Datasheet
Dual Synchronous Buck Converter
BD93291EFJ
●Description
The BD93291EFJ is a dual synchronous buck converter.
It integrates wide input voltage range (8.0V to 26V) synchronous
buck converter and low input voltage (Vout1 : 5.0V)
synchronous buck converter.
The IC also incorporates a new technology called
H3RegTM, a Rohm proprietary control method which
facilitates ultra-high transient response against changes in
load. SLLM (Simple Light Load Mode) technology is also
integrated to improve efficiency when powering lighter
loads. For protection and ease of use, the IC also
incorporates soft start.
Space-saving and high efficient switching regulator can be
achieved due to built-in N-MOSFET power transistor in
HTSOP-J8 package.
●Features
・Dual Synchronous Buck Converter in small package.
・standby mode ( Istandby = 0uA )
・High Voltage Synchronous Buck Converter(Vout1)
Wide input range(8.0V to 26V) *absolute voltage 30V
H3RegTM DC/DC Converter Controller included
Output Current 1.7A *1
FET on resistance High-side 0.175Ω/Low-side 0.175Ω
Internal soft-start function
Switching Frequency 300 to 600kHz
(*According to input/output conditions)
Fixed output voltage (5.0V ± 1.5%; Normal Mode)
・Low Voltage Synchronous Buck Converter(Vout2)
Input voltage range 5.0V(VOUT1)
H3RegTM DC/DC Converter Controller included
Output Current 0.5A *1
FET on resistance High-side 0.25Ω/Low-side 0.25Ω
Internal soft-start function
Switching Frequency 1.5M to 2.5MHz
(*According to input/output conditions)
Feedback voltage (0.8V ± 1.5%; Normal Mode)
・Protection Circuits
Under Voltage Lockout Protection
Thermal Shutdown
Over Current Protection
・HTSOP-J8 Package with Exposed thermal PAD.
●Applications
・Distributed Power System
・Pre-Regulator for Linear Regulator
●Typical Application Circuit
VOUT2
C_UP
R_DW
R_UP
*1 Vout1 maximum output current capability is 2.5A, and
Vout2 maximum output current capability is 1.5A with the
optimal PCB power consumption design.
C_CO2
L2
C_CO3
GND
5
FBL
6
VOUT
8
BD93291EFJ
C_VC1
○Product structure:Silicon monolithic integrated circuit
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TSZ22111・14・001
2
3
4
BST
EN
VIN
C_BS
1
C_CO1
L1
SW
VOUT1
7
Thermal Pad
(to be shorted to GND)
SWL
●Structure
・Silicon Monolithic Integrated Circuit
●Package
・HTSOP-J8
6.00mm x 4.90mm x 1.00mm
●PIN Configuration (TOP VIEW)
○This product is not designed protection against radioactive rays
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Datasheet
● Block Diagram
VIN
BST
EN
VREG
VREF
VREF
14V
UVLO1
UVLO
TSD
TSD
VOUT1
VIN
VOUT
H3RegTM
Controller
Block
DRV
DRV
LOGIC
LVS
Vout1(5V, Fix)
SW
LVS
OCP
Current
Sense
FB
0.8V
+
EN
Soft
Start
TSD
UVLO1
VOUT
UVLO2
VOUT2
SWL
H3RegTM
Controller
Block
FBL
DRV
DRV
Vout2(3.3V)
LOGIC
0.8V
+
OCP
EN
Soft
Start
Current
Sense
UVLO2
TSD
GND
●Pin Assignment and Pin Function
No.
Symbol
Description
1
SW
Connect the inductor switching node of high voltage buck converter.
This pin is connected to the source node of High side FET and the drain node of Low side FET.
2
BST
Connect 0.1uF Boot Strap capacitor between BST pin and SW pin.
This capacitor is for generating the driving voltage of High-side N-channel MOSFET.
3
EN
This is Enable pin of BD93291EFJ.
High input (2.3V typ.) is output active. Low input (1.8V typ.) is IC shutdown.
The internal impedance of EN pin is high, therefore add capacitor between EN and GND pin to reduce
noise influence when this pin is connected to high-impedance node.
4
VIN
Power supply pin of high voltage buck converter.
This pin is connected to power FET supply and internal control blocks of high voltage buck converter.
Connect to 10uF(recommended value) ceramic capacitor for bias capacitor.
5
GND
This pin is Low-side N-channel MOSFET power ground of high voltage buck converter, Low-side
N-channel MOSFET power ground of low voltage buck converter and analog ground of other blocks.
6
FBL
This pin is output voltage feed-back pin of low voltage buck converter. Refer to ---page regarding the
setting of output voltage.
7
SWL
Connect the inductor switching node of low voltage buck converter.
This pin is connected to the drain node of High side Pch-FET and the drain node of Low side FET.
8
VOUT
This pin is power supply pin of low voltage buck converter and output voltage feed-back pin of high voltage
buck converter. This pin is connected to power FET supply and internal control blocks of low voltage buck
converter. Connect to 10uF(recommended value) ceramic capacitor for bias capacitor.
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Datasheet
●Absolute maximum ratings (Ta = 25°C)
Symbol
Rating
Unit
Supply Voltage 1
VIN
30
V
Switch Voltage 1
VSW
30
V
Supply Voltage 2
VOUT
7.0
V
Switch Voltage 2
VSWL
7.0
Parameter
V
Power Dissipation for HTSOP-J8
Pd
Package thermal resistance θja *2
θja
29.27
℃/W
Package thermal resistance θjc *2
θjc
3.75
℃/W
Operating Temperature Range
Topr
-40 to +85
℃
Storage Temperature Range
Tstg
-55 to +150
℃
Junction Temperature
3760
*1
mW
Tjmax
150
℃
BST Voltage
VBST
VSW+7
V
EN Voltage
VEN
30
V
*1 Derating in done 30.08 mW/℃ for operating above Ta≧25℃(Mount on 4-layer 70.0mm×70.0mm×1.6mm board)
*2 Mount on 4-layer 50mm x 30mm x 1.6mm application board
●Operation Range(Ta= -40 to 85℃)
Symbol
Min
Typ
Max
Unit
Supply Voltage 1
VIN
8.0
14
26
V
Supply Voltage 2
VOUT
-
5.0
-
V
SW Voltage 1
VSW
-0.5
-
26
V
SW Voltage 2
VSWL
-0.5
-
5.5
V
Output voltage range 1 (Fixed)
Vout1
-
5.0
-
V
Output voltage range 2
Vout2
0.8
3.3
4.0
V
Parameter
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Datasheet
●Electrical characteristics (unless otherwise specified VIN=14V, VOUT1=5V, VOUT2=3.3V Ta=25℃)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Conditions
【High Voltage Synchronous Buck Converter】
Output Voltage
VOUT1
4.925
5.0
5.075
V
±1.5%,normal mode
Hi-side FET On-resistance
RONH1
-
0.175
-
Ω
ISW= -0.8A
Lo-side FET On-resistance
RONL1
-
0.175
-
Ω
ISW= 0.8A
VIN= 26V,
VSW = 0V / 26V
Hi/Lo-side FET Leak current
ILEAK1
-
0
10
µA
Switch Current Limit
ILIMIT1
3.0
-
-
A
Soft-start time
VSS1
2.5
5.0
7.5
ms
ON Time
TON1
635
794
953
ns
Minimum Off Time
T OFF1
-
200
-
ns
Fsw1=450kHz(typ)
Iout=0.3A
【Low Voltage Synchronous Buck Converter】
±1.5%,normal mode
Feed-back Voltage
VFBL
0.788
0.8
0.812
V
FBL input bias current
IFBL
-1.0
0
1.0
µA
Hi-side FET On-resistance
RONH2
-
0.25
-
Ω
Lo-side FET On-resistance
RONL2
-
0.25
-
Ω
ISWL= 0.8A
VOUT1= 5.5V,
VSWL = 0V / 5.5V
ISWL= -0.8A
Hi/Lo-side FET Leak current
ILEAK2
-
0
10
µA
Switch Current Limit
ILIMIT2
2.0
-
-
A
Soft-start time
VSS1
1.25
2.5
3.75
ms
ON Time
TON2
264
330
396
ns
Minimum Off Time
T OFF3
-
50
-
ns
IEN
33
56
73
µA
VEN= 14V
Enable Threshold voltage 1
VEN_R
2.2
2.3
2.4
V
Rising
Enable Threshold voltage 2
VEN_F
1.7
1.8
1.9
V
Falling
VIN Under Voltage Lockout threshold
VUVLO1
7.1
7.5
7.9
V
VIN rising
VIN Under Voltage Lockout Hysteresis
VHYS1
-
1.0
-
V
VOUT Under Voltage Lockout threshold
VUVLO2
2.3
2.5
2.7
V
VOUT Under Voltage Lockout Hysteresis
VHYS2
-
0.2
-
V
Circuit Current VIN
ICC_VIN
-
0.6
1.5
mA
ICC_VOUT
-
0.6
1.5
mA
VOUT= 5.5V, VEN=
14V
VFBL= 1.0V, VEN=
14V
5
µA
VEN= 0V
Fsw2=2MHz(typ)
Iout=0.2A
【General】
Enable Sink current
Circuit Current VOUT
Standby Current
IQUI
0
* This product is not designed for protection against radioactive rays
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Datasheet
Ta=25℃, VIN=14V, VOUT1=5V, VOUT2=3.3V)
100
100
95
95
90
90
85
85
Efficiency [%]
Efficiency [%]
●Typical Performance Curves (Unless otherwise noted
80
75
70
80
75
70
65
65
60
60
55
55
50
50
10
100
1000
Iout1 [mA]
10000
Figure 4. VOUT1 Efficiency
(VIN=14V, L=22H)
1000
Iout2 [mA]
10000
VOUT2(AC)
10mV/div
SW
5V/div
SWL
2V/div
1sec/div
Figure 6. VOUT1 Ripple voltage
(VIN=14V, L1=22H, COUT1=22F, Iout=1A)
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100
Figure 5. VOUT2 Efficiency
(VOUT1=5V, VOUT2=3.3V, L=2.2H)
VOUT1(AC)
50mV/div
ISW
1A/div
10
ISWL
1A/div
1sec/div
Figure 7. VOUT2 Ripple voltage
(VOUT1=5V, VOUT2=3.3V, L2=2.2H, COUT2=22F,
Iout=0.3A)
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Datasheet
●Typical Performance Curves (Unless otherwise noted
Ta=25℃, VIN=14V, VOUT1=5V, VOUT2=3.3V) (Continued)
5.20
5.20
5.10
5.10
VOUT1 [V]
VOUT1 [V]
Iout1=10mA
5.00
5.00
4.90
Iout1=1A
4.90
4.80
4.80
0
500
1000
1500
2000
2500
8
10
12
14
16
Iout1 [mA]
18
20
22
24
26
VIN[V]
Figure 8. VOUT1 Load Regulation
(VIN=14V, L1=22H)
Figure 9. VOUT1 Line Regulation
(VIN=14V, L1=22H, Iout1=10mA / 1A)
5.20
800
700
Iout1=10mA
Frequency [kHz]
VOUT1 [V]
5.10
5.00
Iout1=1A
600
500
400
4.90
300
4.80
200
-40
-20
0
20
40
60
80
5
Temperature [℃]
15
20
25
30
VIN [V]
Figure 10. VOUT1 - Temperature
(VIN=14V, L1=22H, Iout1=10mA/1A)
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Figure 11. SW_Frequency - VIN
(VIN=14V, L1=22H, Iout1=1A)
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Datasheet
●Typical Performance Curves (Unless otherwise noted
EN
2V/div
Ta=25℃, VIN=14V, VOUT1=5V, VOUT2=3.3V) (Continued)
VOUT1
2V/div
VOUT1
2V/div
VOUT2
2V/div
VOUT2
2V/div
EN
2V/div
IIN
1A/div
IIN
1A/div
4msec/div
Figure 12. Start up wave form
(VIN=14V, VOUT1=5V, VOUT2=3.3V, L1=22H,
L2=2.2H, COUT1=22F, COUT2=2.2F, Iout1=2A,
Iout2=1A)
4msec/div
Figure 13. Off wave form
(VIN=14V, VOUT1=5V, VOUT2=3.3V, L1=22H,
L2=2.2H, COUT1=22F, COUT2=2.2F, Iout1=2A,
Iout2=1A)
VOUT1 (AC)
200mV/div
VOUT1 (AC)
200mV/div
SW
20V/div
Iout1
2A/div
SW
20V/div
Iout1 0A->2A/10us
Iout1 2A->0A/10us
10sec/div
Iout1
2A/div
10sec/div
1
Figure 15. VOUT1 Transient Response
(VIN=14V, VOUT1=5V, L=22H, COUT=22F)
Iout=2->0A (SR=0.2A/sec)
Figure 14. VOUT1 Transient Response
(VIN=14V, VOUT1=5V, L=22H, COUT=22F)
Iout=0->2A (SR=0.2A/sec)
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Datasheet
●Typical Performance Curves (Unless otherwise noted
Ta=25℃, VIN=14V, VOUT1=5V, VOUT2=3.3V) (Continued)
VOUT2 (AC)
20mV/div
VOUT2 (AC)
20mV/div
SWL
2V/div
SWL
2V/div
Iout2
200mA/div
Iout2 0A->200mA/10us
Iout2 200mA->0A/10us
10sec/div
10sec/div
Figure 16. VOUT2 Transient Response
(VOUT1=5V, VOUT2=3.3V, L2=2.2H,
COUT2=22F),
Iout2=0->200mA (SR=20mA/sec)
Figure 17. VOUT2 Transient Response
(VOUT1=5V, VOUT2=3.3V, L2=2.2H,
COUT2=22F),
Iout2=200mA->0mA (SR=20mA/sec)
VOUT1 2V/div
VOUT2 200mV/div
SW 20V/div
SWL 2V/div
Iout1
2A/div
2sec/div
Figure 18. VOUT1 OCP function
(VIN=14V, VOUT1=5V, VOUT2=3.3V, L1=22H,
COUT1=22F)
(VOUT1 is shorted to GND)
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Iout2
200mA/div
Iout2
2A/div
2sec/div
Figure 19. VOUT2 OCP function
(VIN=14V, VOUT1=5V, VOUT2=3.3V, L2=2.2H,
COUT2=22F)
(VOUT2 is shorted to GND)
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Datasheet
Ta=25℃, VIN=14V, VOUT1=5V, VOUT2=3.3V) (Continued)
3.50
3.50
3.40
3.40
3.30
3.30
VOUT2 [V]
VOUT2 [V]
●Typical Performance Curves (Unless otherwise noted
3.20
3.10
3.20
3.10
3.00
3.00
0
500
1000
Iout [mA]
1500
-40
0
20
40
60
80
Temperature [℃]
Figure 20. VOUT2 Load Regulation
(VOUT1=5V, L=2.2H)
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Figure 21. VOUT2 - Temperature
(VOUT1=5V, L=2.2H, Iout=1.5A)
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Datasheet
●Explanation of Operation
The BD93291EFJ is a dual synchronous buck converter incorporating ROHM’s proprietary H3RegTM CONTROLLA system.
When VOUT1 and VOUT2 drop due to a rapid load change, the system quickly restores VOUT1 and VOUT2 by increasing
the frequency.
3
TM
1. H Reg System
1-1. Normal Operation
When FB falls below the threshold voltage (REF), a drop is detected, activating the H3RegTM CONTROLLA system.
Ton
V OUT
V IN
1
f
[sec]
(1)
HG (Gate of High side MOSFET) output is determined by the formula (1). LG (Gate of Low side MOSFET) output operates
until FB voltage falls below REF voltage after HG becomes OFF. OFF time is restricted by MIN OFF Time ( VOUT1 :
200nsec (typ.), VOUT2 : 50nsec (typ.) ).
Hence, BD93291EFJ runs with a constant on-time by using the input and output voltage to set the internal on-time timer.
1-2. VOUT drops due to a rapid load change
When FB (VOUT) drops due to a rapid load change and the voltage remains below REF, the system quickly restores VOUT
by shortening OFF time of HG (increasing the frequency), improving transient response as shown Figure 22 (b).
FB
FB
REF
REF
HG
Io
LG
HG
LG
(a) Normal operation
(b) Rapid load change
3
Figure 22. H REG System
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Datasheet
●Timing Chart
1. Soft Start Function
Soft start is utilized when the EN pin is set high. Current control takes effect at startup, enabling a moderate “ramping start”
on the output voltage. Soft start time of VOUT1 is 5.0msec (typ) and VOUT2 is 2.5ms (typ).
EN
5.0ms (typ)
5V(fixed)
2.5V (typ)
VOUT1
2.5ms (typ)
3.3V
VOUT2
Figure 23. Soft Start Timing Chart
●Protection Operation
1. OCP Operation
Normally, when FB voltage falls below REF voltage, HG becomes high. However, if the peak current through the inductor
(IL) exceeds OCP current value (IOCP) during HG=ON, HG become OFF immediately and IL is restricted by IOCP. As the result,
the output voltage can decrease as the frequency and duty are changed.
When OCP is released in the state that the output has decreased by OCP operation, the output voltage might rise up due to
high-speed load response.
Figure 24. OCP Timing Chart
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2. TSD Operation (Self Recovery)
TSD is self-activating. If the junction temperature exceeds Tj = 175℃, and HG, LG, and SS become Low.
The IC becomes standby when TSD operating.
When Tj falls below 150℃, it returns to standard operation.
3. UVLO Operation
UVLO operates when VIN voltage falls below 6.5V, and HG and LG become Low.
The IC becomes standby when UVLO operating.
UVLO is released when VIN goes up to 7.5V, and starts standard operation
●Selection of Components Externally Connected
1. Output LC Filter Selection (Buck Converter)
1-1. Inductor (L) Selection
The Output LC filter is required to supply constant current to the output load. A larger value inductance at this filter results
in less inductor ripple current (∆IL) and less output ripple voltage. However, the larger value inductors tend to have less
fast load transient-response, a larger physical size, a lower saturation current and higher series resistance. A smaller
value inductance has almost opposite characteristics above.
The value of ΔIL is shown as formula (2). The larger value of the inductance or the faster switching frequency make the
lower ripple voltage.
∆I L
VIN
V OUT V OUT
L f V IN
[A]
(2)
The proper output ripple current setting is about 30% of maximum output current.
IL 0 . 3 IOUTMAX
L
VIN
V OUT V OUT
IL f V IN
[A]
(3)
[H]
(4)
(ΔIL : output ripple current、f : switching frequency)
※A larger current than the inductor’s rated current will cause magnetic saturation in the inductor, and decrease efficiency.
When selecting an inductor, be sure to allow enough margins to assure that peak current does not exceed the inductor’s
rated current value.
※To minimize loss of inductor and improve efficiency, choose a inductor with a low resistance (DCR, ACR).
VIN
HG
IL
VOUT
SW
L
LG
ΔIL
COUT
Figure 25. Inductor Ripple Current
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Datasheet
1-2. Output Capacitor (COUT) Selection
Output Capacitor (COUT) has a considerable influence on output voltage regulation due to a rapid load change and
smoothing output ripple voltage. Determine the capacitor by considering the value of capacity, the equivalent series
resistance, and equivalent series inductance. Also, make sure the capacitor’s voltage rating is high enough for the set
output voltage (including ripple).
Output ripple voltage is determined as in formula (5) below.
ΔVOUT=ΔIL/(8×COUT×f)+ESR×ΔIL +ESL×ΔIL / Ton
[V]
(5)
(ΔIL Output ripple current、ESR: Equivalent series resistance、ESL: Equivalent series inductance)
Also, give consideration to the conditions in formula (6) below for output capacitance, bearing in mind that output rise time
must be established within the fixed soft start time. As output capacitance, bypass capacitor will be also connected to
output load side (CEXT, Figure 26). Please set the over current detection value with regards to these capacitance.
C OUT
SS IOCP IOUT
VOUT
[F]
(6)
(SS : Soft Start time, IOCP : OCP Current Limit, IOUT : Output Current)
Note: an improper output capacitor may cause startup malfunctions.
VIN
HG
VOUT
SW
L
ESR
Load
LG
CEXT
ESL
COUT
Figure 26. Output Capacitor
2. Input Capacitor (CIN) Selection
In order to prevent transient spikes in voltage, the input capacitor should have a low
enough ESR resistance to fully support a large ripple current. The formula for ripple
current IRMS is given in equation (7) as below.
VIN
CIN
HG
VOUT
SW
L
COUT
IRMS IOUT
VOUT (VIN VOUT )
LG
Where VIN =2×VOUT, IRMS=
Figure 27. Input Capacitor
[A]
VIN
(7)
IOUT
2
A low ESR capacitor is recommended to reduce ESR loss and improve efficiency.
Capacitor Cout between VOUT and GND must be placed near the VOUT pin.
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Datasheet
3. VOUT2 Output Voltage Setting
The IC controls output voltage as REF≒VFBL.
However, the actual output voltage will also reflect the average ripple voltage value.
The VOUT2 output voltage is set with a resistor divider from the output node to the FBL pin. The formula for output voltage
is given in (8) below:
R_UP+RD_W
R_DW
VOUT2 =
× REF +∆VOUT
REF = VFBL(TYP 0.8V) + 0.02 – (ON DUTY × 0.05)
ON DUTY =
[V]
(8)
[V]
(9)
VOUT2
(10)
VOUT1
C_UP is needed to feedback output voltage ripple to FBL pin, the value is calculated to
C_UP =
11e-6 (+/-30%)
R_UP
[F]
(11)
Please refer to eq. (5) regarding ∆VOUT.
VOUT1
REF
H3RegTM
CONTROLLA
R
Output Voltage
VOUT2
Q
Driver
Circuit
S
VFBL
R_UP
C_UP
R_DW
Figure 28. Output Voltage VOUT2 Setting
4. Relationship between Output Voltage and ONTIME
BD93291EFJ is a dual synchronous buck converter controlling constant ONTIME. The ONTIME (Ton) depends on the
output voltage settings, as described by the formula (12).
Ton ≒
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VOUT
1
VIN Frequency
[sec]
14/21
(12)
TSZ02201-0323AAJ00300-1-2
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BD93291EFJ
Datasheet
●PCB Layout Guide
Two high pulsing current flowing 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 area.
Especially input capacitor and output capacitor should be connected to GND plain.
PCB Layout may affect the thermal performance, noise and efficiency greatly. So please take extra care when designing PCB
Layout patterns.
L
VIN
CIN
FET
VOUT
COUT
GND
Figure 29. Current loop Buck regulator system
・The thermal pad on the back side of IC has the great thermal conduction to the chip. So using the GND plain as broad and
wide as possible can help thermal dissipation. And a lot of thermal via for helping the spread of heat to the different layer is
also effective.
・The input capacitors (C_VC1 and C_CO3) should be connected as close as possible to the VIN or VOUT terminal.
Especially, C_CO3 between VOUT and GND must be placed near the VOUT pin, and keep the distance "b" less than 2mm.
・When there is unused area on PCB, please arrange the copper foil plain of DC nodes, such as GND, VIN and VOUT for
helping heat dissipation of IC or circumference parts.
・To avoid the noise influence from AC combination with the other line, keep the switching line such as SW and SWL not
extend as much as possible, and trace shortly and thickly to coil L1 and L2.
・Keep sensitive signal traces such as trace connected FBL away from SW and SWL pins.
・The inductors and the output capacitors should be placed close to SW or SWL pins as much as possible.
・Keep VOUT pattern width "a" more than 3mm to stable the 5V output.
Figure 30. Example of PCB layout pattern
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BD93291EFJ
Datasheet
●List of Evaluation Board Components
C_UP
VOUT2
R_DW
R_UP
C_CO2
L2
C_CO3
Thermal Pad
(to be shorted to GND)
L1
VOUT1
C_VC1
C_BS
C_CO1
Figure 31. Typical Application Circuit
・Recommended Components List (VIN=14V, VOUT1=5V, VOUT2=3.3V)
Symbol
Part
Value
Manufacture
Series
C_VC1
Ceramic Capacitor
10uF
murata
GRM32DF51H106ZA01L
C_BST
Ceramic Capacitor
0.1uF
murata
GRM188F11H104ZA01
L1
Coil
22uH
TDK
SLF10165 220M 2R4
L2
Coil
2.2uH
TDK
VLF 4012S 2R2M 1R3
C_CO1
Ceramic Capacitor
22uF
murata
GRM21BB31A226ME51L
C_CO2
Ceramic Capacitor
22uF
murata
GRM21BB31A226ME51L
C_CO3
Ceramic Capacitor
10uF
murata
GRM21BB31A106ME18
C_UP
Ceramic Capacitor
680pF
murata
GRM1882C1H681JA01
R_UP
Resistance
16kΩ
ROHM
MCR03 1608size Tolerance F
R_DW
Resistance
5.1kΩ
ROHM
MCR03 1608size Tolerance F
※The above components list is an example. Please check actual circuit characteristics on the application carefully before use.
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12. Nov. 2012 Rev.001
BD93291EFJ
Datasheet
●I/O Equivalence circuit
SW
BST
EN
EN
VIN
VIN
REG
BST
VIN
SW
SW
FBL
SWL
VOUT
VOUT
VOUT
VOUT
VOUT
SWL
FBL
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SWL
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BD93291EFJ
Datasheet
●Operational Notes
(1) Absolute Maximum Ratings
Use of the IC in excess of absolute maximum ratings may result in damage to the IC. Assumptions should not be made
regarding the state of the IC (e.g., short mode or open mode) when such damage is suffered. If operational values are
expected to exceed the maximum ratings for the device, consider adding protective circuitry (such as fuses) to eliminate
the risk of damaging the IC.
(2) GND voltage
The potential of the GND pin must be the minimum potential in the system in all operating conditions.
(3) Thermal design
Use a thermal design that allows for a sufficient margin for power dissipation (Pd) under actual operating conditions
(4) Inter-pin Shorts and Mounting Errors
Use caution when orienting and positioning the IC for mounting on printed circuit boards. Improper mounting may result in
damage to the IC. Shorts between output pins or between output pins and the power supply and GND pins caused by
poor soldering or foreign objects may result in damage to the IC.
(5) Operation in Strong Electromagnetic Fields
Using this product in strong electromagnetic fields may cause IC malfunction. Caution should be exercised in applications
where strong electromagnetic fields may be present.
(6) ASO (Area of Safe Operation)
When using the IC, ensure that operating conditions do not exceed absolute maximum ratings or ASO of the output
transistors.
(7) Testing on application boards
When testing the IC on an application board, connecting a capacitor directly to a low-impedance 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 a jig or fixture during the evaluation process. To prevent
damage from static discharge, ground the IC during assembly and use similar precautions during transport and storage.
(8) Electrical Characteristics
The electrical characteristics indicated in this datasheet may change upon the conditions of temperature, supply voltage,
and external components. Please validate/verify your design at the worst case conditions.
(9) Not of a radiation-resistant design.
(10) Back Electromotive Force
If a large inductive load is connected at the output pin that might cause introducing back electromotive force at the start up
and at the output disable, please insert protection diodes.
OUTPUT
PIN
Figure 32. Back Electromotive Force
(11) Regarding input pins of the IC
This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them isolated.
PN junctions are formed at the intersection of these P layers with the N layers of other elements, creating parasitic diodes
and/or transistors. For example (refer to the figure below):、
•When GND > Pin A and GND > Pin B, the PN junction operates as a parasitic diode
•When GND > Pin B, the PN junction operates as a parasitic transistor
Parasitic diodes occur inevitably in the structure of the IC, and the operation of these parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Accordingly, 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.
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BD93291EFJ
Datasheet
Resistor
Transistor (NPN)
Pin B
Pin A
C
Pin B
B
E
Pin A
P
N
P
+
P
N
+
N
N
Parasitic
element
P
+
N
P substrate
Parasitic element
B
P
P
+
N
C
E
Parasitic
element
P substrate
GND
Parasitic element
GND
GND
Other adjacent
elements
GND
Figure 33. Example of IC structure
(12) Ground Wiring Pattern
When using both small-signal and large-current GND traces, the two ground traces should be routed separately but
connected to a single ground potential within the application in order to avoid variations in the small-signal ground
caused by large currents. Also ensure that the GND traces of external components do not cause variations on GND
voltage.
(13) Operating Condition
The electrical characteristics indicated in this datasheet are not guaranteed for the whole operational and temperature
ranges, however these characteristics do not significantly fluctuate within the operational and temperature ranges.
(14) Thermal shutdown (TSD) circuit
The IC incorporates a built-in thermal shutdown circuit, which is designed to turn the IC off completely in the event of
thermal overload. It is not designed to protect the IC from damage or guarantee its operation. ICs should not be used
after this function has activated, or in applications where the operation of this circuit is assumed. If the thermal shutdown
is activated while the load current exists, the output may possibly be latched off at the release of the thermal shutdown.
TSD ON Temp.[℃]
175
(typ.)
Hysteresis Temp[℃]
25
(typ.)
(15) Heat Sink (FIN)
The heat sink (FIN) is connected to the substrate. Please connect it to GND.
Status of this document
The English 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
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TSZ02201-0323AAJ00300-1-2
12. Nov. 2012 Rev.001
BD93291EFJ
Datasheet
POWER DISSIPATION: PD [mW]
●Thermal Derating Curves
4000
(4)3760mW
3000
(3)2110mW
2000
(2)1100mW
1000
(1)820mW
0
0
50
25
75
100
125
150
AMBIENT TEMPERATURE: Ta [°C]
Figure 34. Thermal derating curve
(HTSOP-J8)
HTSOP-J8 Package
On 70 70 1.6 mm glass epoxy PCB
(1) 1-layer board (Backside copper foil area 0 mm 0 mm)
(2) 2-layer board (Backside copper foil area 15 mm 15 mm)
(3) 2-layer board (Backside copper foil area 70 mm 70 mm)
(4) 4-layer board (Backside copper foil area 70 mm 70 mm)
●Ordering Information
B
D
9
3
2
9
Part Number
1
E
F
J
-
Package
EFJ: HTSOP-J8
E2
Packaging and forming specification
E2: Embossed tape and reel
●Physical Dimension 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
1pin
Reel
)
Direction of feed
∗ Order quantity needs to be multiple of the minimum quantity.
●Marking Diagram
HTSOP-J8(TOP VIEW)
Part Number Marking
D 9 3 2 9 1
LOT Number
1PIN MARK
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TSZ02201-0323AAJ00300-1-2
12. Nov. 2012 Rev.001
BD93291EFJ
Datasheet
●Revision History
Date
Revision
12.Nov.2012
001
Changes
New Release
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12. Nov. 2012 Rev.001
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; if flow soldering method is preferred, please consult with the
ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice - GE
© 2014 ROHM Co., Ltd. All rights reserved.
Rev.002
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.
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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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