipation for HTSOP-J8
Pd
Package Thermal Resistance θja (Note 2)
θja
3.76
(Note 1)
W
29.27
°C /W
Package Thermal Resistance θjc (Note 2)
θjc
3.75
°C /W
Operating Temperature Range
Topr
-40 to +85
°C
Storage Temperature Range
Tstg
-55 to +150
°C
Tjmax
150
°C
VBST
VSW+7
V
EN Voltage
VEN
20
V
All Other Pins
VOTH
20
V
Maximum Junction Temperature
BST Voltage
(Note 1) Derating is done 30.08 mW/°C when operating above Ta ≥ 25°C (Mount on 4-layer 70.0mm x 70.0mm x 1.6mm board)
(Note 2) Mount on a 4-layer 50mm x 30mm x 1.6mm application board
Caution: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit
between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over
the absolute maximum ratings.
Recommended Operating Conditions (Ta= -40°C to +85°C)
Parameter
Symbol
Rating
Unit
Min
Typ
Max
12
18
V
Supply Voltage
VIN
4.2
SW Voltage
VSW
-0.5
-
+18
V
Output Current
ISW3
-
-
2
A
VRANGE
0.9
-
VIN x 0.7
V
Output Voltage Range
Electrical Characteristics (Unless otherwise specified VIN=12V Ta=25°C)
Parameter
Symbol
Limit
Unit
Conditions
Min
Typ
Max
IFB
-
0.02
2
µA
Feedback Voltage1
VFB1
0.886
0.900
0.914
V
Voltage Follower
Feedback Voltage2
VFB2
0.882
0.900
0.918
V
Ta=-25°C to +85°C
Hi-Side FET ON-Resistance
RONH
-
0.15
-
Ω
ISW= -0.8A
Lo-Side FET ON-Resistance
RONL
-
0.13
-
Ω
Hi/Lo-Side FET Leak Current
ILEAKN
-
0
10
µA
ISW= 0.8A
VIN= 18V,
VSW= 0V / 18V
Switch Current Limit
ILIMIT3
3
-
-
A
Maximum Duty Cycle
MDUTY
-
90
-
%
VFB= 0V
VEN= 12V
Error Amplifier Block
FB Input Bias Current
SW Block – SW
General
Enable Sink Current
IEN
90
180
270
µA
Enable Threshold Voltage
VEN
1.0
1.2
1.4
V
Under Voltage Lockout Threshold
VUVLO
3.5
3.75
4.0
V
Under Voltage Lockout Hysteresis
VHYS
-
0.3
-
V
ISS
5
10
15
µA
VSS= 0 V
CSS= 0.1 µF
Soft Start Current
VIN Rising
Soft Start Time
tSS
-
22
-
ms
Operating Frequency
fOSC
300
380
460
kHz
Circuit Current
ICC
-
1.2
3
mA
VFB= 1.5V, VEN= 12V
Standby Current
IQUI
-
15
27
µA
VEN= 0V
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BD9328EFJ
Typical Performance Curves
ICC (µA)
ICC (mA)
(Unless otherwise specified, VIN= 12V Ta= 25°C)
VIN (V)
VIN (V)
Figure 4. Circuit Current vs Input Voltage
(No Switching)
IFB (µA)
Figure 5. Standby Current vs Input Voltage
(Shutdown Mode)
VFB (V)
Temperature [°C]
Figure 6. Input Bias Current vs
Feedback Voltage
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Figure 7. Feedback Voltage vs Temperature
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BD9328EFJ
Typical Performance Curves - continued
390
385
RON [Ω]
fOSC (kHz)
FOSC
(kHz)
380
375
370
365
360
-4 0
Temperature [°C]
-2 0
0
20
40
60
80
T E M P ( °C[°C]
)
Temperature
Figure 8. Hi-Side, Low-Side FET
ON-Resistance vs Temperature
Figure 9. Operating Frequency vs Temperature
95
90
Soft Start Time [ms]
85
Efficiency
Efficiency[%]
80
75
70
65
60
55
50
0
500
1000
1500
2000
IOIo[mA]
[mA]
CSS [µF]
Figure 10. STEP-Down Efficiency vs IO
(VIN= 12V VOUT= 3.3V L=10µH)
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Figure 11. Soft Start Time vs
Soft Start Capacitor
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Typical Waveforms
VOUT
IOUT
Figure 13. Transient Response
(VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 0.2-1.0A )
Figure 12. Over Current Protection
(VOUT is shorted to GND)
Figure 14. Output Ripple Voltage
(VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 1.0A )
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Figure 15. Transient Response
(VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 0.2-2.0A)
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BD9328EFJ
Typical Waveforms - continued
tSS
Figure 16. Output Ripple Voltage
(VIN= 12V VOUT= 3.3V L= 10µH COUT =20µF IOUT= 2.0A )
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Figure 17. Start-Up Waveform
(VIN= 12V VOUT= 3.3V L= 10µH CSS= 0.1µF)
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BD9328EFJ
Application Information
1. Typical Application Circuit
C_PC
3300pF
R_PC
7.5kΩ
R_DW
10kΩ
R_UP
27kΩ
FB
COMP
EN
SS
C_SS
0.1μF
Thermal Pad
VIN = 12V
GND
SW
VIN
BST
(to be shorted to GND)
L
VOUT = 3.3V
10µH
C_CO1
20μF
C_BS
0.1μF
R_BS
22Ω
C_VC1
10μF
R_BS protect from VIN-BST short destruction.
Figure 18. Typical Application Circuit
Symbol
Maker
Part No
Input Capacitor
C_VC1
TDK
C3225JB1E106K
10µF/25V
Output Capacitor
C_CO1
TDK
C3216JB1C106M
10µF/16V
Inductor
L
TDK
SLF10165-100M3R8
10µH/3.8A
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BD9328EFJ
2. Block Operation
(1) VREG
This block generates a constant voltage for DC/DC boosting.
(2) VREF
This block generates an internal reference voltage of 5.1 V (Typ).
(3) TSD/UVLO
TSD (Thermal shutdown)/UVLO (Under Voltage Lockout) protection block.
The TSD circuit shuts down the IC at high temperature.
The UVLO circuit shuts down the IC when the VIN voltage is low.
(4) Error Amp Block (ERR)
This block compares the reference voltage and the feedback voltage from the output. The output voltage of this block,
which is connected to COMP pin, determines the switching duty cycle. At the time of startup, since the soft start is
operated by the SS pin voltage, the COMP pin voltage is limited to the SS pin voltage.
(5) Oscillator Block (OSC)
This block generates the oscillating frequency.
(6) SLOPE Block
This block generates the triangular waveform with the use of the clock created by OSC. The generated triangular
waveform is sent to the PWM comparator.
(7) PWM Block
The COMP pin voltage output of the error amp is compared to the SLOPE block's triangular waveform to determine
the switching duty. Since the switching duty cycle is limited by the maximum duty ratio which is determined internally,
100% duty cycle cannot be achieved.
(8) DRV Block
A DC/DC driver block that accepts signal from the PWM block to drive the power FETs.
(9) OCP Block
OCP (Over Current Protection) block. The current that flows through the FETs is detected, and OCP starts when it
reached 3.0A (min). After OCP detection, switching is turned off and the SS capacitor is discharged. OCP is not a
“latch type” but an “auto restart”.
(10) Soft Start Circuit
This circuit prevents output voltage overshoot or inrush current by making the output voltage rise gradually while
restricting the current at the time of startup.
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BD9328EFJ
3. Selecting Application Components
(1) Output LC Filter Constant Selection (Buck Converter)
The Output LC filter is required to supply constant current to the output load. A larger inductance value at this filter
results in less inductor ripple current (∆IL) and less output ripple voltage. However, inductors with large values tend to
have slower load transient-response, a larger physical size, a lower saturation current, and a higher series resistance.
A smaller value of inductance has almost opposite characteristics as above. So, choosing the Inductor ripple current
(∆IL) between 20% to 40% of the averaged inductor current (equivalent to the output load current) is a good
compromise.
∆IL /2
IOUTMAX + I
should not reach
the rated value level
IILL
VIN
VOUT
ILR
Inductor averaged current
L
COUT
t
Figure 19
Figure 20
Setting ∆IL = 30% x Averaged Inductor Current (2A) = 0.6 [A]
L  VOUT  VIN  VOUT  
1
VIN  f OSC  I L
 10 
H 
Where:
VIN= 12V, VOUT= 3.3V, fosc= 380 kHz,
fosc is the switching frequency
Also the inductor should have a higher saturation current than IOUTMAX + ∆IL / 2.
The output capacitor COUT affects the output ripple-voltage. Choose a high-value capacitor to achieve a smaller
ripple-voltage that is enough to meet the application requirement.
Output ripple voltage ∆VRPL is calculated using the following equation:

1
V RPL  I L   R ESR 
C
8

OUT  f OSC





V 
where:
RESR is the parasitic series resistance of the output capacitor.
Setting COUT = 20µF, RESR = 10mΩ
VRPL  0.6  (10 m  1 /(8  20   380k ))  15.8mV
(2) Loop Compensation
Choosing compensation capacitor CCMP and resistor RCMP
The current-mode buck converter has 2-poles and 1-zero system. Choosing the appropriate compensation resistor
and capacitor is important to achieve a good load-transient response and good stability.
An example of a DC/DC converter application bode plot is shown in Figure 22.
The compensation resistor, RCMP, determines the cross over frequency FCRS (the frequency at which the total DC-DC
loop-gain falls to 0dB).
Setting a higher cross-over frequency achieves good response speed, but less stability. On the other hand, setting the
cross-over frequency to a lower value may result to better stability, but poorer response speed.
Setting the cross-over frequency to 1/10 of the switching frequency shows good performance at most applications.
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BD9328EFJ
(a) Choosing phase compensation resistor RCMP
The compensation resistor RCMP can be calculated by the following formula:
RCMP 
2  VOUT  f CRS  COUT
VFB  GMP  GMA

Where:
VOUT is the Output voltage
fCRS is the Cross over frequency
COUT is the Output capacitor
VFB is the Internal feedback voltage (0.9V(TYP))
GMP is the Current Sense Gain (7.8A/V(TYP))
GMA is the Error Amplifier Trans-conductance (300µA/V(TYP))
Setting VOUT= 3.3V, fCRS= 38kHz, COUT= 20µF;
RCMP 
2  3.3  38k  20 
 7482 .5  7.5k
0.9  7.8  300 
[ ]
(b) Choosing phase compensation capacitor CCMP
For stability of the DC/DC converter, cancellation of the phase delay that derives from output capacitor COUT and
resistive load ROUT is possible by inserting the phase advance.
The phase advance can be added by the zero on compensation resistor RCMP and capacitor CCMP.
Making fZ= fCRS / 6 gives a first-order estimate of CCMP.
Compensation Capacitor
CCMP 
1
2  RCMP  fz
F 
Setting fZ= fCRS/6 = 6.3kHz;
Compensation Capacitor
C CMP 
1
2  RCMP  6.3k
 3.368  10 9  3.3  10 9
[F ]
However, the best values for zero and FCRS differ between applications. Decide the values accordingly after
calculation using the formula above and confirmation on the actual application.
(c) The condition of the loop compensation stability
The stability of DC/DC converter is important. To ensure operation stability, check if the loop compensation has
enough phase-margin. For the condition of loop compensation stability, the phase-delay must be less than 150
degrees at 0 dB Gain.
Feed-forward capacitor, CRUP, boosts phase margin over a limited frequency range and is sometimes used to
improve loop response. CRUP will be more effective if RUP >> RUP||RDW
V OUT
A
(a)
Gain [dB]
C RUP
R UP
FB
GBW(b)
COMP
-
0
+
R DW
R CMP
0.9V
C CMP
Phase
PHASE
F
CRS
fFCRS
0
-90°
-90
PhaseMARGIN
Margin
PHASE
-180°
-180
Figure 21
F
Figure 22
(3) Design of Feedback Resistance constant
Set the feedback resistance as shown below.
0.9V
VOUT 
VOUT
R1  R 2
 0.9
R2
[V ]
+
R1
ERR
FB
-
R2
Figure 23
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BD9328EFJ
4. Soft Start Function
ERRAMP
ISS 10µA
↓
COMP
SS
+
+
An adjustable soft-start function to prevent high inrush current
during start-up is available.
The soft-start time is set by the external capacitor connected
to SS pin.
The soft start time is given by
t SS s   2.2  C SS / I SS
CSS
-
The charge time of CSS
t SS 1 s   0.6  C SS / I SS
Figure 24
The SS terminal rising time
t SS 2 s   1.6  C SS / I SS
Setting CSS= 0.1µF
t SS [ s ]  (0.6  1.6)  0.1 / 10   22
[ ms ]
Please confirm the overshoot of the output voltage and inrush
current in deciding the SS capacitor value.
5. EN Function
VIN
EN
The EN terminal controls the IC’s shut down.
Leaving EN terminal open shuts down the IC.
To start the IC, the EN terminal should be connected to VIN or
to another power source.
When the EN voltage exceeds 1.2V (typ), the IC starts
operating.
66 kΩ(typ)
91 kΩ(typ)
RREN
EN
EN
(Attention)
If the falling edge of EN input is too slow, output chattering
occurs. This may cause large inverse current from output to
input to flow and VIN voltage to increase, leading to
destruction of the IC. Thus, set the fall time of EN signal within
100µs when controlling the ON/OFF operation of the IC.
This requirement is not needed when EN pin is connected
with VIN and EN is not controlled.
ON/OFF
Signal
As a recommendation, control EN with an open drain
MOSFET connected as shown on Figure 25.
Figure 25
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6. Layout Pattern Consideration
Two high pulsing current loops exist in the buck regulator system. The first loop, when FET is ON, starts from the input
capacitors, to the VIN terminal, to the SW terminal, to the inductor, to the output capacitors, and then returns to the input
capacitor through GND. The second loop, when FET is OFF, starts from the low FET, to the inductor, to the output
capacitor, and then returns to the low FET through GND. To reduce the noise and improve the efficiency, please minimize
these two loop areas. The input capacitor, output capacitor and the low FET should be connected to the PCB’s GND plain.
PCB Layout may greatly affect the thermal performance, noise and efficiency. So please take extra care when designing
PCB Layout patterns.
L
VIN
CIN
FET
VOUT
COUT
Figure 26. Current Loop in Buck Regulator System
(1) The thermal Pad on the back side of the IC has the greatest thermal conduction into the chip. So using the GND
plane as broad and wide as possible can help thermal dissipation. Adding thermal via for dissipation of heat into the
different layers is also effective.
(2) The input capacitors should be connected as close as possible to the VIN terminal.
(3) When there is an unused area on the PCB, please arrange the copper foil plain of DC nodes, such as GND, VIN and
VOUT for better heat dissipation of the IC or circumference parts.
(4) To avoid the noise influence from AC coupling with the other lines, keep the switching lines such as SW as short as
possible, and coil traces as short and as thick as possible.
(5) Keep sensitive signal traces such as traces connected to FB and COMP away from SW pin.
(6) The inductor and the output capacitors should be placed close to SW pin as much as possible.
CIN
L
BST
SS
VIN
EN
SW
COMP
GND
FB
COUT
VOUT
Figure 27. An example of PCB Layout Pattern
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I/O Equivalence Circuit
1.BST
3.SW
VIN
5.FB
VIN
VIN
REG
SW
6.COMP
VIN
7.EN
8.SS
VIN
VIN
VIN
Figure 28. I/O Equivalence Circuit
Power Dissipation
: Pd [mW]
POWER
DISSIPATION:
PD [mW]
Power Dissipation
4000
HTSOP-J8 Package
On 70mm x 70mm x 1.6 mm glass epoxy PCB
(4)3760mW
(1) 1-layer board (Backside copper foil area 0 mm x 0 mm)
(2) 2-layer board (Backside copper foil area 15 mm x 15 mm)
(3) 2-layer board (Backside copper foil area 70 mm x 70 mm)
(4) 4-layer board (Backside copper foil area 70 mm x 70 mm)
3000
(3)2110mW
2000
(2)1100mW
1000
(1)820mW
0
0
25
50
75
100
125
150
AmbientTEMPERATURE:
Temperature : Ta Ta
[°C]
AMBIENT
[°C]
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BD9328EFJ
Operational Notes
1.
Reverse Connection of Power Supply
Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when
connecting the power supply, such as mounting an external diode between the power supply and the IC’s power
supply pins.
2.
Power Supply Lines
Design the PCB layout pattern to provide low impedance supply lines. Separate the ground and supply lines of the
digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the analog
block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and
aging on the capacitance value when using electrolytic capacitors.
3.
Ground Voltage
Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition.
4.
Ground Wiring Pattern
When using both small-signal and large-current ground traces, the two ground traces should be routed separately but
connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal
ground caused by large currents. Also ensure that the ground traces of external components do not cause variations
on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance.
5.
Thermal Consideration
Should by any chance the power dissipation rating be exceeded the rise in temperature of the chip may result in
deterioration of the properties of the chip. The absolute maximum rating of the Pd stated in this specification is when
the IC is mounted on a 70mm x 70mm x 1.6mm glass epoxy board. In case of exceeding this absolute maximum
rating, increase the board size and copper area to prevent exceeding the Pd rating.
6.
Recommended Operating Conditions
These conditions represent a range within which the expected characteristics of the IC can be approximately
obtained. The electrical characteristics are guaranteed under the conditions of each parameter.
7.
Inrush Current
When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush
current may flow instantaneously due to the internal powering sequence and delays, especially if the IC
has more than one power supply. Therefore, give special consideration to power coupling capacitance,
power wiring, width of ground wiring, and routing of connections.
8.
Operation Under Strong Electromagnetic Field
Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction.
9.
Testing on Application Boards
When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may
subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply
should always be turned off completely before connecting or removing it from the test setup during the inspection
process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during
transport and storage.
10. Inter-pin Short and Mounting Errors
Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in
damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin.
Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment)
and unintentional solder bridge deposited in between pins during assembly to name a few.
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TSZ22111・15・001
15/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
Datasheet
BD9328EFJ
Operational Notes – continued
11. Unused Input Pins
Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and
extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small
charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and
cause unexpected operation of the IC. So unless otherwise specified, unused input pins should be connected to the
power supply or ground line.
12. Regarding the Input Pin of the IC
This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them
isolated. P-N junctions are formed at the intersection of the P layers with the N layers of other elements, creating a
parasitic diode or transistor. For example (refer to figure below):
When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.
When GND > Pin B, 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, operational faults, or physical damage. Therefore, conditions that cause these diodes to
operate, such as applying a voltage lower than the GND voltage to an input pin (and thus to the P substrate) should
be avoided.
Figure 29. Example of monolithic IC structure
13. Thermal Shutdown Circuit(TSD)
This IC has a built-in thermal shutdown circuit that prevents heat damage to the IC. Normal operation should always
be within the IC’s power dissipation rating. If however the rating is exceeded for a continued period, the junction
temperature (Tj) will rise which will activate the TSD circuit that will turn OFF all output pins. When the Tj falls below
the TSD threshold, the circuits are automatically restored to normal operation.
Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no
circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from
heat damage.
14. Over Current Protection Circuit (OCP)
This IC incorporates an integrated overcurrent protection circuit that is activated when the load is shorted. This
protection circuit is effective in preventing damage due to sudden and unexpected incidents. However, the IC should
not be used in applications characterized by continuous operation or transitioning of the protection circuit.
15. EN control speed
Chattering happens if standing lowering speed is slow when standing of EN pin is lowered. The reverse current in
which the input side and the pressure operation are done from the output side is generated when chattering operates
with the output voltage remained, and there is a case to destruction. Please set to stand within 100us when you
control ON/OFF by the EN signal.
16. About output voltage when EN terminal on
When restarting by EN terminal, BD9328EFJ starts from 0V. When an electric charge is left in an output capacitance at
this time, electric current discharge from an output capacitance is performed. When many electric charges are left in
an output capacitance, this electrical current discharge becomes big, and BD9328EFJ sometimes comes to
destruction. Therefore please do the discharge control to follow conditions of output voltage when EN terminal on.
In case of output capacitor value is less than 100 μF,: Please set the output voltage less than 2.0V when EN terminal on.
In case of output capacitor value is more than 100 μF,: Please set the output voltage based on the next formula.
(Output voltage when EN terminal on [V]) <
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© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
9.15 x ( Output capacitance [μF] )
16/19
(-0.33)
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
Datasheet
BD9328EFJ
Ordering Information
B
D
9
3
2
8
E
F
J
Package
EFJ : HTSOP-J8
Part Number
-
E2
Packaging and forming specification
E2: Embossed tape and reel
Marking Diagram
HTSOP-J8(TOP VIEW)
Part Number Marking
D
9
3
2
8
LOT Number
1PIN MARK
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© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
17/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
Datasheet
BD9328EFJ
Physical Dimension Tape and Reel Information
Package Name
HTSOP-J8
<Tape and Reel information>
Tape
Embossed carrier tape
Quantity
2500pcs
Direction
of feed
E2
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
Direction of feed
1pin
Reel
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© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
)
∗ Order quantity needs to be multiple of the minimum quantity.
18/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
Datasheet
BD9328EFJ
Revision History
Date
Revision
11.Apr.2012
02.Sep.2014
16.Feb.2015
001
002
003
Changes
New Release
Applied the ROHM Standard Style and improved understandability.
Add “16.about output voltage when EN terminal on” in Operational Notes
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TSZ22111・15・001
19/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
Datasheet
Notice
Precaution on using ROHM Products
1.
Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
(Note 1)
, transport
intend to use our Products in devices requiring extremely high reliability (such as medical equipment
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN
USA
EU
CHINA
CLASSⅢ
CLASSⅡb
CLASSⅢ
CLASSⅢ
CLASSⅣ
CLASSⅢ
2.
ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3.
Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4.
The Products are not subject to radiation-proof design.
5.
Please verify and confirm characteristics of the final or mounted products in using the Products.
6.
In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7.
De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual
ambient temperature.
8.
Confirm that operation temperature is within the specified range described in the product specification.
9.
ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1.
When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2.
In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must
be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,
please consult with the ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice-GE
© 2013 ROHM Co., Ltd. All rights reserved.
Rev.004
Datasheet
Precautions Regarding Application Examples and External Circuits
1.
If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2.
You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1.
Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2.
Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3.
Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4.
Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
QR code printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act,
please consult with ROHM representative in case of export.
Precaution Regarding Intellectual Property Rights
1.
All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data. ROHM shall not be in any way responsible or liable
for infringement of any intellectual property rights or other damages arising from use of such information or data.:
2.
No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the information contained in this document.
Other Precaution
1.
This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2.
The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3.
In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4.
The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
Notice-GE
© 2013 ROHM Co., Ltd. All rights reserved.
Rev.004
Datasheet
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3.
The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or
concerning such information.
Notice – WE
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