AS1331 Datasheet

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Data sheet
AS1331
300mA Buck-Boost Synchronous DC/DC Converters
2 Key Features
Due to the internal structure of the AS1331 which is
working continuously through all operation modes this
device is ideal for dual or triple cell alkaline/NiCad/NiMH
as well as single cell Li-Ion battery applications.
Input Voltage Range: 1.8V to 5.5V
!
Output Voltages:
- Fixed: 2.5V, 3.0V, 3.3V
- Adjustable: 2.5V to 3.3V
!
Output Current: 300mA @ 3.3V
!
Up to 90% efficiency
!
Power Good
!
Output Disconnection in Shutdown
!
Automatic transition between Buck and Boost mode
!
Ultra Low Quiescent Current: 22µA, Shutdown Current <1µA (Active Low)
!
Short-Circuit Protection
!
Low Battery detection
!
Over Temperature Protection
!
10-pin 3x3mm TDFN package
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Because of the implemented Power Save Mode, the
solution footprint and the component count is minimized
and also over a wide range of load currents a high
conversion efficiency is provided.
!
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This special device is a synchronous buck-boost DC/DC
converter which can handle input voltages above, below,
or equal to the output voltage.
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1 General Description
The device includes two N-channel MOSFET switches
and two P-channel switches. Also following features are
implemented: a quiescent current of typically 22µA
(ideal for battery power applications), a shutdown
current less than 1µA, current limiting, thermal shutdown
and output disconnect.
The AS1331 is available in a 10-pin 3x3mm TDFN
package with fixed and adjustable output voltage.
3 Applications
The AS1331 is an ideal solution for handheld
computers, handheld instruments, portable music
players and PDA’s. Two and three cell Alkaline, NiCd or
NiMH or single cell Li battery powered products.
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Figure 1. AS1331 - Typical Application Diagram
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1.8V to 5.5V
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C1
10µF
L1
6.8µH
4 SW1
2 SW2
5
8
VIN
R4
7
LBI
R5
On
Off
LBO
AS1331-AD
Low Battery Detect
R3
1
VOUT
R1
10
6
C2
22µF
VOUT
2.5V to 3.3V
FB
EN
R2
3 PGND
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9 GND
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AS1331
Datasheet - P i n A s s i g n m e n t s
4 Pin Assignments
Figure 2. Pin Assignments (Top View)
VOUT 1
10 FB
PGND 3
AS1331
SW1 4
8 LBO
7 LBI
11
6 EN
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VIN 5
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9 GND
SW2 2
Pin Descriptions
SW2
VIN
EN
LBI
LBO
GND
4
5
6
7
8
9
10
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FB
Pin
Number
1
2
3
Description
Output of the Buck/Boost Converter.
Buck/Boost Switch Pin. Connect the inductor from SW1 to SW2
Power Ground. Both GND pins must be connected.
Buck/Boost Switch Pin. Connect the inductor from SW1 to SW2. An
optional Schottky diode can be connected between this pin and VOUT to
increase efficiency.
Input Supply Pin. A minimum 2.2µF capacitor should be placed between
VIN and GND.
Enable Pin. Logic controlled shutdown input.
1 = Normal operation;
0 = Shutdown; quiescent current <1µA.
Low Battery Comperator Input. 1.25V Threshold. May not be left floating.
If connected to GND LBO is working as Output Power okay.
Low Battery Comperator Output. This open-drain output is low when the
voltage on LBI is less than 1.25V.
Ground. Both GND pins must be connected.
Feedback Pin. Feedback input for the adjustable version. Connect a
resistor divider tap to this pin. The output voltage can be adjusted from 2.5V
to 3.3V by: VOUT = 1.25V[1 + (R1/R2)]
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Pin
Name
VOUT
SW1
PGND
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Table 1. Pin Descriptions
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Note: For the fixed Output Voltage Version contact this pin to VOUT.
Exposed Pad. This pad is not connected internally. It can be used for
ground connection between GND and PGND.
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AS1331
Datasheet - A b s o l u t e M a x i m u m R a t i n g s
5 Absolute Maximum Ratings
Stresses beyond those listed in Table 2 may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in Electrical
Characteristics on page 4 is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
Min
Max
Units
SW1, SW2, VIN, VOUT, EN
-0.3
+7
V
PGND to GND
-0.3
+0.3
V
SW1, SW2
-0.3
+7
V
4
kV
Thermal Resistance θJA
+33
ºC/W
Junction Temperature
+150
ºC
HBM MIL-Std. 883E 3015.7 methods
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ESD
Notes
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Parameter
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Table 2. Absolute Maximum Ratings
Operating Temperature Range
-40
85
ºC
Storage Temperature Range
-65
+125
ºC
+260
ºC
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Package Body Temperature
The reflow peak soldering temperature
(body temperature) specified is in
accordance with IPC/JEDEC J-STD020D “Moisture/Reflow Sensitivity
Classification for Non-Hermetic Solid
State Surface Mount Devices”.
The lead finish for Pb-free leaded
packages is matte tin (100% Sn).
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AS1331
Datasheet - E l e c t r i c a l C h a r a c t e r i s t i c s
6 Electrical Characteristics
VIN = 3.6V, VOUT = 3.3V, TAMB = -40°C to +85ºC. Typical values are at TAMB = +25ºC. Unless otherwise specified.
Table 3. Electrical Characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Units
5.5
V
1.8
V
1.7
V
Input Voltage Range
1.8
Minimum Startup Voltage
Undervoltage Lockout
VUV
ILOAD < 1mA
VIN decreasing
1
Threshold
1.6
1.5
Regulation
2.50
Output Voltage 3.3V
3.201
Output Voltage 3.0V
No Load
Output Voltage 2.5V
VFB
FB Voltage Adjustable version
No Load
IFB
FB Input Current Adjustable
Version
VFB = 1.3V, TAMB = 25°C
2
VOUT Lockout Threshold
Operating Current
IQ
ISHDN
V
2.910
3.0
3.090
V
2.425
2.5
2.575
V
1.212
1.25
1.288
V
1
100
nA
2.15
2.3
V
2.0
2
6
µA
Quiescent Current VOUT
VIN = 5V, VOUT = 3.6V, VFB = 1.3V
20
32
µA
Shutdown Current
EN = 0V, VOUT = 0V, TAMB = +25ºC
0.01
1
µA
MOS Switch Leakage
VIN = 5V, TAMB=25°C, Switches A-D
0.01
1
µA
NMOS B, C
VIN = 5V
0.13
Ω
VIN = 5V
0.17
Ω
VOUT = 3.3V
0.21
Ω
PMOS A
Peak Current Limit
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Enable
VENH
EN Input High
VENL
EN Input Low
EN Input Current
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IEN
3.399
VIN = 5V
PMOS D
IPEAK
Rising Edge
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RON
V
Quiescent Current VIN
Switches
IMOS
3.3
3.30
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VOUT
Output Voltage Adjustable
Version
1.6
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VIN
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Input
L = 6.8µH, VIN = 5V
450
600
750
1.4
EN = 5.5V, TAMB = 25°C
mA
V
0.4
V
1
100
nA
1.25
1.288
V
Low Battery & Power-OK
LBI Threshold
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VLBI
Falling Edge
1.212
LBI Hysteresis
10
LBI Leakage Current
LBO Voltage Low
3
LBI = 5.5V, TAMB = 25°C
ILBO = 1mA
LBO Leakage Current
LBO = 5.5V, TAMB = 25°C
Power-OK Threshold
LBI = 0V, Falling Edge
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Revision 1.04
90
mV
1
100
nA
0.05
0.2
V
1
100
nA
92.5
95
%
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AS1331
Datasheet - E l e c t r i c a l C h a r a c t e r i s t i c s
Table 3. Electrical Characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Thermal Protection
Thermal Shutdown
10°C Hysteresis
145
°C
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1. If the input voltage falls below this value during normal operation the device goes in startup mode.
2. The regulator is in startup mode until this voltage is reached. Caution: Do not apply full load current until the
device output > 2.3V
3. LBO goes low in startup mode as well as during normal operation if:
1) The voltage at the LBI pin is below LBI threshold.
2) The voltage at the LBI pin is below 0.1V and VOUT is below 92.5% of its nominal value.
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Note: All limits are guaranteed. The parameters with min and max values are guaranteed with production tests or
SQC (Statistical Quality Control) methods.
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AS1331
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
7 Typical Operating Characteristics
Circuit of Figure 24 on page 12, VIN = 2.4V, VOUT = 3.3V, TAMB = +25°C, unless otherwise specified.
100
90
90
80
80
60
50
70
60
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Figure 4. Efficiency vs. Output Current; VOUT = 3.0V
100
Efficiency (%)
Efficiency (%)
Figure 3. Efficiency vs. Output Current; VOUT = 2.5V
50
Vi n = 1.8V
40
Vi n = 1.8V
40
Vi n = 3.6V
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Vi n = 3.6V
Vi n = 5.5V
30
Vi n = 5.5V
30
0.1
1
10
100
1000
0.1
Output Current (mA)
100
1000
Figure 6. Efficiency vs. Input Voltage
100
90
90
80
Efficiency (%)
Efficiency (%)
10
Output Current (mA)
Figure 5. Efficiency vs. Output Current; VOUT = 3.3V
100
1
70
60
50
80
70
60
50
Iout = 10mA
Vi n = 1.8V
40
40
Vi n = 3.6V
Iout = 100mA
30
0.1
1
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Vi n = 5.5V
10
100
Iout = 300mA
30
1000
1.8 2.2 2.6 3.0 3.4 3.8 4.2 4.6 5.0 5.4
Output Current (mA)
Figure 8. Sleep Currents vs. Input Voltage
30
25
300
200
100
Sleep Current (µA)
400
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Output Current max (mA)
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500
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Figure 7. IOUT max vs. Input Voltage
Input Voltage (V)
IVOUT
20
15
10
5
IVIN
0
0
1.8 2.2 2.6 3.0 3.4 3.8 4.2 4.6 5.0 5.4
1.8 2.2 2.6 3.0 3.4 3.8 4.2 4.6 5.0 5.4
Input Voltage (V)
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Input Voltage (V)
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AS1331
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
Figure 9. IIN Short Circuit vs. Input Voltage
Figure 10. VOUT Ripple vs. Input Voltage
30
250
20
15
10
5
200
150
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Vout Ripple Voltage (mV)
Input Current (mA)
25
100
50
10uF / Vpp
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22uF / Vpp
47uF / Vpp
0
0
1.8 2.2 2.6 3.0 3.4 3.8 4.2 4.6 5.0 5.4
1.5
2
2.5
3
3.5
4
4.5
5
Figure 11. Load Regulation vs. Load Current
3.38
5.5
Input Voltage (V)
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Input Voltage (V)
Figure 12. VOUT Regulation vs. Temperature
3.5
VOUT = 3.3V
3.25
Output Voltage (V)
Output Voltage (V)
3.36
3.34
3.32
3.3
3.28
3.26
VOUT = 3.0V
3
2.75
VOUT = 2.5V
2.5
2.25
Vout - 10uF
Vout - 22uF
Vout - 47uF
3.24
0.1
1
10
100
2
-45 -30 -15
1000
Load Current (mA)
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Figure 13. IFB vs. Temperature; VIN = 5V
15
30
45
60
75
90
Figure 14. EN Pin Threshold
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0.4
0
Temperature (°C)
3.6V
5.0V
Threshold Voltage (V)
5.5V
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FB Input Current (µA)
0.3
0.2
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0.1
0
0.9
0.8
0.7
-0.1
up-ON
down-OFF
-0.2
-45 -30 -15
0
15
30
45
60
75
90
0.6
-45 -30 -15
Temperature (°C)
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0
15
30
45
60
75
90
Temperature (°C)
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AS1331
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
SW2 SW1
200mA/Div
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VOUT
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5µs/Div
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200mA/Div
ICOIL
200mA/Div
5µs/Div
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5µs/Div
200mV/Div 5V/Div 5V/Div
SW2 SW1
VOUT
200mA/Div
ICOIL
ICOIL
200mV/Div 5V/Div 5V/Div
Figure 20. VIN = 2.5V, VOUT = 3.3V, IOUT = 50mA
200mA/Div
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VOUT
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Figure 19. VIN = 2.5V, VOUT = 3.3V, IOUT = 200mA
5µs/Div
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200mV/Div 5V/Div 5V/Div
VOUT
ICOIL
SW2 SW1
VOUT
ICOIL
SW2 SW1
Figure 18. VIN = 3.6V, VOUT = 3.3V, IOUT = 50mA
200mV/Div 5V/Div 5V/Div
Figure 17. VIN = 3.6V, VOUT = 3.3V, IOUT = 200mA
200mA/Div
SW2 SW1
VOUT
ICOIL
5µs/Div
SW2 SW1
200mV/Div 5V/Div 5V/Div
Figure 16. VIN = 4.4V, VOUT = 3.3V, IOUT = 50mA
200mV/Div 5V/Div 5V/Div
Figure 15. VIN = 4.4V, VOUT = 3.3V, IOUT = 200mA
5µs/Div
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AS1331
Datasheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
2V/Div
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5V/Div
SW2 SW1
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1µs/Div
200mA/Div
VOUT
ICOIL
200mA/Div
200mV/Div
VOUT SW2 SW1
ICOIL
5V/Div
Figure 22. Startup; VIN = 3.6V, Rload = 3.3kΩ
5V/Div 5V/Div
Figure 21. Shorted Output; VIN = 3.6V
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500µs/Div
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AS1331
Datasheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
The synchronous buck-boost converter AS1331 uses a Power Save Mode control technique to reach a high efficiency
over a wide dynamic range of load currents. The output voltage is monitored by a comparator with 3% accuracy. The
Power Save Mode puts the device into “sleep mode” when VOUT is above its programmed reference threshold.
Meaning, the switching is stopped and only quiescent current is drawn from the power source. The switching is started
again when VOUT drops below the reference threshold and the output capacitor is charged again.
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The numbers of current pulses which are necessary to load the output capacitor are set by the value of the output
capacitor, the load current, and the comparator hysteresis (~1%).
Figure 23. AS1331 - Block Diagram - Fixed Output Voltage
SW A
VIN
SW D
Gate Drivers
and
Anticross
Conduction
IZERO
Detect
AS1331
Peak
Current
600mA Limit
SW C
VBEST
VIN
VBEST
State
Machine
and
Logic
VIN
VOUT
FB
UVLO
1.25V
VOUT
Comp
1.6V
EN
VOUT
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SW B
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SW2
SW1
Shutdown
R2
R1
Thermal Shutdown
PGND
GND
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Modes of Operation
When VOUT drops below the reference threshold, the AS1331 switches on the transistors SW A and SW C until the
inductor current reaches approximately 400mA. In the next step SW A and SW D are closed and depending on the
difference between VIN and VOUT the inductor current raises, falls or stays constant.
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VIN > VOUT: The inductor current is going up to 600mA.
VIN ~ VOUT: The device stops after 2µs.
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VIN < VOUT: The inductor current falls down to 0mA.
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If the inductor current is not 0mA, the transistors SW B and SW D are closed to ramp down the current to zero. If VOUT
is still below the threshold voltage the next cycle is started. If IMAX (600mA) wasn’t reached in the previous cycle, SW A
and SW D are closed until the inductor current is 600mA.
Note: The 4-switch-mode (SW A+SW C => SW B+SW D => SW A + SW C...) and also the buck-mode (SW A+SW D
=> SW B+SW D => SW A+SW D...) are never used.
Start-Up Mode
At start-up the switch SW D is disabled and its diode is used to transfer current to the output capacitor until VOUT
reaches approximately 2.15V. The inductor current is controlled by an alternate algorithm during start-up.
Note: Do not apply loads >1mA until VOUT = 2.3V is reached.
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AS1331
Datasheet - D e t a i l e d D e s c r i p t i o n
Other AS1331 Features
Shutdown
The part is in shutdown mode while the voltage at pin EN is below 0.4V and is active when the voltage is higher than
1.4V.
Note: EN can be driven above VIN or VOUT, as long as it is limited to less than 5.5V.
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Output Disconnect and Inrush Limiting
Power-OK and Low-Battery-Detect Functionality
LBO goes low in startup mode as well as during normal operation if:
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During shutdown VOUT is going to 0V so that no current from the input source is running thru the device. The inrush
current is also limited at turn-on mode to minimize the surge currents seen by the input supply. These features of the
AS1331 are realized by opening both P-channel MOSFETs of the rectifiers, allowing a true output disconnect.
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- The voltage at the LBI pin is below LBI threshold (1.25V). This can be used to monitor the battery voltage.
- LBI pin is connected to GND and VOUT is below 92.5% of its nominal value. LBO works as a power-OK signal in
this case.
The LBI pin can be connected to a resistive-divider to monitor a particular definable voltage and compare it with a
1.25V internal reference. If LBI is connected to GND an internal resistive-divider is activated and connected to the
output. Therefore, the Power-OK functionality can be realised with no additional external components.
The Power-OK feature is not active during shutdown and provides a power-on-reset function that can operate down to
VIN = 1.8V. A capacitor to GND may be added to generate a power-on-reset delay. To obtain a logic-level output,
connect a pull-up resistor from pin LBO to pin VOUT. Larger values for this resistor will help to minimize current
consumption; a 100kΩ resistor is perfect for most applications (see Figure 25 on page 12).
For the circuit shown in the left of Figure 24 on page 12, the input bias current into LBI is very low, permitting largevalue resistor-divider networks while maintaining accuracy. Place the resistor-divider network as close to the device as
possible. Use a defined resistor for R5 and then calculate R4 as:
V IN
R 4 = R 5 ⋅ ⎛ ----------- – 1⎞
⎝ V LBI
⎠
Where:
(EQ 1)
VLBI (the internal sense reference voltage) is 1.25V.
Thermal Shutdown
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In case of the LBI pin is connected to GND, an internal resistor-devider network is activated and compares the output
voltage with a 92.5% voltage threshold. For this particular Power-OK application, no external resistive components are
necessary.
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To prevent the AS1331 from short-term misuse and overload conditions the chip includes a thermal overload
protection. To block the normal operation mode all switches will be turned off. The device is in thermal shutdown when
the junction temperature exceeds 145°C. To resume the normal operation the temperature has to drop below 135°C.
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A good thermal path has to be provided to dissipate the heat generated within the package. Otherwise it’s not possible
to operate the AS1331 at its useable maximal power. To dissipate as much heat as possible away from the package
into a copper plane with as much area as possible, it’s recommended to use multiple vias in the printed circuit board.
It’s also recommended to solder the Exposed Pad (pin 11) to the GND plane.
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Note: Continuing operation in thermal overload conditions may damage the device and is considered bad practice.
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AS1331
Datasheet - D e t a i l e d D e s c r i p t i o n
Output Voltage Selection
The AS1331 is available in two versions (see Ordering Information on page 15). One version can only operate at one
fixed output voltage (see Figure 25) and the other version can operate with user-adjustable output voltages from 2.5V
to 3.3V by connecting a voltage divider between the pins VOUT and FB (see Figure 24).
Figure 24. LiIon to Adjustable Output Voltage
4 SW1
2
SW2
5
C1
10µF
8
VIN
R4
LBO
7
AS1331-AD
LBI
R5
VOUT
VOUT
2.5V to 3.3V
R1
10
6
C2
22µF
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On
Off
R3
1
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LiIon Battery
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L1
6.8µH
FB
EN
R2
3
PGND
9 GND
The output voltage can be adjusted by selecting different values for R1 and R2.
Calculate VOUT by:
R1
V OUT = V FB × ⎛ 1 + ------⎞
⎝
R 2⎠
Where:
(EQ 2)
VFB = 1.25V, VOUT = 2.5V to 3.3V;
R2 (the predefined resistor in the resistor devider) should be ≤ 270kΩ.
R3 (the Pull-up resistor for the LBO pin) should be ~100kΩ.
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Figure 25. LiIon to 3.3V with POK - Fixed Output Voltage
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LiIon Battery
4 SW1
2 SW2
5
8
VIN
C1
10µF
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L1
6.8µH
7
LBI
On
Off
LBO
AS13313.3V
C2
22µF
VOUT
3.3V
300mA
FB
EN
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VOUT
10
6
R3
1
3 PGND
9 GND
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AS1331
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9 Application Information
Component Selection
Only three power components are required to complete the design of the buck-boost converter. For the adjustable
version VOUT programming resistors are needed. The high operating frequency and low peak currents of the AS1331
allow the use of low value, low profile inductors and tiny external ceramic capacitors.
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Inductor Selection
For best efficiency, choose an inductor with high frequency core material, such as ferrite, to reduce core losses. The
inductor should have low DCR (DC resistance) to reduce the I²R losses, and must be able to handle the peak inductor
current without saturating. A 6.8µH inductor with a >600mA current rating and <400mΩ DCR is recommended.
L
DCR
LPS3015-682M
6.8µH
300mΩ
0.89A
3.0x3.0x1.5mm
EPL2014-682M
6.8µH
287mΩ
0.80A
2.0x2.0x1.4mm
6.8µH
336mΩ
0.73A
2.0x1.9x1.0mm
XPL2010-682M
Current Rating Dimensions (L/W/T)
Manufacturer
Coilcraft
www.coilcraft.com
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Part Number
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Table 4. Recommended Inductors
Capacitor Selection
The buck-boost convertor requires two capacitors. Ceramic X5R or X7R types will minimize ESL and ESR while
maintaining capacitance at rated voltage over temperature. The VIN capacitor should be at least 2.2µF. The VOUT
capacitor should be between 10µF and 47µF. A larger output capacitor should be used if lower peak to peak output
voltage ripple is desired. A larger output capacitor will also improve load regulation on VOUT. See Table 5 for a list of
capacitors for input and output capacitor selection.
Table 5. Recommended Input Capacitor
Part Number
C
TC Code Rated Voltage
Dimensions (L/W/T)
GRM188R61A225KE34
2.2µF
X5R
10V
0603, T=0.87mm
GRM188R60J475KE19
4.7µF
X5R
6.3V
0603, T=0.87mm
GRM219R60J106KE19
10µF
X5R
6.3V
0805, T=0.95mm
Manufacturer
Murata
www.murata.com
Part Number
ca
Table 6. Recommended Output Capacitor
10µF
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GRM21BR61A106KE19
C
GRM319R61A106KE19
10µF
TC Code Rated Voltage
Dimensions (L/W/T)
X5R
10V
0805, T=1.35mm
X5R
10V
1206, T=0.95mm
10µF
X5R
10V
1210, T=0.95mm
22µF
X5R
16V
1206, T=1.8mm
GRM31CR60J475ME19
47µF
X5R
6.3V
1206, T=1.75mm
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GRM319R61A106KE19
GRM31CR61C226KE15
Manufacturer
Murata
www.murata.com
www.austriamicrosystems.com/DC-DC_Buck-Boost/AS1331
Revision 1.04
13 - 16
AS1331
Datasheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
10 Package Drawings and Markings
The device is available in a 10-pin 3x3mm TDFN package.
Figure 26. 10-pin 3x3mm TDFN package Diagram
D2
SEE
DETAIL B
A
D
D2/2
aaa C
PIN 1 INDEX AREA
(D/2 xE/2)
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2x
E
E2
E2/2
L
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B
K
PIN 1 INDEX AREA
(D/2 xE/2)
aaa C
N N-1
2x
TOP VIEW
bbb
C
C A B
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(ND-1) X e
e
DETAIL B
b
e
ddd
BTM VIEW
Terminal Tip
C
A
A3
ccc C
SEATING
PLANE
SIDE VIEW
A1
0.08 C
Min
Typ
3.00
3.00
Datum A or B
ODD TERMINAL SIDE
Symbol
D BSC
E BSC
D2
E2
L
K
b
e
N
ND
θ
2.20
1.40
0.30
0.20
0.18
0°
0.40
0.25
0.50
10
5
Max
2.70
1.75
0.50
0.30
14°
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Note:
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Table 7. 10-pin 3x3mm TDFN package Dimensions
Symbol
Min
Typ
Max
A
0.70
0.75
0.80
A1
0.00
0.02
0.05
A3
0.20 REF
L1
0.03
0.15
L2
0.13
aaa
0.15
bbb
0.10
ccc
0.10
ddd
0.05
eee
0.08
ggg
0.10
Figure 26 is shown for illustration only.
All dimensions are in millimeters, angle is in degrees.
Dimensioning and tolerancing conform to ASME Y14.5M-1994.
N is the total number of terminals.
Terminal #1 identifier and terminal numbering convention shall conform to JESD 95-1 SPP-012. Details of terminal #1 identifier are optional, but must be located within the area indicated. The terminal #1 identifier may be
either a mold, embedded metal or mark feature.
6. Dimension b applies to metallized terminal and is measured between 0.15 and 0.30mm from terminal tip.
7. ND refers to the maximum number of terminals on D side.
8. Unilateral coplanarity zone applies to the exposed heat sink slug as well as the terminals.
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2.
3.
4.
5.
www.austriamicrosystems.com/DC-DC_Buck-Boost/AS1331
Revision 1.04
14 - 16
AS1331
Datasheet - O r d e r i n g I n f o r m a t i o n
11 Ordering Information
The device is available as the standard products shown in Table 8.
Table 8. Ordering Information
AS1331-BTDT-AD
ASRP
AS1331-BTDT-25*
ASRR
AS1331-BTDT-30*
ASRT
AS1331-BTDT-33
ASRU
Output
Description
300mA Buck-Boost
adjustable Synchronous
DC/DC Converters
300mA Buck-Boost
2.5V
Synchronous DC/DC Converters
300mA Buck-Boost
3.0V
Synchronous DC/DC Converters
300mA Buck-Boost
3.3V
Synchronous DC/DC Converters
* on request
Delivery Form
Package
Tape and Reel 10-pin 3x3mm TDFN
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Marking
Tape and Reel 10-pin 3x3mm TDFN
Tape and Reel 10-pin 3x3mm TDFN
Tape and Reel 10-pin 3x3mm TDFN
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Ordering Code
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Note: All products are RoHS compliant and Pb-free.
Buy our products or get free samples online at ICdirect: http://www.austriamicrosystems.com/ICdirect
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For further information and requests, please contact us mailto:[email protected]
or find your local distributor at http://www.austriamicrosystems.com/distributor
www.austriamicrosystems.com/DC-DC_Buck-Boost/AS1331
Revision 1.04
15 - 16
AS1331
Datasheet
Copyrights
Copyright © 1997-2010, austriamicrosystems AG, Tobelbaderstrasse 30, 8141 Unterpremstaetten, Austria-Europe.
Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged,
translated, stored, or used without the prior written consent of the copyright owner.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
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Disclaimer
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Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding
the information set forth herein or regarding the freedom of the described devices from patent infringement.
austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice.
Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for
current information. This product is intended for use in normal commercial applications. Applications requiring
extended temperature range, unusual environmental requirements, or high reliability applications, such as military,
medical life-support or life-sustaining equipment are specifically not recommended without additional processing by
austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show
deviations from the standard production flow, such as test flow or test location.
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The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However,
austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to
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consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of
austriamicrosystems AG rendering of technical or other services.
Contact Information
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Headquarters
austriamicrosystems AG
Tobelbaderstrasse 30
A-8141 Unterpremstaetten, Austria
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Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
http://www.austriamicrosystems.com/contact
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Revision 1.04
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