ROHM BD9528MUV-E2

Hi-performance Regulator IC Series for PCs
Main Power Supply ICs
for Note PC (Linear Regulator Integrated)
No.10030EAT26
BD9528MUV
●Description
BD9528MUV is a 2ch switching regulator controller with high output current which can achieve low output voltage (1.0V～
5.5V) from a wide input voltage range (5.5V～28V). High efficiency for the switching regulator can be realized by utilizing an
external N-MOSFET power transistor. A new technology called H3RegTM(High speed, High efficiency, High performance)
is a Rohm proprietary control method to realize ultra high transient response against load change. SLLM (Simple Light Load
Mode) technology is also integrated to improve efficiency in light load mode, providing high efficiency over a wide load
range. For protection and ease of use, 2ch LDO (5V/100mA, 3.3V/100mA), the soft start function, variable frequency
function, short circuit protection function with timer latch, over voltage protection, and Power good function are all built in.
This switching regulator is specially designed for Main Power Supply of laptop PC.
●Features
1) 2ch H3REGTM DC/DC Converter controller
2) Adjustable Simple Light Load Mode (SLLM), Quiet Light Load Mode (QLLM) and Forced continuous Mode
3) Thermal Shut Down (TSD), Under Voltage LockOut (UVLO), Over Current Protection (OCP),
Over Voltage Protection (OVP), Short circuit protection with 0.75ms timer-latch (SCP)
4) Soft start function to minimize rush current during startup
5) Switching Frequency Variable (f=200kHz～500kHz)
6) Built-in Power good circuit
7) Built-in 2ch Linear regulator (5V/100mA,3.3V/100mA)
8) Built in reference voltage(0.7V)
9) VQFN032V5050 package
10) Built-in BOOT-Di
11) Built-in output discharge
●Applications
Laptop PC, Desktop PC, LCD-TV, Digital Components
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1/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Absolute maximum ratings (Ta=25℃)
Parameter
Terminal Voltage
Power Dissipation1
Power Dissipation2
Power Dissipation3
Power Dissipation4
Operating temperature Range
Storage temperature Range
Junction Temperature
Symbol
VIN, CTL,SW1,SW2
EN1, EN2, PGOOD1, PGOOD2
Vo1, Vo2, MCTL1, MCTL2
FS1, FS2, FB1, FB2, ILIM1, ILIM2,
SS1, SS2, LG1, LG2, REF,REG2
BOOT1, BOOT2
BOOT1-SW1, BOOT2-SW2,
HG1-SW1, HG2-SW2
HG1
HG2
PGND1, PGND2
Pd1
Pd2
Pd3
Pd4
Topr
Tstg
Tjmax
Limits
30 *1*2
Unit
V
6 *1*2
V
REG1+0.3 *1
V
35 *1*2
V
7 *1*2
V
BOOT1+0.3 *1*2
BOOT2+0.3 *1*2
AGND±0.3 *1*2
0.38 *3
0.88 *4
3.26 *5
6
4.56 *
-20～+100
-55～+150
+150
V
V
V
W
W
W
W
℃
℃
℃
*1 Do not however exceed Pd.
*2 Instantaneous surge voltage, back electromotive force and voltage under less than 10% duty cycle.
*3 Reduced by 3.0mW for each increase in Ta of 1℃ over 25℃ (when don’t mounted on a heat radiation board )
*4 Reduced by 7.0mW for increase in Ta of 1℃ over 25℃. (when mounted on a board 74.2mm×74.2mm×1.6mm Glass-epoxy PCB which has 1 layer.
(Copper foil area : 20.2mm2)
*5 Reduced by 26.1mW for increase in Ta of 1℃ over 25℃. (when mounted on a board 74.2mm×74.2mm×1.6mm Glass-epoxy PCB which has 4 layers.
(1st and 4th copper foil area : 20.2mm2, 2nd and 3rd copper foil area : 5505mm2)
*6 Reduced by 36.5mW for increase in Ta of 1℃ over 25℃. (when mounted on a board 74.2mm×74.2mm×1.6mm Glass-epoxy PCB which has 4 layers.
(All copper foil area : 5505mm2)
●Operating conditions(Ta=25℃)
Parameter
Terminal Voltage
MIN ON TIME
★
Symbol
VIN
CTL
EN1, EN2, MCTL1, MCTL2
BOOT1, BOOT2
SW1, SW2
BOOT1-SW1, BOOT2-SW2, HG1-SW1, HG2-SW2
Vo1, Vo2, PGOOD1, PGOOD2
TONmin
MIN.
5.5
-0.3
-0.3
4.5
-0.3
-0.3
-0.3
-
MAX.
28
28
5.5
33
28
5.5
5.5
150
Unit
V
V
V
V
V
V
V
nsec
This product should not be used in a radioactive environment.
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2/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristics
(unless otherwise noted, Ta=25℃ VIN=12V, CTL=OPEN, EN1=EN2=5V, FS1=FS2=51kΩ)
Standard Value
Parameter
Symbol
Unit
Condition
250
μA
CTL=5V, EN1=EN2=0V
130
230
μA
Vo1=5V
6
12
18
μA
CTL=0V
VCTLL
-0.3
-
0.8
V
CTL High Voltage
VCTLH
2.3
-
28
V
CTL bias current
ICTL
-18
-12
-6
μA
EN Low Voltage
VENL
-0.3
-
0.8
V
EN High Voltage
VENH
2.3
-
5.5
V
EN bias current
IEN
-
3
6
μA
EN=3V
REG1 output voltage
VREG1
4.90
5.00
5.10
V
IREG1=1mA
Maximum current
IREG1
100
-
-
mA
IREG2=0mA
Line Regulation
Reg.l1
-
90
180
mV
VIN=5.5 to 25V
Load Regulation
Reg.L1
-
30
50
mV
IREG1=0 to 30mA
REG2 output voltage
VREG2
3.27
3.30
3.33
V
IREG2=1mA
Maximum current
IREG2
100
-
-
mA
IREG1=0mA
Line Regulation
Reg.l2
-
-
20
mV
VIN=5.5 to 25V
Load Regulation
Reg.L2
-
-
30
mV
IREG2=0 to 30mA
Input threshold voltage
REG1th
4.1
4.4
4.7
V
Input delay time
TREG1
1.5
3.0
6.0
ms
Switch resistance
RREG1
-
1.0
3.0
Ω
REG1_UVLO
3.9
4.2
4.5
V
dV_UVLO
50
100
200
mV
Feedback voltage1
VFB1
0.693
0.700
0.707
V
FB1 bias current
IFB1
-
0
1
μA
RDISOUT1
50
100
200
Ω
Feedback voltage2
VFB2
0.693
0.700
0.707
V
FB2 bias current
IFB2
-
0
1
μA
RDISOUT2
50
100
200
Ω
MIN.
TYP.
MAX.
ISTB
70
150
IIN
60
ISHD
CTL Low Voltage
VIN standby current
VIN bias current
VIN shut down mode current
CTL=0V
[5V linear regulator](VIN)
[3.3V linear regulator]
[5V linear regulator](Vo1)
Vo1: Sweep up
[Under Voltage lock out block]
REG1 threshold voltage
Hysteresis voltage
REG1: Sweep up
REG1, Sweep down
[Output voltage sense block]
Output discharge resistance1
Output discharge resistance2
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3/33
FB1=REF
FB2=REF
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristics – Continued
(unless otherwise noted, Ta=25℃ VIN=12V, CTL=OPEN, EN1=EN2=5V, FS1=FS2=51kΩ)
Standard Value
Parameter
Symbol
Unit
MIN.
TYP.
MAX.
Condition
[H3REG block]
Ontime1
TON1
0.760
0.910
1.060
μs
Vo1=5V
Ontime2
TON2
0.470
0.620
0.770
μs
Vo2=3.3V
Maximum On time 1
TONMAX1
2.5
5
10
μs
Vo1=5V
Maximum On time 2
TONMAX2
1.65
3.3
6.6
μs
Vo2=33V
Minimum Off time
TOFFMIN
-
0.2
0.4
μs
HG higher side ON resistor
HGHON
-
3.0
6.0
Ω
HG lower side ON resistor
HGLON
-
2.0
4.0
Ω
LG higher side ON resistor
LGHON
-
2.0
4.0
Ω
LG lower side ON resistor
LGLON
-
0.5
1.0
Ω
VOVP
0.77
(+10%)
0.84
(+20%)
0.91
(+30%)
V
dV_OVP
50
150
300
mV
SCP threshold voltage
VSCP
0.42
(-40%)
0.49
(-30%)
0.56
(-20%)
V
Delay time
TSCP
0.4
0.75
1.5
ms
dVSMAX
80
100
120
mV
VPGTHL
0.525
(-25%)
0.595
(-15%)
0.665
(-5%)
V
VPGL
-
0.1
0.2
V
Delay time
TPGOOD
0.4
0.75
1.5
ms
Power good leakage current
ILEAKPG
-2
0
2
μA
Charge current
ISS
1.5
2.3
3.1
μA
Standby voltage
VSS_STB
-
-
50
mV
VMCTL_L
-0.3
-
0.3
V
V
μA
[FET driver block]
[Over voltage protection block]
OVP threshold voltage
OVP Hysteresis
[Short circuit protection block]
[Current limit protection block]
Offset voltage
ILIM=100kΩ
[Power good block]
Power good low threshold
Power good low voltage
IPGOOD=1mA
VPGOOD=5V
[Soft start block]
[Mode control block]
MCTL Low voltage
MCTL High voltage
VMCTL_H
2.3
-
REG1
+0.3
MCTL bias current
IMCTL
8
16
24
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4/33
MCTL=5V
2010.03 - Rev.A
Technical Note
BD9528MUV
●Output condition table
Input
EN1
Low
Low
High
High
Low
Low
High
High
CTL
Low
Low
Low
Low
High
High
High
High
EN2
Low
High
Low
High
Low
High
Low
High
Output
REG2(3.3V)
DC/DC1
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
OFF
ON
OFF
ON
ON
ON
ON
REG1(5V)
OFF
OFF
OFF
OFF
ON
ON
ON
ON
DC/DC2
OFF
OFF
OFF
OFF
OFF
ON
OFF
ON
※ CTL pin is connected to VIN pin with 1MΩ resistor(pull up) internal IC.
※ EN pin is connected to AGND pin with 1MΩ resistor(pull down) internal IC.
3
1
2
31
32
22
23
PGND1
LG1
SW1
HG1
BOOT1
PGND2
LG2
SW2
HG2
BOOT2
VIN
VIN
Vo2
Adjustable
Vo1
Adjustable
●Block Diagram, Application circuit
24
26
25
REG1
REG1
REG1
REG1
CL2
SCP2
OVP2
AGND
Short through
Protection
Circuit
Short through
Protection
Circuit
13
CL1
SCP1
OVP1
FS1
FS2
UVLO
EN2
REF
FB2
11
Timer
REG1
PGOOD1
Power Good
Short Circuit Protect
20
EN1
FB1
Thermal
Protection
14
6
REF
12
SS1
19
ILIM2
ILIM1
17
3.3V
Reg
EN2
SW1
PGND1
MCTL
SLLM Mode Control
5V
Reg
Vo1
Reference
Block
REG1
PGND2
SW2
REF
8
CL1
Over Current
Protect
CL2
Over Current
Protect
SS2
SCP1
H3RegTM
Controller
Block
FS1
Timer
FS2
REF
H3RegTM
Controller
Block
SLLMTM
Block
MCTL
Over Voltage
Protect
OVP1
MCTL
TSD
Timer
Timer
Power Good
PGOOD2
SLLMTM
Block
Over Voltage
Protect
OVP2
SCP2
5
Short Circuit Protect
REG1
RFS1
15
10
EN1
4
Vo1
16
27
3.3V
18
MCTL2
REG2
REG2
5V
5.5～28V
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© 2010 ROHM Co., Ltd. All rights reserved.
28
1uF
REG1
29
MCTL1
30
REG1
VIN
9
VIN
7
CTL
Vo2
21
5/33
2010.03 - Rev.A
Technical Note
BD9528MUV
LG2
PGND2
MCTL1
ILIM1
SS1
PGOOD1
17
Input
25
16
26
15
27
14
28
13
FIN
MCTL2
FS1
FB1
AGND
29
12 REF
30
11
31
10
32
9
2
HG2
SW2
1
4
3
6
7
8
ILIM2
VIN
18
Vo2
REG1
19
SS2
REG2
20
5
PGOOD2
Vo1
21
EN2
LG1
22
BOOT2
PGND1
23
EN1
24
BOOT1
HG1
SW1
●Pin Configuration
MCTL1
MCTL2
Low
Low
High
High
Low
High
Low
High
Control Mode
SLLM
QLLM
Forced Continuous Mode
Forced Continuous Mode
※MCTL pin is connected to AGND pin with 500kΩ
resistor ( pull down) internal IC
FB2
FS2
CTL
●Pin Function Table
PIN No.
1
2
3
4
5
6
7
8
PIN name
SW2
HG2
BOOT2
EN2
PGOOD2
SS2
Vo2
ILIM2
9
CTL
10
11
12
13
14
15
16
17
18
19
20
FS2
FB2
REF
AGND
FB1
FS1
MCTL2
ILIM1
MCTL1
SS1
PGOOD1
21
EN1
22
23
24
25
26
27
28
29
30
31
32
reverse
BOOT1
HG1
SW1
PGND1
LG1
Vo1
REG2
REG1
VIN
LG2
PGND2
FIN
PIN Function
Highside FET source pin 2
Highside FET gate drive pin 2
HG Driver power supply pin 2
Vo2 ON/OFF pin (High=ON, Low,OPEN=OFF)
Vo2 Power Good Open Drain Output pin
Vo2 Soft start pin
Vo2 Output voltage sense pin
OCP setting pin 2
Linear regulator ON/OFF pin
(High,OPEN=ON, Low=OFF)
Input pin for setting Vo2 frequency
Vo2 output voltage feedback pin
Output voltage setting pin
Input pin Ground
Vo1 output voltage feedback pin
Input pin for setting Vo1 frequency
Mode switch pin 2 ( OPEN = L )
OCP setting pin 1
Mode switch pin 1 ( OPEN = L )
Vo1 Soft start pin
Vo1 Power Good Open Drain Output pin
Vo1 ON/OFF pin
(High=ON, Low,OPEN=OFF)
HG Driver power supply pin
Highside FET gate drive pin 1
Highside FET source pin 1
Lowside FET source pin 1
Lowside FET gate drive pin 1
Vo1 Output voltage sense pin
3.3V Linear regulator output pin
5V Linear regulator output pin
Power supply input pin
Lowside FET gate drive pin 2
Lowside FET source pin 2
Exposed Pad1, connect to GND
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6/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristic curves (Reference data)
HG
10V/div
SW
10V/div
HG
10V/div
SW
10V/div
LG
5V/div
LG
5V/div
2us
2us
Fig.1 Switching Waveform
(Vo=5V, PWM, Io=0A)
Fig.2 Switching Waveform
(Vo=5V, PWM, Io=8A)
HG
10V/div
SW
10V/div
10us
2us
10us
HG
10V/div
SW
10V/div
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© 2010 ROHM Co., Ltd. All rights reserved.
10us
Fig.11 Switching Waveform
(Vo=1V, QLLM, Io=0A)
7/33
LG
5V/div
LG
5V/div
HG
10V/div
SW
10V/div
2us
LG
5V/div
Fig.9 Switching Waveform
(Vo=1V, PWM, Io=0A)
HG
10V/div
SW
10V/div
LG
5V/div
Fig.10 Switching Waveform
(Vo=1V, PWM, Io=8A)
2us
Fig.6 Switching Waveform
(Vo=3.3V, PWM, Io=8A)
Fig.8 Switching Waveform
(Vo=3.3V, SLLM, Io=0A)
Fig.7 Switching Waveform
(Vo=3.3V, QLLM, Io=0A)
2us
LG
5V/div
HG
10V/div
SW
10V/div
HG
10V/div
SW
10V/div
LG
5V/div
LG
5V/div
Fig.3 Switching Waveform
(Vo=5V, QLLM, Io=0A)
Fig.5 Switching Waveform
(Vo=3.3V, PWM, Io=0A)
HG
10V/div
SW
10V/div
10us
10us
HG
10V/div
SW
10V/div
LG
5V/div
Fig.4 Switching Waveform
(Vo=5V, SLLM, Io=0A)
HG
10V/div
SW
10V/div
LG
5V/div
HG
10V/div
SW
10V/div
10us
LG
5V/div
Fig.12 Switching Waveform
(Vo=1V, SLLM, Io=0A)
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristic curves (Reference data) – Continued
100
100
80
80
100
80
7V
7V
12V
21V
40
12V
60
12V
40
η[%]
60
η[%]
η[%]
7V
21V
20
20
1
10
100
Io[mA]
1000
21V
40
20
0
0
60
1
10000
10
Fig.13 Efficiency
(Vo=5V, PWM)
100
Io[mA]
1000
0
10000
1
Fig.14 Efficiency
(Vo=5V, QLLM)
100
10
100
Io[mA]
1000
10000
Fig.15 Efficiency
(Vo=5V, SLLM)
100
100
5V
80
7V
η[%]
7V
21V
40
12V
60
60
21V
40
20
20
0
0
1
10
100
Io[mA]
1000
Fig.16 Efficiency
(Vo=3.3V, PWM)
10
100
Io[mA]
1000
10000
1
12V
7V
η[%]
20
12V
21V
40
1
10
100
Io[mA]
1000
10000
Fig.19 Efficiency
(Vo=1V, PWM)
1
10
100
Io[mA]
20us
1000
10000
Vo
100mV/div
1
10
100
Io[mA]
1000
10000
20us
Vo
100mV/div
IL
5A/div
Io
5A/div
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21V
40
Fig.21 Efficiency
(Vo=1V, SLLM)
20us
© 2010 ROHM Co., Ltd. All rights reserved.
12V
60
0
0
Fig.20 Efficiency
(Vo=1V, QLLM)
Fig.22 Transient Response
(Vo=5V, PWM, Io=0→8A)
10000
20
20
0
1000
7V
80
60
21V
40
100
Io[mA]
100
80
7V
10
Fig.18 Efficiency
(Vo=3.3V, SLLM)
100
60
21V
Fig.17 Efficiency
(Vo=3.3V, QLLM)
100
80
40
0
1
10000
12V
20
η[%]
η[%]
60
η[%]
80
7V
12V
η[%]
80
Vo
100mV/div
IL
5A/div
Io
5A/div
IL
5A/div
Io
5A/div
Fig.23 Transient Response
(Vo=5V, PWM, Io=8→0A)
8/33
Fig.24 Transient Response
(Vo=3.3V, PWM, Io=0→8A)
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristic curves (Reference data) – Continued
20us
20us
Vo
100mV/div
Vo
100mV/div
Fig.26 Transient Response
(Vo=1V, PWM, Io=0→8A)
Vo
50mV/div
Fig.27 Transient Response
(Vo=1V, PWM, Io=8→0A)
2us
10us
Fig.29 Output Voltage
(Vo=5V, PWM, Io=8A)
Fig.30 Output Voltage
(Vo=5V, QLLM, Io=0A)
Vo
50mV/div
Vo
50mV/div
2us
Fig.31 Output Voltage
(Vo=5V, SLLM, Io=0A)
2us
Fig.32 Output Voltage
(Vo=3.3V, PWM, Io=0A)
Fig.33 Output Voltage
(Vo=3.3V, PWM, Io=8A)
Vo
50mV/div
Fig.34 Output Voltage
(Vo=3.3V, QLLM, Io=0A)
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© 2010 ROHM Co., Ltd. All rights reserved.
Vo
50mV/div
2us
Vo
50mV/div
10us
2us
Fig.35 Output Voltage
(Vo=3.3V, SLLM, Io=0A)
9/33
IL
5A/div
Io
5A/div
Vo
50mV/div
Vo
50mV/div
2us
Fig.28 Output Voltage
(Vo=5V, PWM, Io=0A)
Vo
100mV/div
IL
5A/div
Io
5A/div
IL
5A/div
Io
5A/div
Fig.25 Transient Response
(Vo=3.3V, PWM, Io=8→0A)
20us
Vo
50mV/div
2us
Fig.36 Output Voltage
(Vo=1V, PWM, Io=0A)
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristic curves (Reference data) – Continued
Vo
50mV/div
Vo
50mV/div
2us
Vo
50mV/div
10us
Fig.37 Output Voltage
(Vo=1V, PWM, Io=8A)
2us
Fig.38 Output Voltage
(Vo=1V, QLLM, Io=0A)
Fig.39 Output Voltage
(Vo=1V, SLLM, Io=0A)
EN1
5V/div
EN1
5V/div
EN1
5V/div
Vo1
2V/div
Vo1
2V/div
Vo1
2V/div
EN2
5V/div
EN2
5V/div
EN2
5V/div
Vo2
2V/div
Vo2
2V/div
Vo2
2V/div
Fig.40 Wake up waveform
(EN1=EN2)
Fig.42Wake up waveform
(EN1→EN2)
Fig.41 Wake up waveform
(EN2→EN1)
IOUT-frequency (VOUT=5V, R(FS)=68kΩ)
frequency [kHz]
PGOOD1
2V/div
EN2
5V/div
500
450
450
400
VIN=7.5V
VIN=12V
VIN=18V
350
PGOOD2
2V/div
IOUT-frequency (VOUT=5V, R(FS)=68kΩ)
500
frequency [kHz]
EN1
5V/div
400
VIN=7.5V
VIN=12V
VIN=18V
350
300
300
0
1
2
3
4
5
6
7
0
1
2
3
IOUT [A]
700
2.5
5
6
7
Fig.45 Io-frequency
(Vo=3.3V, PWM, RFS=68kΩ)
Fig.44 Io-frequency
(Vo=5V, PWM, RFS=68kΩ)
Fig.43Wake up waveform
(EN1/2→PGOOD1/2)
4
IOUT [A]
5.500
5.000
600
VOUT=5V
500
frequency [kHz]
ONTIME [usec]
VOUT=3.3V
1.5
1
VOUT=5V
4.500
VOUT=3.3V
4.000
VIN=7.5V(-5℃）
VIN=21V（-5℃）
VIN=7.5V(75℃）
3.500
400
VOUT [V]
2
300
VIN=21V（75℃）
3.000
2.500
2.000
200
1.500
0.5
1.000
100
0.500
0
0
0
50
100
150
RFS [kΩ]
Fig.46 FS-ONTIME
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0.000
0
50
100
RFS [kΩ]
Fig.47 FS-frequency
10/33
150
0
2
4
6
8
10
12
14
16
IOUT [A]
Fig.48 Ta-IOCP
(Vo=5V)
2010.03 - Rev.A
Technical Note
BD9528MUV
●Electrical characteristic curves (Reference data) – Continued
IOUT - REG2 voltage
IOUT - REG1 voltage
3.500
3.000
5.1
3.4
5
3.3
REG1 voltage [V]
VIN=21V（-5℃）
VOUT [V]
VIN=7.5V(75℃）
VIN=21V（75℃）
2.000
1.500
REG2 voltage [V]
VIN=7.5V(-5℃）
2.500
4.9
4.8
4.7
1.000
3.2
3.1
3
2.9
4.6
0.500
2.8
4.5
0.000
0
2
4
6
8
10
12
14
16
IOUT [A]
Fig.49 Ta-IOCP
(Vo=3.3V)
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0
50
100
150
200
IOUT [mA]
Fig.50 IREG1-REG1
11/33
250
0
50
100
150
200
250
IOUT [mA]
Fig.51 IREG2-REG2
2010.03 - Rev.A
Technical Note
BD9528MUV
●Pin Descriptions
・VIN (30 pin)
This is the main power supply pin. The input supply voltage range is 5.5V to 25V. The duty cycle of BD9528MUV is
determined by input voltage and control output voltage. Therefore, when VIN voltage fluctuated, the output voltage also
becomes unstable. Since VIN line is also the input voltage of switching regulator, stability depends on the impedance of the
voltage supply. It is recommended to establish bypass capacitor and CR filter suitable for the actual application.
・CTL (9 pin)
When CTL pin voltage is at least 2.3V, the status of the linear regulator output becomes active (REG1=5V, REG2=3.3V).
Conversely, the status switches off when CTL pin voltage goes lower than 0.8V. The switching regulator doesn’t become
active when the status of CTL pin is low, if the status of EN pin is high.
(※CTL pin is connected to VIN pin with 1MΩ resistor(pull up) internal IC)
・EN1, 2 (21 pin, 4 pin)
When EN pin voltage is at least 2.3V, the status of the switching regulator becomes active. Conversely, the status switches
off when EN pin voltage goes lower than 0.8V.
(※EN pin is connected to AGND pin with 1MΩ resistor(pull down) internal IC)
・REG1 (29 pin)
This is the output pin for 5V linear regulator and also active in power supply for driver and control circuit of the inside. The
standby function for REG1 is determined by CTL pin. The voltage is 5V, with 100mA current ability. It is recommended that
a 10μF capacitor (X5R or X7R) be established between REG1 and GND.
・REG2 (28 pin)
This is the output pin for 3.3V linear regulator. The standby function for REG2 is determined by CTL. The voltage is 3.3V,
with 50mA current ability. It is recommended that a 10μF capacitor (X5R or X7R) be established between REG2 and GND.
・REF (12 pin)
This is the setting pin for output voltage of switching regulator. This IC controls the voltage in the status of REF≒FB.
・FB 1, 2 (14 pin, 11 pin)
This is the feedback pin from the output of switching regulator. This IC controls the voltage in the status of REF≒FB.
・Vo1 (27 pin)
This is the output discharge pin, and output voltage feedback pin for frequency setting. When the voltage is beyond 4.4V
from the external power supply during operation, it supplies REG1.
・Vo2 (7 pin)
This is the output discharge pin, and output voltage feedback pin for frequency setting.
・SS1, 2 (19 pin, 6 pin)
This is the setting pin for soft start. The rising time is determined by the capacitor connected between SS and GND, and
the fixed current inside IC after it is the status of low in standby mode. It controls the output voltage till SS voltage catch up
the REF pin to become the SS terminal voltage.
・FS1, 2 (15 pin, 10 pin)
This is the input pin for setting the frequency. It is available to set it in frequency range is 200KHz to 500kHz.
・ILIM1, 2 (17 pin, 8 pin)
BD9528MUV detects voltage differential between SW and PGND, and set OCP. OCP setting current value is determined
by the resistance value of ILIM pin. FET of various Ron is available.
・PGOOD 1, 2 (20 pin, 5 pin)
This is the open drain pin for deciding the output of switching regulator.
・MCTL1, 2 (18 pin, 16 pin)
This is the switching shift pin for SLLM (Simple Light Load Mode). MCTL pin is at low level when it goes lower than 0.8V,
and at high level when it goes higher than 2.3V.
(※MCTL pin is connected to AGND pin with 500kΩ resistor(pull down) internal IC)
・AGND (13 pin)
This is the ground pin.
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2010.03 - Rev.A
Technical Note
BD9528MUV
・BOOT1, 2 (22 pin, 3 pin)
This is the power supply pin for high side FET driver. The maximum voltage range to GND pin is to 35V, to SW pin is to 7V.
In switching operations, the voltage swings from (VIN+REG1) to REG1 by BOOT pin operation.
・HG1, 2 (23 pin, 2 pin)
This is the highside FET gate drive pin. It is operated in switching between BOOT to SW. In case the output MOS is 3ohm
/the status of Hi, 2ohm/the status of Low, it is operated hi-side FET gate in high speed.
・SW1, 2 (24 pin, 1 pin)
This is the ground pin for high side FET drive. The maximum voltage range to GND pin is to 30V. Switching operation
swings from the status of BOOT to the status of GND.
・LG1, 2 (26 pin, 31 pin)
This is the lowside FET gate drive pin. It is operated in switching between REG1 to PGND. In case the output MOS is
2ohm /the status of Hi, 0.5ohm/the status of Low, it is operated low-side FET gate in high speed.
・PGND1, 2 (25 pin, 32 pin)
This is the ground pin for low side FET drive.
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13/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Explanation of Operation
3
The BD9528MUV is a 2ch synchronous buck regulator controller incorporating ROHM’s proprietary H REG CONTROLLA
control system. Because controlling of output voltage by a comparator, high response is realized with not relying on the
switching frequency. And, when VOUT drops due to a rapid load change, the system quickly restores VOUT by extending
the TON time interval. Thus, it serves to improve the regulator’s transient response. Activating the Light Load Mode will also
exercise Simple Light Load Mode (SLLM) control when the load is light, to further increase efficiency.
VIN
H3RegTM control
Comparator for
output voltage
control
Vout/Vin
Circuit
FB
HG
A
Driver
B
VOU
T
SW
LG
Internal
reference
voltage
REF
Transient
Circuit
(Normal operation)
FB
When FB falls to a reference voltage (REF), the drop is
detected, activating the H3REG CONTROLLA
system.<Route A>
（ tON=
）
VOUT × 1 [sec]・・・(1)
REF
HG
VIN
f
HG output is determined by the formula above.
After the status of HG is OFF, LG go on outputting until
output voltage become FB=REF.
LG
(VOUT drops due to a rapid load change)
FB
When VOUT drops due to a rapid load change, and the
voltage remains below reference voltage after the
programmed tON time interval has elapsed (Output of a
comparator for output voltage control =H), the system
quickly restores VOUT by extending the tON time,
improving the transient response.<Route B> After VOUT
restores (FB=REF), HG turns to be OFF, and it goes back
to a normal operation.
REF
tON +α
Io
HG
LG
(when VIN drops)
VIN
tON1
tON2
tON3
tON4
tON4+α
H3RegTM
HG
tOFF1
t OFF2
t OFF3
tOFF4=tOFF3
tOFF4=t OFF3
LG
FB
REF
Output voltage drops
FB=REF
If VIN voltage drops because of the battery voltage fall, ontime tON and offtime tOFF is determined by the following formula:
tON=VOUT/VIN×I/f and tOFF=(VIN-VOUT)/VIN×f so that tON lengthen and tOFF shorten to keep output voltage constant. However,
if VIN still drops and tOFF equals to tminoff (tminoff：Minimum OFF time, regulated inside IC) , because tOFF cannot shorten any
3
TM
more, as a result output voltage drops. In H Reg system, lengthening tON time than regulated tON (lengthen tON time until FB＞REF)
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14/33
2010.03 - Rev.A
Technical Note
BD9528MUV
enables to operate stable not to drop the output voltage even if VIN turns to be low. With the reason above, it is suitable for
2-cell battery.
Light Load Control
(SLLM)
FB
In SLLM, when the status of LG is OFF and the coil
current is within 0A (it flows to SW from VOUT.), SLLM
function is operated to prevent output next HG. The
status of HG is ON, when FB falls below reference voltage
again.
REF
HG
LG
0A
(QLLM)
FB
REF
In QLLM, when the status of LG is OFF and the coil
current is within 0A (it flows to SW from VOUT.), QLLM
function is operated to prevent output next HG.
Then, FB falls below the output programmed voltage
within the programmed time (typ=40μs), the status of HG
is ON. In case FB doesn’t fall in the programmed time, the
status of LG is ON forcedly and VOUT falls. As a result,
he status of next HG is ON.
HG
LG
0A
MCTL1
L
L
H
3
MCTL2
L
H
X
Control mode
SLLM
QLLM
PWM
Running
PWM
PWM
PWM
The BD9528MUV operates in PWM mode until SS pin
reaches cramp voltage (2.5V), regardless of the control
mode setting, in order to operate stable during the
operation. .
TM
＊Attention: H Reg CONTROLLA monitors the supplying current from
capacitor to load, using the ESR of output capacitor, and realize
the rapid response. Bypass capacitor used at each load (Ex.
Ceramic capacitor) exercises the effect with connecting to each
load side. Do not put a ceramic capacitor on COUT side of power
supply.
● Timing Chart
• Soft Start Function
COUT
Load
Soft start is exercised with the EN pin set high. Current
control takes effect at startup, enabling a moderate
output voltage “ramping start.” Soft start timing and
incoming current are calculated with formulas (2) and
(3) below.
EN
TSS
SS
Soft start time
Tss=
VOUT
REF×Css
[sec] ・・・(2)
2.3μA(typ)
Incoming current
IIN=
IIN
Co×VOUT
Tss
[A] ・・・(3)
(Css: Soft start capacitor; Co: Output capacitor)
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15/33
2010.03 - Rev.A
Technical Note
BD9528MUV
Notes when waking up with CTL pin or VIN pin
If EN pin is High or short (or pull up resistor) to REG1 pin, IC starts up by switching CTL pin, the IC might fail to start up (SCP
function) with the reason below, please be careful of SS pin and REF pin capacitor capacity.
REG1 REG2
FB
VIN
CTL
Inner
reference
circuit
BG
SCP circuit
Delay
SCP
REF
SCP_REF
1ms(typ.)
SCP
PWM
SS
(Switching control signal)
CTL
(VIN)
REG1
REG2
REG1, REG2
REG1 UVLO cancellation
BG
0.49V(typ)
SCP_REF
(REF start-up time＜SS start-up time)
SCP function masked SCP mask cancellation
FB starts up as SS reference
REF
SS
FB
SS
FB
(REF start-up time＞SS start-up time)
REF
FB
SCP mask
SCP mask cancellation
SS
SCP function is masked until SS pin reaches
cramp voltage (2.5V).
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16/33
FB starts up as REF reference
After the end of SS wake-up,
within SCP delay time (1ms), if
REF voltage does not reach
SCP_REF(0.49V), SCP turns
ON and shut down.
2010.03 - Rev.A
Technical Note
BD9528MUV
●Output Discharge
It will be available to use if connecting VOUT pin to DC/DC output.
(Total about 100Ω) . Discharge function operates when ①EN=’L’
②UVLO=ON(If input voltage is low) ③SCP Latch time ④TSD=ON.
The function at output discharge time is shown as left.
VIN,CTL
EN
(1)during EN=’H’→‘L’
If EN pin voltage is below than EN threshold voltage, output
discharge function is operated, and discharge output capacitor
charge.
VOUT
VIN, CTL
REG1
VOUT
The efficiency of
VIN voltage drop
Output Discharge
Output Hi-Z
UVLO ON
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(2) during VIIN=CTL=H→0V
① IC is in normal operation until REG1 voltage becomes lower than
UVLO voltage. However, because VIN voltage also becomes low,
output voltage will drop, too.
② If REG1 voltage reaches the UVLO voltage, output discharge
function is operated, and discharge output capacitor charge.
③ In addition, if REG1 voltage drops, inner IC logic cannot operate, so
that output discharge function does not work, and becomes output
Hi-z. （In case, FB has resistor against GND, discharge at the
resistor.）
17/33
2010.03 - Rev.A
Technical Note
BD9528MUV
・Timer Latch Type Short Circuit Protection
FB
Short protection kicks in when output falls to or below
REF X 0.7.
When the programmed time period elapses, output is
latched OFF to prevent destruction of the IC. (HG=Low,
LG=Low) Output voltage can be restored either by
reconnecting the EN pin or disabling UVLO.
REF×0.7
1ms(typ)
SCP
EN / UVLO
・Over Voltage Protection
REF×1.2
FB
When output rise to or above REF×1.2 (typ), output
over voltage protection is exercised, and low side FET
goes up maximum for reducing output.(LG=High,
HG=Low).When output falls, output voltage can be
restored., and go back to the normal operation.
HG
LG
Switching
・Over current protection circuit
tON
tON
tON
tON
During the normal operation, when FB becomes less
than REF, HG becomes High during the time tON, and
after HG becomes OFF, it output LG.
However, when inductor current exceeds ILIMIT threshold,
next HG pulse doesn’t pulsate until it is lower than ILIMIT
level.
HG
LG
IL
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18/33
2010.03 - Rev.A
Technical Note
BD9528MUV
● External Component Selection
1. Inductor (L) selection
The inductor value is a major influence on the output ripple
current. As formula (4) below indicates, the greater the inductor or
the switching frequency, the lower the ripple current.
(VIN-VOUT)×VOUT
[A]・・・(4)
ΔIL=
L×VIN×f
The proper output ripple current setting is about 30% of maximum
output current.
ΔIL=0.3×IOUTmax. [A]・・・(5)
ΔIL
VIN
IL
VOUT
(VIN-VOUT)×VOUT
L
L=
Co
ΔIL×VIN×f
[H]・・・(6)
(ΔIL: output ripple current; f: switch frequency)
Output ripple current
※Passing a current larger than the inductor’s rated current will cause magnetic saturation in the inductor and decrease
system efficiency. In selecting the inductor, be sure to allow enough margin to assure that peak current does not exceed the
inductor rated current value.
※To minimize possible inductor damage and maximize efficiency, choose a inductor with a low (DCR, ACR) resistance.
2.Output Capacitor (CO) Selection
VIN
When determining the proper output capacitor, be sure to factor in the
equivalent series resistance required to smooth out ripple volume and maintain
a stable output voltage range.
Output ripple voltage is determined as in formula (7) below.
VOUT
L
ΔVOUT=ΔIL×ESR+ESL×ΔIL/TON・・・(7)
ESR
Co
(ΔIL: Output ripple current; ESR: CO equivalent series resistance)
※ In selecting a capacitor, make sure the capacitor rating allows sufficient
margin relative to output voltage. Note that a lower ESR can minimize output
ripple voltage.
Output Capacitor
Please give due consideration to the conditions in formula (8) below for output capacity, bear in mind that output rise time
must be established within the soft start time frame. Capacitor for bypass capacitor is connected to Load side which connect
to output in output capacitor capacity (CEXT, figure above). Please set the soft start time or over current detecting value,
regarding these capacities.
Co≦
Tss×(Limit-IOUT)
VOUT
・・・(8)
Tss: Soft start time
Limit: Over current detection
Note: Improper capacitor may cause startup malfunctions.
3. Input Capacitor (Cin) Selection
The input capacitor selected must have low enough ESR resistance to fully
support large ripple output, in order to prevent extreme over current. The
formula for ripple current IRMS is given in (9) below.
VIN
Cin
VOUT
L
IRMS=IOUT×
√VIN(VIN-VOUT)
VIN
Co
[A]・・・(9)
IOUT
Where VIN=2×VOUT, IRMS=
2
Input Capacitor
A low ESR capacitor is recommended to reduce ESR loss and maximize efficiency.
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19/33
2010.03 - Rev.A
Technical Note
BD9528MUV
4. MOSFET Selection
MOSFET may cause the loss as below, so please select proper FET for each.
＜Loss on the main MOSFET＞
VIN
Pmain=PRON+PGATE+PTRAN
main switch
VOUT
=
VIN
VOUT
L
×RON×IOUT2+Ciss×f×VDD+
2
VIN ×Crss×IOUT×f
IDRIVE
・・・(10)
(Ron: On-resistance of FET; Ciss: FET gate capacitance;
f: Switching frequency Crss: FET inverse transfer function;
IDRIVE: Gate peak current)
Co
＜Loss on the synchronous MOSFET＞
synchronous switch
Psyn=PRON+PGATE
=
VIN-VOUT
VIN
×RON×IOUT2+Ciss×f×VDD ・・・(11)
5. Setting output voltage
This IC is operated that output voltage is REF≒FB.
And it is operated that output voltage is feed back to FB pin.
<Output Voltage>
V OUT 
(R1  R2)
 REF(0.7V)
R2
⊿V OUT  ⊿I Ripple  ESR
⊿I Ripple  (V IN  V OUT ) 
※(Notice)

(⊿VOUT:Output ripple voltage)
⊿V OUT (⊿Iripple: ripple current of coil, ESR: ESR of output capacitor)
2
(L:inductance[H] f:switching frequency[Hz])
1
V OUT
(L  V IN  f)
Please set ⊿VOUT more than 20mV
Ex. VIN=20V,VOUT=5V,f=300kHz,L=2.5uH,ESR=20mΩ,R1=56KΩ,R2=9.1kΩ
-6
3
⊿Iripple=(20V-5V)×5V/(2.5×10 H×20V×300×10 Hz)=5[A]
-3
⊿VOUT=5A×20×10 Ω=0.1[V]
VOUT=(51kΩ+9.1kΩ)/9.1kΩ+1/2×0.1V=5.057[V]
Select (R1 + R2) under 100KΩ(recommend)
VIN
H3REG
CONTROLLA
VIN
R
Q
SLLM
Output voltage
Driver
S
SLLM
Circuit
FB
VIN
R1
R2
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20/33
2010.03 - Rev.A
Technical Note
BD9528MUV
6. Setting over current protection
VIN
Detecting the ON resistance (between SW and PGND
voltage) of MOSFET at low side, it set the over current
voltage protection.
Over current reference voltage (ILIM_ref) is determined as in
formula(12) below.
L
VOUT
SW
Co
10×103
PGND
RILIM
ILIM_REF =
[A]・・・(12)
RILIM[KΩ]×RON[mΩ]
(RILIM: Resistance for setting of over current voltage protection value[kΩ]
RON: Low side ON resistance value of FET[mΩ])
However, the value, which set the over current protection actually, is
determined by the formula (13) below.
1
△IL
Iocp= ILIM_ref +
2
1
I × Vo ・・・(13)
× VIN - Vo ×
= ILIM_ref +
VIN
f
2
L
(△IL：Coil ripple current[A], VIN：Input voltage[V], Vo：Output voltage[V]
ｆ：Switching frequency[HZ], L：Coil inductance[H])
Coil current
Iocp
ILIM_ref
(Example)
If load current 5A want to be realized with VIN=6～19V, VOUT=5V, ｆ=400kHZ, L=2.5uH, RON=20mΩ, the formula would be
below.
10k
1
I × Vo ＞ 5
× VIN - Vo ×
+
Iocp=
RILIM[kΩ] ×RON[mΩ]
VIN
2
f
L
When VIN=6V, Iocp will be minimum(this is because the ripple current is also minimum) so that if each condition is input,
the formula will be the following: RILIM＜109.1[kΩ].
※To design the actual board, please consider enough margin for FET ON resistor dispersion, Coil inductor dispersion, IC over
current reference value dispersion, frequency dispersion.
7. Relation between output voltage and TON time
The BD9528MUV, both 1ch and 2ch, are high efficiency synchronous regulator controller with frequency variable.
TON time varies with Input voltage [VIN], output voltage [VOUT], and RFS of FS pin resistance.
TON time is calculated with the following formula:
VOUT・RFS
[nsec]・・・(14)
TON =k
VIN
From TON time above, frequency on application condition is following:
VOUT
1
×
[kHz]・・・(15)
VIN
Ton
However, real-life considerations (such as the external MOSFET gate capacitor and switching speed) must be factored in
as they affect the overall switching rise and fall time, so please confirm in reality by the instrument.
Frequency =
3.5
VIN=7V
VIN=7V
VIN=12V
VIN=12V
2
ontime[us]
2
1.5
0.9
VIN=7V
0.8
VIN=21V
VIN=12V
0.7
ontime[us]
VIN=21V
2.5
ontime[us]
1
2.5
3
1.5
1
VIN=21V
0.6
0.5
0.4
0.3
1
0.2
0.5
0.5
0.1
0
0
0
0
20
40
60
80
100
120
RFS[kΩ]
RFS – ontime(VOUT=5V)
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0
20
40
60
RFS[kΩ]
80
100
RFS – ontime(VOUT=3.3V)
21/33
120
0
20
40
60
RFS[kΩ]
80
100
120
RFS – ontime(VOUT=1V)
2010.03 - Rev.A
Technical Note
BD9528MUV
8. Relation between output voltage and frequency
Because the BD9528MUV is TON time focused regulator controller, if output current is up, switching loss of Coil, MOSFET
and output capacitor will increase, and frequency will be fast.
Loss of each Coil, MOSFET and output capacitor are below.
① Coil loss
2
= IOUT × DCR
VOUT
② MOSFET(High Side) loss
③ MOSFET(Low Side) loss
2
= IOUT × Ronh ×
2
= IOUT × Ronl × (1-
VIN
VOUT
)
VIN
(Ronh : ON resistance of high side MOSFET, Ronl : ON resistance of low side MOSFET,
ESR : Output capacitor equivalent cascade resistance)
Regarding those loss above and frequency formula, it is determined below.
T (=1/Freq) =
VIN × IOUT × TON
・・・(16)
VOUT × IOUT + ① + ② + ③
However, real-life considerations (such as parasitic resistance element of Layout pattern) must be factored in as they affect
the loss, please confirm in reality by the instrument.
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22/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●I/O Equivalent Circuit
1, 24pin (SW2, SW1)
BOOT
2, 23pin (HG2, HG1)
BOOT
3, 22pin (BOOT2, BOOT1)
BOOT
HG
HG
SW
SW
4, 21pin (EN2, EN1)
5, 20pin (PGOOD2, PGOOD1)
6, 19pin (SS2, SS1)
REG1
12pin (REF)
11, 14pin (FB2, FB1)
10, 15pin (FS2, FS1)
9pin (CTL)
26, 31pin (LG1, LG2)
REG1
16, 18pin (MCTL2, MCTL1)
VIN
REG1
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© 2010 ROHM Co., Ltd. All rights reserved.
23/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●I/O Equivalent Circuit
7, 27pin (Vo2, Vo1)
28pin (REG2)
29pin (REG1)
REG1
VIN
30pin (VIN)
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© 2010 ROHM Co., Ltd. All rights reserved.
VIN
8, 17pin (ILIM2, ILIM1)
24/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Evaluation Board Circuit (Vo1=5V/8A f1=300kHz Vo2=3.3V/8A f2=300kHz)
VIN
7V～28V
R1
CTL
VIN
CTL
VIN
BD9528MUV
30
VIN
C1
BOOT1
R2
9
EN1
HG1
R3
REG1
21
EN1
4
EN2
SW1
R9
C9
CTL
EN1
REG1
22
23
C10
C7
R10
Q2
VO1
SW1
L1
24
EN2
EN2
VIN
C13
D1
R4
REG1
5V
29
LG1
PGND1
28
C14
C15
C16 C17
C23
R17
R11
Q1
REG1
C2
REG2
3.3V
26
REG2
FB1
25
14
C24
C3
R18
12
REF
Vo1
C4
19
SS1
6
SS2
27
VIN
BOOT2
3
HG2
2
SW2
1
LG2
31
PGND2
32
FB2
11
R12
C8
R13
C5
C6
17
ILIM1
C12
VO2
L2
C18
R14
ILIM2
R6
15
C11
Q4
SW2
R5
8
VIN
Q3
D2
R19
C19
C20
C21 C22
C25
C26
FS1
R20
R7
Vo2
10
REG1
PGOOD1
R15
R8
MCTL1
7
FS2
PGOOD1
18
20
REG1
PGOOD2
MCTL1
R16
R28
PGOOD2
5
MCTL2
16
MCTL2 AGND
R27
DESIGNATION
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R13
R14
R15
R16
R17
R18
R19
R20
R27
R28
C1
C2
C3
C4
C5
C6
RATING
0Ω
0Ω
0Ω
68kΩ
68kΩ
75kΩ
75kΩ
0Ω
0Ω
0Ω
0Ω
0Ω
0Ω
100kΩ
100kΩ
91kΩ
15kΩ
30kΩ
8.2kΩ
0Ω
0Ω
10uF(25V)
10uF(6.3V)
10uF(6.3V)
0.1uF(6.3V)
2200pF(50V)
2200pF(50V)
13
PART No.
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
CM32X7R106M25A
GRM21BB10J106KD
GRM21BB10J106KD
GRM21BB10J104KD
GRM188B11H102KD
GRM188B11H102KD
www.rohm.com
© 2010 ROHM Co., Ltd. All rights reserved.
COMPANY
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
KYOCERA
MURATA
MURATA
MURATA
MURATA
MURATA
DESIGNATION
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C26
D1
D2
L1
L2
Q1
Q2
Q3
Q4
U1
25/33
RATING
0.47uF(10V)
0.47uF(10V)
10uF(25V)
10uF(25V)
330uF
330uF
Diode
Diode
2.5uH
2.5uH
FET
FET
FET
FET
-
PART No.
GRM188B11A474KD
GRM188B11A474KD
CM32XR7106M25A
CM32XR7106M25A
6TPE330MI
6TPE330MI
RSX501L-20
RSX501L-20
CDEP105NP-2R5MC-32
CDEP105NP-2R5MC-32
uPA2709
uPA2709
uPA2709
uPA2709
BD9528MUV
COMPANY
MURATA
MURATA
KYOCERA
KYOCERA
SANYO
SANYO
ROHM
ROHM
Sumida
Sumida
NEC
NEC
NEC
NEC
ROHM
2010.03 - Rev.A
Technical Note
BD9528MUV
●Evaluation Board Circuit for Low input voltage(Vo1=5V/8A f1=300kHz Vo2=3.3V/8A f2=300kHz)
VIN
6V～28V
R1
CTL
VIN
CTL
VIN
BD9528MUV
30
VIN
C1
BOOT1
R2
9
EN1
HG1
R3
REG1
21
EN1
4
EN2
SW1
R9
C9
CTL
EN1
REG1
22
23
C10
C7
R10
Q2
VO1
SW1
L1
24
EN2
EN2
VIN
C13
D1
R4
REG1
5V
29
LG1
PGND1
28
C14
C15
C16 C17
C23
R17
R11
Q1
REG1
C2
REG2
3.3V
26
REG2
FB1
25
14
C24
C3
R18
12
REF
Vo1
C4
19
SS1
6
SS2
27
VIN
BOOT2
3
HG2
2
SW2
1
LG2
31
PGND2
32
FB2
11
R12
C8
R13
C5
C6
17
ILIM1
C12
VO2
L2
C18
R14
ILIM2
R6
15
C11
Q4
SW2
R5
8
VIN
Q3
D2
R19
C19
C20
C21 C22
C25
C26
FS1
R20
R7
Vo2
10
REG1
PGOOD1
R15
R8
MCTL1
7
FS2
PGOOD1
18
20
REG1
PGOOD2
MCTL1
R16
R28
PGOOD2
5
MCTL2
16
MCTL2 AGND
R27
DESIGNATION
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R13
R14
R15
R16
R17
R18
R19
R20
R27
R28
C1
C2
C3
C4
C5
C6
RATING
0Ω
0Ω
0Ω
68kΩ
68kΩ
75kΩ
75kΩ
0Ω
10Ω
10Ω
0Ω
10Ω
10Ω
100kΩ
100kΩ
56kΩ
9.1kΩ
30kΩ
8.2kΩ
0Ω
0Ω
10uF(25V)
10uF(6.3V)
10uF(6.3V)
0.1uF(6.3V)
2200pF(50V)
2200pF(50V)
13
PART No.
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
CM32X7R106M25A
GRM21BB10J106KD
GRM21BB10J106KD
GRM21BB10J104KD
GRM188B11H102KD
GRM188B11H102KD
www.rohm.com
© 2010 ROHM Co., Ltd. All rights reserved.
COMPANY
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
KYOCERA
MURATA
MURATA
MURATA
MURATA
MURATA
DESIGNATION
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C26
D1
D2
L1
L2
Q1
Q2
Q3
Q4
U1
26/33
RATING
0.47uF(10V)
0.47uF(10V)
10uF(25V)
10uF(25V)
330uF
330uF
10pF(50V)
Diode
Diode
2.5uH
2.5uH
FET
FET
FET
FET
-
PART No.
GRM188B11A474KD
GRM188B11A474KD
CM32XR7106M25A
CM32XR7106M25A
6TPB330ML
6TPE330MI
RSX501L-20
RSX501L-20
CDEP105NP-2R5MC-32
CDEP105NP-2R5MC-32
uPA2709
uPA2709
uPA2709
uPA2709
BD9528MUV
COMPANY
MURATA
MURATA
KYOCERA
KYOCERA
SANYO
SANYO
ROHM
ROHM
Sumida
Sumida
NEC
NEC
NEC
NEC
ROHM
2010.03 - Rev.A
Technical Note
BD9528MUV
●Handling method of unused pin during using only DC/DC 1ch
If using only 1ch DC/DC and 2ch pin is set to be off at all times, please manage the unused pin as diagram below.
PIN No,
1
2
3
4
5
6
7
8
10
11
31
PIN name
SW2
HG2
BOOT2
EN2
PGOOD2
SS2
Vo2
ILIM1
FB2
FS2
LG2
VIN
12V
VIN
BD9528MUV
CTL
VIN
VIN
C1
BOOT1
R2
9
22
HG1
R3
21
EN1
4
EN2
SW1
R9
C9
CTL
EN1
REG1
EN1
VIN
R1
30
CTL
Management
GND
Open
Open
GND
GND
GND
GND
GND
GND
GND
Open
23
R10
C10
C7
Q2
VO1
SW1
L1
24
C13
D1
REG1
5V
29
LG1
PGND1
28
R17
R11
C14
C15
C16 C17
C23
Q1
REG1
C2
REG2
3.3V
26
REG2
FB1
25
14
C24
C3
R18
12
REF
19
SS1
6
SS2
Vo1
C4
BOOT2
HG2
C5
17
ILIM1
8
ILIM2
SW2
27
3
2
1
R5
LG2
15
FS1
10
FS2
PGND2
32
FB2
10
Vo2
7
R7
REG1
PGOOD1
R15
MCTL1
PGOOD1
18
20
MCTL1
R28
PGOOD2
5
MCTL2
16
MCTL2 AGND
R27
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© 2010 ROHM Co., Ltd. All rights reserved.
13
27/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Example of PCB layout
L
Vo1
Co
⑥
⑤
L-FET
(CH1)
③
‘Silent’GND
R
FS1
CTL
R
Vo2
EN2
R
R
R
②
C
C
SS2
FS2
PGOOD2
FB2
LG2
BOOT2
REF
VIN
SW2
Cin
AGND
REG1
HG2
C
REG2
PGND2
H-FET
(CH2)
FB1
ILIM2
①
R
R
MCTL2
Vo1
VIN
②
ILMI1
EN1
LG1
PGOOD1
SW1
HG1
PGND1
BOOT1
Cin
④
MCTL1
H-FET
(CH1)
C
SS1
C
High current GND
High current GND
⑤
③
L-FET
(CH2)
‘Silent’GND
⑥
Co
L
Vo2
①Because high pulse current rush into power loop, consisted of input capacitor Cin, Output inductor L, and Output capacitor
Co, this part layout should be built, including GND pattern, at parts side (upper side). Also ,please avoid to draw via formation in
power loop line. (The reason is that it will be a factor of noise because via oneself holds some nH parasitic inductance)
②FB pin has comparatively high impedance, so floating capacity should be minimum as possible. And feedback wiring from
output should be taken properly, and put on shield, not going through around L (because of magnetic). Please be careful in
drawing)
③Trace from SW node pin to inductor should be cut short . And both inductor element pattern should be kept away. (Closer
wiring has SW node noise influence Vo by parasitic capacity between wiring ). This layout example shows that SW node is
outside, but if the application board will be like that , SW node should be shielding, and consider the influence to other circuit.
④Input capacitor Cin should be placed cloase to IC with low inductance and low impedance . If that is difficult, please place a
capacitor for high frequency removal with PKG size small like 0.1uF (ESL small).
⑤2 layer and 3 layer are plain GND, so connect from parts side GND to plain GND by low impedance with many via as possible.
Inner GND is only for shielding, so that not to form loop for high current .
⑥Please take GND pattern space widely, and design layout to be able to increase radiation efficiency.
⑦FS pin nad ILIM pin has high impedance. External resistor should be connected to “Silent GND”.
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28/33
2010.03 - Rev.A
Technical Note
BD9528MUV
Input current A
Input current B
Vin
SW pin voltage
DC/DC
Inductor current
Vout
H3Reg
controller
Feed back line
GND
Power GND
Power GND
Analog GND
Output current GND
Output current GND
This part is shortened.
Current leveled
By capacitor
current
current
Vin
Charger
current
Pulsed current flows by
ON/OFF of the switch
Cin
Input current A
t
Input current B
Noise output !!
This part is shortened.
L
The noise has decreased
by LC filter
Vout
current
Voltage
SW
t
Vin
Inductor ripple current
Cout
Output current
0V
t
t
SW pin voltage
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© 2010 ROHM Co., Ltd. All rights reserved.
Inductor current
29/33
2010.03 - Rev.A
Technical Note
BD9528MUV
The influence of inductor is noted
The impedance of the output is low
= It may be long
SW
L
Vout
Cout
FB
The impedance of this line is high
The impedance of FB pin is higher
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© 2010 ROHM Co., Ltd. All rights reserved.
30/33
This distance is shorted
as much as possible
2010.03 - Rev.A
Technical Note
BD9528MUV
●Notes for use
1. This integrated circuit is a monolithic IC, which (as shown in the figure below), has P+ isolation in the P substrate and
between the various pins. A P-N junction is formed from this P layer and N layer of each pin, with the type of junction
depending on the relation between each potential, as follows:
 When GND＞ element A＞ element B, the P-N junction is a diode.
 When element B＞GND element A, 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, as well as operating malfunctions and physical damage. Therefore, be careful to avoid methods by which
parasitic diodes operate, such as applying a voltage lower than the GND (P substrate) voltage to an input pin.
Resistor
Transistor (NPN)
Pin A
Pin B
C
B
Pin B
E
Pin A
N
N
P
N
+
P
P
+
N
Parasitic
element
P
P substrate
Parasitic element
B
N
P+
P
C
+
N
E
Parasitic
P substrate
GND
Parasitic element
GND
GND
GND
Other adjacent elements
2. In some modes of operation, power supply voltage and pin voltage are reversed, giving rise to possible internal circuit
damage. For example, when the external capacitor is charged, the electric charge can cause a VCC short circuit to the
GND. In order to avoid these problems, inserting a VCC series countercurrent prevention diode or bypass diode between
the various pins and the VCC is recommended.
Bypass diode
Counter current prevention diode
VCC
Pin
3. Absolute maximum rating
Although the quality of this IC is rigorously controlled, the IC may be destroyed when applied voltage or operating temperature
exceeds its absolute maximum rating. Because short mode or open mode cannot be specified when the IC is destroyed, it is important
to take physical safety measures such as fusing if a special mode in excess of absolute rating limits is to be implemented.
4.GND potential
Make sure the potential for the GND pin is always kept lower than the potentials of all other pins, regardless of the operating
mode.
5. Thermal design
In order to build sufficient margin into the thermal design, give proper consideration to the allowable loss (Power Dissipation)
in actual operation.
6. Short-circuits between pins and incorrect mounting position
When mounting the IC onto the circuit board, be extremely careful about the orientation and position of the IC. The IC may
be destroyed if it is incorrectly positioned for mounting. Do not short-circuit between any output pin and supply pin or ground,
or between the output pins themselves. Accidental attachment of small objects on these pins will cause shorts and may
damage the IC.
7. Operation in strong electromagnetic fields
Use in strong electromagnetic fields may cause malfunctions. Use extreme caution with electromagnetic fields.
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© 2010 ROHM Co., Ltd. All rights reserved.
31/33
2010.03 - Rev.A
Technical Note
BD9528MUV
8. Thermal shutdown circuit
This IC is provided with a built-in thermal shutdown (TSD) circuit, which is activated when the operating temperature reaches
175℃ (standard value), and has a hysteresis range of -15℃ (standard value). When the IC chip temperature rises to the
threshold, all the inputs automatically turn OFF. Note that the TSD circuit is provided for the exclusive purpose shutting down
the IC in the presence of extreme heat, and is not designed to protect the IC per se or guarantee performance when or after
extreme heat conditions occur. Therefore, do not operate the IC with the expectation of continued use or subsequent
operation once the TSD is activated.
9. Capacitor between output and GND
When a larger capacitor is connected between the output and GND, Vcc or VIN shorted with the GND or 0V line – for any
reason – may cause the charged capacitor current to flow to the output, possibly destroying the IC. Do not connect a
capacitor larger than 1000uF between the output and GND.
10. Precautions for board inspection
Connecting low-impedance capacitors to run inspections with the board may produce stress on the IC. Therefore, be certain
to use proper discharge procedure before each process of the operation. To prevent electrostatic accumulation and
discharge in the assembly process, thoroughly ground yourself and any equipment that could sustain ESD damage, and
continue observing ESD-prevention procedures in all handling, transfer and storage operations. Before attempting to
connect components to the test setup, make certain that the power supply is OFF. Likewise, be sure the power supply is
OFF before removing any component connected to the test setup.
11. GND wiring pattern
When both a small-signal GND and high current GND are present, single-point grounding (at the set standard point) is
recommended, in order to separate the small-signal and high current patterns, and to be sure the voltage change stemming
from the wiring resistance and high current does not cause any voltage change in the small-signal GND. In the same way,
care must be taken to avoid wiring pattern fluctuations in any connected external component GND.
●Thermal Derating Curve
◎ VQFN032V5050
[mW]
1000
74.2mm×74.2mm×1.6mm
θj-a=142.0℃/W
880mW
Glass-epoxy PCB
Power Dissipation [Pd]
800
600
IC Only θj-a=328.9℃/W
400
380mW
200
0
25
50
75
100
125
150
[℃]
Ambient Temperature [Ta]
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© 2010 ROHM Co., Ltd. All rights reserved.
32/33
2010.03 - Rev.A
Technical Note
BD9528MUV
●Ordering part number
B
D
9
Part No.
5
2
8
M
Part No.
U
V
Package
MUV: VQFN032V5050
-
E
2
Packaging and forming specification
E2: Embossed tape and reel
VQFN032V5050
<Tape and Reel information>
5.0 ± 0.1
5.0±0.1
1.0MAX
3.4±0.1
0.4 ± 0.1
1
8
9
32
16
25
24
0.75
0.5
2500pcs
E2
The direction is the 1pin of product is at the upper left when you hold
)
(0.22)
( reel on the left hand and you pull out the tape on the right hand
3.4 ± 0.1
+0.03
0.02 -0.02
S
C0.2
Embossed carrier tape
Quantity
Direction
of feed
1PIN MARK
0.08 S
Tape
17
+0.05
0.25 -0.04
1pin
(Unit : mm)
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© 2010 ROHM Co., Ltd. All rights reserved.
Reel
33/33
Direction of feed
∗ Order quantity needs to be multiple of the minimum quantity.
2010.03 - Rev.A
Notice
Notes
No copying or reproduction of this document, in part or in whole, is permitted without the
consent of ROHM Co.,Ltd.
The content specified herein is subject to change for improvement without notice.
The content specified herein is for the purpose of introducing ROHM's products (hereinafter
"Products"). If you wish to use any such Product, please be sure to refer to the specifications,
which can be obtained from ROHM upon request.
Examples of application circuits, circuit constants and any other information contained herein
illustrate the standard usage and operations of the Products. The peripheral conditions must
be taken into account when designing circuits for mass production.
Great care was taken in ensuring the accuracy of the information specified in this document.
However, should you incur any damage arising from any inaccuracy or misprint of such
information, ROHM shall bear no responsibility for such damage.
The technical information specified herein is intended only to show the typical functions of and
examples of application circuits for the Products. ROHM does not grant you, explicitly or
implicitly, any license to use or exercise intellectual property or other rights held by ROHM and
other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the
use of such technical information.
The Products specified in this document are intended to be used with general-use electronic
equipment or devices (such as audio visual equipment, office-automation equipment, communication devices, electronic appliances and amusement devices).
The Products specified in this document are not designed to be radiation tolerant.
While ROHM always makes efforts to enhance the quality and reliability of its Products, a
Product may fail or malfunction for a variety of reasons.
Please be sure to implement in your equipment using the Products safety measures to guard
against the possibility of physical injury, fire or any other damage caused in the event of the
failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM
shall bear no responsibility whatsoever for your use of any Product outside of the prescribed
scope or not in accordance with the instruction manual.
The Products are not designed or manufactured to be used with any equipment, device or
system which requires an extremely high level of reliability the failure or malfunction of which
may result in a direct threat to human life or create a risk of human injury (such as a medical
instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuelcontroller or other safety device). ROHM shall bear no responsibility in any way for use of any
of the Products for the above special purposes. If a Product is intended to be used for any
such special purpose, please contact a ROHM sales representative before purchasing.
If you intend to export or ship overseas any Product or technology specified herein that may
be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to
obtain a license or permit under the Law.
Thank you for your accessing to ROHM product informations.
More detail product informations and catalogs are available, please contact us.
ROHM Customer Support System
http://www.rohm.com/contact/
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© 2010 ROHM Co., Ltd. All rights reserved.
R1010A