Datasheet
4.2V to 18V, 2A 1ch
Synchronous Buck Converter with
Integrated FET
BD9328EFJ
General Description
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.
Key Specifications
Input Voltage Range:
4.2V to 18V
Output Voltage Range:
0.9V to (V
IN
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
W (Typ)
D (Typ)
H (Max)
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
Package
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
C_SS
0.1μF
COMP
SS
EN
FB
R_PC
7.5kΩ
R_DW
10kΩ
R_UP
27kΩ
Thermal Pad
(to be shorted to GND)
BST
VIN
GND
SW
V
IN
= 12V
C_VC1
10μF
R_BS
22Ω
C_BS
0.1μF
L
V
OUT
= 3.3V
10µH
C_CO1
20μF
R_BS protect from VIN-BST short destruction.
Figure 1. Typical Application Circuit
〇Product
structure : Silicon monolithic integrated circuit
www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・14・001
〇This
product has no designed protection against radioactive rays
1/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
BD9328EFJ
Pin Configuration
(TOP VIEW)
SS
EN
COMP
FB
Datasheet
Block Diagram
V
IN
BST
VIN
SW
GND
Figure 2. Pin Configuration
Figure 3. Block Diagram
Pin Description
Pin No.
1
2
3
4
5
6
7
8
Pin Name
BST
VIN
SW
GND
FB
COMP
EN
SS
Power input
Power switching output
Ground
Feedback input
Compensation node
Enable input
Soft start control input
Function
High-side gate drive boost input
www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111½15½001
2/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
BD9328EFJ
Absolute Maximum Ratings
(Ta = 25
°C
)
Parameter
Supply Voltage
Switch Voltage
Power Dissipation for HTSOP-J8
Package Thermal Resistance
θja
(Note 2)
Package Thermal Resistance
θjc
(Note 2)
Operating Temperature Range
Storage Temperature Range
Maximum Junction Temperature
BST Voltage
EN Voltage
All Other Pins
Symbol
V
IN
V
SW
Pd
θja
θjc
Topr
Tstg
Tjmax
V
BST
V
EN
V
OTH
Rating
20
20
3.76
(Note 1)
29.27
3.75
-40 to +85
-55 to +150
150
V
SW
+7
20
20
Unit
V
V
W
°C /W
°C /W
°C
°C
°C
V
V
V
Datasheet
(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
Supply Voltage
SW Voltage
Output Current
Output Voltage Range
Symbol
V
IN
V
SW
I
SW3
V
RANGE
Rating
Min
4.2
-0.5
-
0.9
Typ
12
-
-
-
Max
18
+18
2
V
IN
x 0.7
Unit
V
V
A
V
Electrical Characteristics
(Unless otherwise specified V
IN
=12V Ta=25°C)
Parameter
Error Amplifier Block
FB Input Bias Current
Feedback Voltage1
Feedback Voltage2
SW Block – SW
Hi-Side FET ON-Resistance
Lo-Side FET ON-Resistance
Hi/Lo-Side FET Leak Current
Switch Current Limit
Maximum Duty Cycle
General
Enable Sink Current
Enable Threshold Voltage
Under Voltage Lockout Threshold
Under Voltage Lockout Hysteresis
Soft Start Current
Soft Start Time
Operating Frequency
Circuit Current
Standby Current
I
EN
V
EN
V
UVLO
V
HYS
I
SS
t
SS
f
OSC
I
CC
I
QUI
90
1.0
3.5
-
5
-
300
-
-
180
1.2
3.75
0.3
10
22
380
1.2
15
270
1.4
4.0
-
15
-
460
3
27
µA
V
V
V
µA
ms
kHz
mA
µA
V
FB
= 1.5V, V
EN
= 12V
V
EN
= 0V
V
SS
= 0 V
C
SS
= 0.1 µF
V
IN
Rising
V
EN
= 12V
R
ONH
R
ONL
I
LEAKN
I
LIMIT3
M
DUTY
-
-
-
3
-
0.15
0.13
0
-
90
-
-
10
-
-
Ω
Ω
µA
A
%
V
FB
= 0V
I
SW
= -0.8A
I
SW
= 0.8A
V
IN
= 18V,
V
SW
= 0V / 18V
I
FB
V
FB1
V
FB2
-
0.886
0.882
0.02
0.900
0.900
2
0.914
0.918
µA
V
V
Voltage Follower
Ta=-25°C to +85°C
Symbol
Limit
Min
Typ
Max
Unit
Conditions
www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
3/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
BD9328EFJ
Typical Performance Curves
(Unless otherwise specified, V
IN
= 12V Ta= 25°C)
Datasheet
I
CC
(mA)
V
IN
(V)
Figure 4. Circuit Current vs Input Voltage
(No Switching)
I
CC
(µA)
V
IN
(V)
Figure 5. Standby Current vs Input Voltage
(Shutdown Mode)
I
FB
(µA)
V
FB
(V)
Figure 6. Input Bias Current vs
Feedback Voltage
Temperature [°C]
Figure 7. Feedback Voltage vs Temperature
www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
4/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
BD9328EFJ
Typical Performance Curves - continued
390
385
380
Datasheet
f
OSC
(kHz)
FOSC
(kHz)
R
ON
[Ω]
375
370
365
360
-4 0
-2 0
0
20
40
60
80
Temperature [°C]
Figure 8. Hi-Side, Low-Side FET
ON-Resistance vs Temperature
T E M P ( °C )
Temperature [°C]
Figure 9. Operating Frequency vs Temperature
95
90
85
80
75
70
65
60
55
50
0
500
1000
Io[mA]
I
O
[mA]
1500
2000
Soft Start Time [ms]
Efficiency
Efficiency[%]
C
SS
[µF]
Figure 10. STEP-Down Efficiency vs I
O
(V
IN
= 12V V
OUT
= 3.3V L=10µH)
Figure 11. Soft Start Time vs
Soft Start Capacitor
www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
5/19
TSZ02201-0323AAJ00020-1-2
16.Feb.2015 Rev.003
京公网安备 11010802033920号
EEWORLD
