○Product structure：Silicon monolithic integrated circuit ○This product is not designed protection against radioactive rays
1/29 TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・14・001
Single-chip Type with Built-in FET Switching Regulator Series
Step-down Switching regulators
with Built-in Power MOSFET
BU9000xGWZ series
●General Description
The BU9000xGWZ are a high efficiency 6MHz
synchronous step-down switching regulator with ultra
low current PFM mode.
It provides up to 1.0A load current and an input voltage
range from 3.0V to 5.5V, optimized for battery powered
portable applications.
BU9000xGWZ has a mode control pin that allows the
user to select Forced PWM (Pulse Width Modulation)
mode or PFM (Pulse Frequency Modulation) and PWM
auto change mode utilized power save operation at light
load current.
●Features
Fast transient response
Automatic PFM/PWM operation
Forced PWM operation
Internal Soft Start
Under voltage lockout
Over current protection
Thermal shutdown
●Lineup
●Pin Configuration(s)
●Applications
Smart phones, Cell phones, Portable applications,
Micro DC/DC modules, and USB accessories
●Package(s) W(Typ.) x D(Typ.) x H(Max.)
UCSP35L1 1.30mm x 0.90mm x 0.40mm
●Typical Application Circuit(s)
●Pin Description(s)
Part No. Output
voltage Input voltage Switching frequency Operating mode
MODE=L MODE=H
BU90002GWZ 3.30V 4.0V to 5.5V 5.4MHz to 6.6MHz Automatic
PFM/PWM
Forced PWM
BU90003GWZ 1.20V 2.3V to 5.5V 3.6MHz to 4.4MHz
BU90004GWZ 1.80V 2.3V to 5.5V 4.8MHz to 6.0MHz
BU90005GWZ 2.50V 2.3V to 5.5V 5.4MHz to 6.6MHz Forced PFM
BU90006GWZ 3.00V 2.3V to 5.5V 5.4MHz to 6.6MHz
Automatic
PFM/PWM
BU90007GWZ 1.25V 2.3V to 5.5V 3.6MHz to 4.4MHz
BU90008GWZ 1.00V 2.3V to 5.5V 3.2MHz to 4.0MHz
BU90009GWZ 1.30V 2.3V to 5.5V 3.8MHz to 4.8MHz
Pin No. Symbol Function
A1 VIN Power supply input pin
A2 EN Enable pin
A3 GND GND pin
B1 MODE Forced PWM mode pin
B2 LX Inductor connection pin
B3 FB Feedback voltage input pin
Figure 1. Typical Application Circuit(s)
(BOTTOM VIEW)
Figure 2. Pin Configuration(s)
Datashee
t
2/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Block Diagram(s)
●Description of Block(s)
The BU9000xGWZ are a syn c hronous step-down DC/DC converter that achieves fast transient respons e from light load to
heavy load by hysteretic PWM control system and current constant PFM control system.
○PWM control
BU9000xGWZ operates by hysteretic PWM control. This scheme ensures fast switching, high efficiency, and fast transient
response.
When the output voltage is belo w the VREF voltage, the error comparator output is low to high and turning on P-chan nel
MOSFET until above the VREF voltage and minimum on time.
○PFM control
At light load the regulator and MODE=low, the regulator operates with reduced switching frequ ency and improves the
efficiency.During PFM operation, the outp ut voltage slightly higher than typical output voltage.
Figure 4. Operation of PFM mode and PWM mode
Figure 3. Block Diagram(s)
GND
LX
VIN
EN SHUTDOWN
TSD
ERROR COMP
FB
Frequency
control
UVLO
VREF
Switching
Control Logic
and
Gate Driver
MODE
PWM/PFM
control
B1
1.5～0.47uH
4.7～10uF
VOUT
2.3～5.5V
VOUT
H ：　ON
L ：　OFF
L ：　PWM/PFM MODE
H ：　PWM MODE
A1
B2
A3
A2
B3
EN
3/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Description of operations
1) Shutdown
If the EN input pin set to low (<0.4V), all circuit are shut down and the regulator is standby mode.
Do not leave the EN pin floating.
2) Soft start function
The regulator has a soft start circuit that reduces in-rush current at start-up. Typical start up times with a 4.7uF output
capacitor is 120usec.
3) Current limit
The BU9000xGWZ has a current limit circuit that protects itself and external components during overloa d condition.
4) UVLO
The BU9000xGWZ has a Under Voltage Lock Out circuit that turn off device when VIN>2.05V(typ.)
5) FORCED PWM MODE
Setting MODE pin high (>1.4V) places the regulator in forced PWM.This control provides noise r eduction and output
stability.Do not leave the MODE pin floating.
6) FORCED PFM MODE ( BU90005GWZ)
Setting MODE pin low (<0.4V) places the regulator in forced PFM. It is effective in light load mode.
7) TSD
The BU9000xGWZ has a thermal shutdown feature to protect the device if the junction temperature exceeds 150℃.In
thermal shutdown, the DRIVER is disabled.
This circuit is only to cut off the IC from thermal runaway, and has not been design to pro tect or guarantee the IC. Therefore,
the user should not plan to activate this circuit with continued operation in mind.
●Absolute Maximum Ratings (Ta=25℃)
(*1) When mounted on the specified PCB (55mm x 63mm), Deducted by 3.9m W/c when used over Ta=25c
●Recommended Operating Rating(s)
Parameter Symbol Rating Unit
Maximum input po wer supply voltage VIN 7 V
Maximum voltage at EN, FB, LX, MODE VEN, VFB,
VLX, VMODE 7 V
Power dissipation Pd 0.39(*1) W
Operating temperature range Topr -40 to +85 ℃
Storage temper ature range Tstg -55 to +125 ℃
Junction temperature Tjmax +125 ℃
Parameter Symbol Rating Unit Serise
Min. Typ. Max.
Input voltage VIN 4.0 - 5.5 V BU90002GWZ
2.3 - 5.5 BU90003～BU90009GWZ
4/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical Characteristic(s ) (unless otherwise specified VIN=3.6V, Ta=25℃)
Item Symbol
Rating Unit Condition
Min. Typ. Max.
【Switching regulator】
Output voltage accuracy VOUTA -2 - +2
% MODE:H(PWM Operation)
-2 - +3 MODE:L (PFM Operation)
Maximum load current
IoutMAX1 - - 1.0 A
3.0V≦VIN＜5.5V
IoutMAX2 - - 0.8 A
2.7V≦VIN＜3.0V
IoutMAX3 - - 0.6 A
2.3V≦VIN＜2.7V
IoutMAX4 - - 0.1 A
MODE:L(PFM Operation)
(BU90005GWZ,)
【Soft start】
Soft start time Tss 65 120 240 usec
( BU90002GWZ, BU90003GWZ,
BU90004G WZ, BU900 05GWZ,
BU90006G WZ, BU900 07GWZ,
BU90009GWZ )
55 110 220 usec
( BU90008GWZ )
【Frequency control】
Switching frequency fosc
5.4 6.0 6.6 MHz
No load, MODE:H
( BU90002GWZ,BU90005GWZ,
BU90006GWZ)
4.8 5.4 6.0 MHz
No load, MODE:H
( BU90004GWZ )
3.6 4.0 4.4 MHz
No load, MODE:H
( BU90003GWZ, BU90007GWZ )
3.2 3.6 4.0 MHz
No load, MODE:H
( BU90008GWZ )
3.8 4.3 4.8 MHz
No load, MODE:H
( BU90009GWZ )
【Driver】
PchFET on resistance RonP1 - 250 400 mOhm
VIN=5.0V
RonP2 300 450 mOhm
VIN=3.6V
NchFET on resistance RonN1 - 220 350 mOhm
VIN=5.0V
RonN2 250 380 mOhm
VIN=3.6V
【Control】
EN pin control
voltage Operation VENH 1.4 - VIN V
Non Operation VENL 0 - 0.4 V
MODE pin
control voltage Operation VMODEH 1.4 - VIN V
Forced PWM
Non Operation VMODEL 0 - 0.4 V Automatic PFM/PWM
(BU90005GWZ : Forced PFM)
【UVLO】
Protect threshold voltage Uvth 1.95 2.05 2.15 V
Hysteresis Uvhy 50 100 150 mV
【Current limit】
Current limit threshold ILIMIT 1.5 1.7 1.9 A
PMOS current detect,
Open loop
【Output discharge】
Output discharge resistance DRES 15 30 60 Ohm EN=0V, FB=0.5V
【Circuit current】
Operating quiescent current
IINS1 - 45 65 uA
No load, EN:H, MODE:L,
VOUT=3.6V forced
Not switching
( BU90003GWZ, BU90004GWZ,
BU90005G WZ, BU900 07GWZ,
BU90008G WZ, BU900 09GWZ )
IINS2 - 55 80 uA
No load, EN:H, MODE:L,
VOUT=3.6V forced
Not switching
( BU90002GWZ,BU90006GWZ )
IQ1 - 5.2 - mA
No load, EN:H, MODE:H,
PWM operation
L:LQM21MPN1R0NG0
( BU90003GWZ )
IQ2 - 5.6 - mA
No load, EN:H, MODE:H,
PWM operation
L:LQM21MPN1R0NG0
( BU90004GWZ )
Shutdown current SHD - 0 1 uA EN=0V
5/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical Characteristic curves (Reference da ta)
BU90002GWZ (3.3V OUTPUT)
Parts
L:LQM21MPN1R0NG0 (2.0mm×1.6mm×1.0mm Murata)
COUT:GRM155R60J475M(1.0mm×0.5mm×0.5mm Murata)
Figure 5. Start up
Figure 7. Load transient response 5mA to 50mA
tr=tf=100ns, MODE : Low
Figure 8. Load transient response 50mA to 350mA
tr=tf=100ns, MODE : Low
Figure 6. Shut down
VOUT
2V/div
EN
2V/div
IL
500mA/div
20us
EN
2V/div
VOUT
2V/di
v
100us
Vout
50mV/div
ac coupled
IOUT
50mA/di
v
10us
Vout
50mV/div
ac coupled
IOUT
200mA/di
v
4us
6/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 9. Load transient response 150mA to 500mA
tr=tf=100ns, MODE : High Figure 10. PFM mode Operation
Iout=40mA
Figure 12. Mode Change Response
MODE : High to Low
Figure 11. PWM mode Opera t ion
Iout=100mA
Vout
50mV/div
ac coupled
IOUT
200mA/div
Vout
20mV/div
ac coupled
LX
5V/di
v
IL
500mA/di
v
IL
500mA/div
Vout
20mV/div
ac coupled
LX
5V/div
MODE
2V/di
v
Vout
20mV/div
ac coupled
IL
500mA/div
4us
400ns
80ns
4us
7/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
60
65
70
75
80
85
90
95
100
1 10 100 1000
Efficiency[%]
Load curren t [mA]
3.31
3.32
3.33
3.34
3.35
3.36
3.37
3.38
0 200 400 600 800 1000
Output Voltage[v]
L oad curren t [ mA]
0
5
10
15
20
25
30
0 200 400 600 800 1000
Vout Ripple Voltage[mv]
Lo ad cu rrent[ mA]
Figure 13. Mode Change Response
MODE : Low to High Figure 14. Efficiency vs Load current
VIN=5V PWM/PFM Auto mode
Figure 15. Load regulation
VIN=5V PWM/PFM Auto mode Figure 16. Vout Ripple Voltage
VIN=5V PWM/PFM Auto mode
MODE
2V/div
Vout
20mV/div
ac coupled
IL
500mA/div
4us
8/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical characteristic curves (Reference data )
BU90003GWZ (1.2V OUTPUT)
Figure 17. Start up Figure 18. Shut down
Figure 19. Load transient response 5mA to 200mA
tr=tf=100ns, MODE : Low Figure 20. Load transient response 50mA to 350mA
tr=tf=100ns, MODE : Low
EN
2V/div
VOUT
500mV/div
IL
200mA/div
VOUT
500m/div
EN
2V/div
Vout
50mV/div
1.2V offset
IOUT
200mA/div
Vout
50mV/div
1.2V offset
IOUT
200mA/div
40us
100us
4us
10us
9/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 23. Fig.23 PWM mode Operation Iout = 100mA Figure 24. Mode Change Response
MODE : High to Low
Figure 21. Load transient response 400mA to 1000mA
tr=tf=100ns, MODE : Low Figure 22. PFM mode Operation Iout=50mA
IOUT
500mA/div
Vout
50mV/div
ac coupled
LX
2V/div
Vout
20mV/div
ac coupled
IL
500mA/div
LX
2V/div
IL
500mA/div
Vout
20mV/div
ac coupled
MODE
2V/div
Vout
50mV/div
ac coupled
IL
200mA/div
4us
400ns
80ns
2us
10/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
1.188
1.200
1.212
1.224
1.236
0 200 400 600 800 1000
Output Voltage[V]
Load current [mA]
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency[%]
Load current[ mA]
Figure 25. Mode Change Response
MODE : Low to High Figure 26. Efficiency vs Load current
PWM/PFM Auto mode
Figure 27. Load regulation
PWM/PFM Auto mode
IL
200mA/div
Vout
50mV/div
ac coupled
MODE
2V/div
2us
VIN=2.7V
VIN=3.6V
VIN=4.2V
VIN=4.2
VIN=3.6
VIN=2.7
11/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical characteristic curves (Reference data )
BU90004GWZ (1.80V OUTPUT)
Figure 28. Start up Figure 29. Shut down
Figure 30. Load transient response 5mA to 200mA
tr=tf=100ns, Mode : Low Figure 31. Load transient response 50mA to 350mA
tr=tf=100ns, Mode :Low
Vout
50mV/div
ac coupled
IOUT
200mA/div
EN
5V/div
VOUT
1V/div
Vout
50mV/div
ac coupled
IOUT
200mA/div
EN
5V/div
VOUT
1V/div
IL
200mA/div
40us 100us
4us
4us
12/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 32. Load transient response 200mA to 600mA
tr=tf=100ns, MODE : Low Figure 33. PFM mode Operation IIout=50mA
Figure 34. PWM mode Operation Iout=100mA Figure 35. Mode Change R esponse
MODE : High to Low
MODE
5V/div
Vout
50mV/div
ac coupled
LX
200mA/div
Vout
20mV/div
ac coupled
LX
2V/div
Vout
50mV/div
ac coupled
IOUT
200mA/div
Vout
20mV/div
ac coupled
LX
2V/div
4us
80ns
400ns
4us
13/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency[%]
Load current[mA]
1.764
1.782
1.800
1.818
1.836
1.854
0 200 400 600 800 1000
Output Voltage[V]
Load current[mA]
Figure 36. Mode Change Response
MODE : Low to High
Figure 38. Load regulation
PWM/PFM Auto mode
Figure 37. Efficiency vs Load current
PWM/PFM Auto mode
MODE
5V/div
Vout
50mV/div
ac coupled
LX
200mA/div
2us
VIN=2.7V
VIN=3.6V
VIN=4.2V
VIN=2.7V
VIN=3.6V
VIN=4.2V
14/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical characteristic curves (Reference data )
BU90005GWZ (2.50V OUTPUT)
Figure 39. Start up Figure 40. Shut down
Figure 41. Load transient response 5mA to 100mA
tr=tf=100ns, MODE : Low Figure 42. Load transient response 50mA to 350mA
tr=tf=100ns, MODE : High
Vout
100mV/div
ac coupled
IOUT
200mA/div
EN
2V/div
VOUT
1V/div
Vout
50mV/div
ac coupled
IOUT
100mA/div
EN
1V/div
VOUT
1V/div
IL
200mA/div
40us 100us
4us 4us
15/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 43. Load transient response 200mA to 600mA
tr=tf=100ns, MODE : High Figure 44. PFM mode Operation Iout=50mA
Figure 45. PWM mode Operation Iout=100mA Figure 46. Mode Change Response
MODE : High to Low
MODE
2V/div
Vout
50mV/div
ac coupled
IL
200mA/div
Vout
50mV/div
ac coupled
LX
2V/div
Vout
100mV/div
ac coupled
IOUT
200mA/div
Vout
20mV/div
ac coupled
LX
2V/div
10us
1us
80ns
4us
IL
500mA/div
IL
200mA/div
16/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency[%]
Load current[mA]
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100
Efficiency[%]
Load current[mA]
Figure 47. Mode Change Response
MODE : Low to High Figure 48. Efficiency vs Load current
PFM mode
Vout
50mV/div
ac coupled
Figure 49. Efficiency vs Load current
PWM mode
4us
MODE
2V/div
IL
200mA/div
VIN=2.7V
VIN=3.6V
VIN=4.2V
VIN=2.7V
VIN=3.6V
VIN=4.2V
17/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical characteristic curves (Reference data )
BU90008GWZ (1.000V OUTPUT)
100us
Figure 50. Start up
Figure 52. Load transient response 5mA to 100mA
tr=tf=100ns, MODE : Low Figure 53. Load transient response 50mA to 350mA
tr=tf=100ns, MODE : High
Figure 51. Shut down
VOUT
500ｍV/div
EN
2V/div
IL
200mA/div
EN
2V/div
VOUT
500mV/di
v
Vout
50mV/div
ac coupled
IOUT
200mA/di
v
20us
Vout
50mV/div
ac coupled
IOUT
200mA/di
v
20us
40us
18/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 54. Load transient response 200mA to 600mA
tr=tf=100ns, MODE : High Figure 55. PFM mode Operation Iout=50mA
Figure 57. Mode Change Response
MODE : High to Low
Figure 56. PWM mode Operation Iout=100mA
Vout
50mV/div
ac coupled
IOUT
500mA/di
v
Vout
20mV/div
ac coupled
LX
2V/di
v
IL
200mA/div
IL
200mA/div
Vout
20mV/div
ac coupled
LX
2V/di
v
MODE
2V/di
v
Vout
50mV/div
ac coupled
IL
200mA/div
20us
1us
200ns
4us
19/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 58. Mode Change Response
MODE : Low to High Figure 59. Efficiency vs Load current
PFM mode
Figure 60. Efficiency vs Load current
PWM mode
MODE
2V/div
Vout
50mV/div
ac coupled
IL
200mA/div
4us
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency [%]
Load current [mA ]
VIN=2.7V
VIN=3.6V
VIN=4.2V
0.980
0.990
1.000
1.010
1.020
0 200 400 600 800 1000
Output Volt age [V]
Load current[mA ]
VIN=2.7V
VIN=3.6V
VIN=4.2V
20/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Electrical characteristic curves (Reference data )
BU90009GWZ (1.300V OUTPUT)
100us
Figure 61. Start up
Figure 63. Load transient response 5mA to 50mA
tr=tf=100ns, MODE : Low Figure 64. Load transient response 50mA to 350mA
tr=tf=100ns, MODE : Lo
w
Figure 62. Shut down
VOUT
500ｍV/div
EN
2V/div
IL
200mA/div
EN
2V/div
VOUT
500mV/di
v
Vout
50mV/div
ac coupled
IOUT
100mA/di
v
Vout
50mV/div
ac coupled
IOUT
200mA/di
v
40us
20us 20us
21/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
Figure 65. Load transient response 150mA to 500mA
tr=tf=100ns, MODE : High Figure 66. PFM mode Operation
Iout=50mA
Figure 68. Mode Change Response
MODE : High to Low
Figure 67. PWM mode Operation Iout=100mA
Vout
50mV/div
ac coupled
IOUT
200mA/di
v
Vout
20mV/div
ac coupled
IL
200mA/div
IL
200mA/div
Vout
20mV/div
ac coupled MODE
2V/div
Vout
50mV/div
ac coupled
IL
200mA/div
20us
1us
200ns
4us
LX
2V/di
v
LX
2V/di
v
22/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Efficiency [%]
Load current [mA ]
VIN=2.7V
VIN=3.6V
VIN=4.2V
1.274
1.287
1.300
1.313
1.326
0 200 400 600 800 1000
Output Voltage[V]
Load current[mA ]
VIN=2.7V
VIN=3.6V
VIN=4.2V
Figure 69. Mode Change Response
MODE : Low to High Figure 70. Efficiency vs Load current
PWM/PFM Auto mode
Figure 71. Load regulation
PWM/PFM Auto mode
MODE
2V/div
Vout
50mV/div
ac coupled
IL
200mA/div
4us
23/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●PC Board layout
The suggested PCB layout for the BU9000xGWZ are shown in Figure. The following guidelines sh ould be used to ensure a
proper layout.
1) The input capacitor CIN should be connect as closely possible to VIN pin and GND pin .
2) From the output voltage to the FB pin line should be as s eparate as possible.
3) COUT and L should be connected as closely as possible. The connection of L to the LX pin should be as short as
possible.
Figure 72. PCB layout
●External parts selection
Inductor selection
The inductance significantly depends on output ripple current. As shown by following equation, the ripple current decreases
as the inductor and/or switching frequency increase.
f: switching frequency L: inductance ⊿IL: inductor current ripple
As a minimum requirement, the DC current rating of the i nd uctor should be equ al to the maximum load current plus half of
the inductor current ripple as shown by the following equation.
(VIN-VOUT)×VOUT
⊿IL= L×VIN×f
⊿IL
ILPEAK= 2
IOUTMAX +
24/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
1 ) Recommended inductor selection
・Iout≦1A
LQM2MPN1R0NG0 (2.0mm×1.6mm×1.0mm Murata)
MIPSZ2016D1R0FH (2.0mm×1.6mm× 1.0mm F DK)
DFE252012C1R0 (2.5mm×2.0mm×1.2mm TOKO)
・Iout≦0.6A
LQM21PN1R0NGC (2.0mm×1.2mm×1.0mm Murata)
MIPSZ2012D1R0 (2.0mm×1.2mm×1.0mm FDK)
MIPSTZ1608D1R0 (1.6mm×0.8mm×0.8mm FDK)
MLP2012H1R0M (2.0mm×1.2mm×1.0mm TDK)
CKP2012N1R0N (2.0mm×1.2mm×1.0mm Taiyo Yuden)
2 ) Recommended input capacitor(CIN) selection
GRM155R60J225M(1.0mm×0.5mm×0.5mm Murata)
GRM155R60J475M(1.0mm×0.5mm×0.5mm Murata)
GRM155R60G106M(1.0mm×0.5mm×0.5mm Murata)
3 ) Recommended output capacitor(COUT) selection
GRM155R60J475M(1.0mm×0.5mm×0.5mm Murata)
GRM155R60G106M(1.0mm×0.5mm×0.5mm Murata)
○Cautions on the output capacitor selection
The BU9000xGWZ is designed to fixed soft-start time and operate with a maximum output capacitance of 10uF.
If the capacitance connected to the output is larger than 10u F, an overshoot of the output voltage will be caused.
It is possible to cause damage on the conne cted device.
25/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●I/O equivalence circuit(s)
A2 EN B1 MODE
B2 LX B3 FB
VIN VIN
VINVIN
26/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Caution of use
1) Absolute maximum ratings
An excess in the absolute maximum rating, such as supp ly voltage, temperature range of operating conditions, etc., can
break down the devices, thus making impossible to identify breaking mode, such as a short circuit or an open circuit. If
any over rated values will expect to exceed the absolute maximum ratings, consider adding circuit protection devices,
such as fuses.
2) GND voltage
The potential of GND pin must be minimum pot ential in all condition. As an exc eption, the circuit design allows voltages
up to -0.3 V to be applied to the IC pin.
3) Thermal design
Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating
conditions.
4) Inter-pin shorts and mounting errors
Use caution when positioning the IC for mounting on printed circuit boards. The IC may be damaged if there is any
connection error or if pins are shorted togeth er.
5) Actions in strong electromagnetic field
Use caution when using the IC in the presence of a strong electromagnetic field as doing so may cause the IC to
malfunction.
6) Mutual impedance
Power supply and grou nd wiring should refl ect consideration of the need to lo wer mutual impedance and minimize rip ple
as much as possible (by maki ng wiring as short and thick as possib le or rejecting ripple by incorporatin g inductance and
capacitance).
7) Thermal shutdown Circuit (TSD Circuit)
This model IC has a built-in TSD circuit. This circuit is only to cut off the IC from thermal runaway, and has not been
design to protect or guarantee the IC. Therefore, the user should not pla n to activate this circuit with continued operation
in mind.
8) Regarding input pin of the IC
This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them
isolated.
P-N junctions are formed at the intersection of these P layers with the N layers of other elements, creating a parasitic
diode or transistor. For example, as shown in the figures below, the relation between each potential is as follows:
When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.
When GND > Pin B, the P-N junction operates as a parasitic transistor.
Parasitic diodes can occur inevitable in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Accordingly, methods by which parasitic diodes
operate, such as applying a voltage that is lower than the GND (P substrate) voltage to an input pin, should not be used.
9) Disturbance light
In a device where a portion of silicon is e xposed to light such as in a WL-CSP, IC characteristics may be affected due to
photoelectric effect. For this reason, it is recommended to come up with countermeasures that will prevent the chip from
being exposed to light.
Status of this document
The Japanese version of this document is formal specification. A customer may use this translation version only for a
reference to help reading the formal versi on.
If there are any differences in translation version of this document formal version takes priority
27/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Ordering Information
B U 9 0 0 0 x G W Z E 2
Part Number
Package
GWZ: UCSP35L1
Packaging and forming specifi cation
E2: Embossed tape and reel
(UCSP35L1)
●Marking Diagram(s)(TOP VIEW)
Series Part Number Marking
BU90002GWZ AB4
BU90003GWZ AB6
BU90004GWZ AB7
BU90005GWZ AB8
BU90006GWZ AB9
BU90007GWZ ACM
BU90008GWZ ADW
BU90009GWZ ADV
28/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Physical Dimension, Tape and Reel Information
Package Name UCSP35L1
< Tape and Reel Information >
Tape Embossed carrier tape
Quantity 3,000pcs
Direction of feed E2
The direction is the pin 1 of product is at the upper left when you hold
reel on the left hand and you pull o ut the tape on the right h and
(Unit： mm）
Reel Direction of feed
1pin
1234 1234 1234 1234 1234 1234
29/29
Datasheet
Datasheet
BU9000xGWZ series
TSZ02201-0F2F0AG00010-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 7.Jul.2015 Rev.007
www.rohm.com
TSZ22111・15・001
●Revision History
Date Revision Changes
04.Jul.2012 001 New Release
16.Oct.2013 002 Page18
1 ) Recommended inductor selection
MIPSZ2016D1R0FH, MIPSZ2012D1R0 added.
28.Oct.2013 003
Page4
Electrical Characteristic(s)
Operating quiescent current
IQ1(BU90003GWZ PWM operation), IQ2(B U90004GWZ PWM operation) added.
29.May.2014 004
Page19
I/O equivalence circuit added.
Page20⇒Page22
Physical Dimension, Tape and Reel Information
8.Dec.2014 005
Page20
Caution of use
9) Disturbance light added.
15.May.2015 006
BU90008GWZ added.
Page 2
Figure 3. Block Diagram(s)
Range of the output capacitor capacity added.
Page21
Cautions on the output capacitor selection added.
7.Jul.2015 007
BU90009GWZ added.
Page 4
Output discharge resistance
Correction of errors