AMS AS1340 Power Management Datasheet
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Reklama
AS1340
50V, Micropower, DC-DC Boost Converter
1 General Description
The AS1340 boost converter contains a 1.4A internal switch in a tiny
TDFN-8 3x3mm package. The device operates from a 2.7 to 5.5V supply, and can boost voltages up to 50V output.
The output voltage can easily be adjusted by an external resistor divider.
The AS1340 uses a unique control scheme providing the highest efficiency over a wide range of load conditions. An internal 1.4A
MOSFET reduces external component count, and a fixed high switching frequency (1MHz) allows for tiny surface-mount components.
The AS1340 also features power-OK circuitry which monitors the output voltage.
Additionally the AS1340 features a low quiescent supply current and a shutdown mode to save power. During shutdown an output disconnect switch separates the input from the output.
The AS1340 is ideal for LCD or OLED panels with low current requirements and can also be used in a wide range of other applications.
The device is available in a low-profile TDFN-8 3x3mm package.
2 Key Features
2.7V to 50V Adjustable Output Voltage
2.7V to 50V Input Voltage Range
2.7V to 5.5V Supply Voltage Range
High Output Currents:
- 100mA @ 12V from 3.3V V
IN
- 50mA @ 24V from 3.3V V
IN
- 30mA @ 36V from 3.3V V
IN
Efficiency: Up to 93%
Switching Frequency: 1MHz
Output Disconnect
Power-OK Output
Operating Supply Current: 30µA
Shutdown Current: 0.1µA
TDFN-8 3x3mm Package
3 Applications
The device is ideal for OLED display power supply, LED power supply, LCD bias generators, mobile/cordless phones, palmtop computers, PDAs and organizers, handy terminals or any other portable, battery-powered device.
Figure 1. AS1340 - Typical Application Diagram
V
IN
= 2.7V to 5.5V
C
IN
On
Off
2
VCC
4
POK
1
EN
3
SWVIN
AS1340
6
SWOUT
L
1
4.7µH
V
IN
= 2.7V to
5.5V
5
LX
8
FB
7, 9
GND
V
OUT
= > V
IN
to 50V
R
R
1
2
VCC
C
OUT
V
IN
= 2.7V to
~V
OUT
V
IN
= 2.7V to
5.5V
VCC
3
L
1
6
LX
3
L
1
6
LX
V
OUT
V
OUT
If not needed the output disconnect switch can be left unconnected which will also increase the efficiency.
Additionally the supply of the chip can be split to allow higher supply voltages for the coil. In this case the output disconnect switch must not be used.
www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
Datasheet - P i n A s s i g n m e n t s
4 Pin Assignments
Figure 2. Pin Assignments (Top View)
EN 1
VCC
2
SWVIN 3
POK 4
8 FB
AS1340
7 GND
6 SWOUT
GND 9
5 LX
4.1 Pin Descriptions
Table 1. Pin Descriptions
Pin Number Pin Name
1
2
3
4
EN
VCC
SWVIN
POK
8
9
5
6
7
LX
SWOUT
GND
FB
GND
Description
Active-High Enable Input. A logic low on this pin shuts down the device and reduces the supply current to 0.1µA.
Note:
Connect to V
CC
for normal operation.
+2.7V to +5.5V Supply Voltage. Bypass this pin to GND with a
1µF capacitor.
Shutdown Disconnect Switch In
Power-OK.
0 = V
OUT
< 90% of V
OUTNOM
.
1 = V
OUT
> 90% of V
OUTNOM
.
Inductor. The drain of the internal N-channel MOSFET.
Note:
This pin is high impedance in shutdown.
Shutdown Disconnect Switch Out. Disconnects the input from the output during shutdown.
Ground. This pin and pin 9 must be connected to GND to ensure normal operation.
Feedback Pin. Feedback input to the g m
error amplifier. Connect a resistor divider tap to this pin. The output voltage can be adjusted from V
IN
to 50V by:
V
OUT
= 1.25V[1 + (R
1
/R
2
)]
Ground. This pin and pin 7 must be connected to GND to ensure normal operation.
www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
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.
Table 2. Absolute Maximum Ratings
Parameter
Electrical Parameters
VCC, FB, EN to GND
SWVIN, SWOUT to GND
LX to GND
Input Current (latch-up immunity)
Electrostatic Discharge
Electrostatic Discharge HBM
Temperature Ranges and Storage Conditions
Thermal Resistance
JA
Junction Temperature
Storage Temperature Range
Min
-0.3
-0.3
-100
-55
1.5
36.7
Max
7
7
55
100
+150
+125
Units
V mA kV
ºC/W
ºC
ºC
Comments
Norm: JEDEC 78
Norm: MIL 883 E method 3015 on PCB
Package Body Temperature
+260
ºC
The reflow peak soldering temperature (body temperature) specified is in accordance with IPC/
JEDEC J-STD-020“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).
Humidity non-condensing
Moisture Sensitive Level
5
1
85 %
Represents a max. floor life time of unlimited www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
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
V
CC
= EN = 2.7V, T
AMB
= -40 to +85ºC (unless otherwise specified). Typical values are at T
AMB
= +25ºC.
Table 3. Electrical Characteristics
Symbol Parameter
T
AMB
Operating Range
V
CC
Supply
V
IN
V
OUT
Inductor Input Voltage Range
Output Voltage Range
I
CC
Current
Enable Supply Current
V
LNR
V
V
CC
IN
Line Regulation
Line Regulation
V
FB
= 1.3V, V
IN
= 5V
EN = GND
V
OUT
= 18V, I
LOAD
= 1mA, V
IN
= 5.5V,
V
CC
= 2.7 to 5.5V
V
OUT
= 18V, I
LOAD
= 1mA,
V
CC
= 5V, V
IN
= 2.7 to 5.5V
V
LDR
Load Regulation
Efficiency
V
OUT
= 18V, V
CC
= V
IN
= 5V, I
LOAD
= 0 to
20mA
L
1
= 10µH, V
IN
= 5.5V, V
OUT
100mA
= 20V, I
LOAD
=
V
FB
Feedback Set Point
I
FB
DC-DC Switches
Feedback Input Bias Current
I
LX(MAX)
V
OUT
max
LX Switch Current Limit
R
LX
LX
R
P_ON
I
LX_LEAK
I
P_LEAK
Control Inputs
Switch On-Resistance
LX Leakage Current
Switch Leakage Current
V
V
V
IN
IN
Condition
V
FB
= 5.5V, I
CC
= 1.3V
= 5.5V, I
V
LOAD
LOAD
= 5.5V, I
V
IN
IN
LX
= 0mA
> 20mA
= 100mA
= 5.5V, PMOS
V
LX
= 50V
= 5.5V, PMOS
Min
-40
2.7
2.7
2.7
Typ
30
0.1
0.3
50
1.41
0.6
0.2
2
0.5
Max
+85
50
50
50
1
Unit
°C
V
V
µA
µA
%/V
0.25 %/V
0.02
%/mA
88 %
1.225 1.25 1.275
5 100
V nA
V
A
µA
V
IH
0.8 x
V
CC
EN Input Threshold 2.7V
V
CC
5.5V V
V
IL
EN Input Bias Current V
CC
= 5.5V, V
EN
= 0 to 5.5V
-1
0.2 x
V
CC
+1 µA I
EN
POK Output
V
OL
POK Output Low Voltage
POK Output High Leakage Current
POK Threshold
POK sinking 1mA
POK = 5.5V
Rising edge, referenced to V
OUT(NOM)
87
0.01
100
90
0.2
500
93
V nA
%
Oscillator
f
CLK
Oscillator Frequency
Maximum Duty Cycle
0.85
85
1
90
1.15
95
MHz
%
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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AS1340
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
Parts used for measurements: 4.7µH (LPS4018-472ML) Inductor, 10µF (GRM32DR71C106KA01) C
IN
and 1µF (GRM31MR71H105KA88)
C
OUT.
Figure 3. Efficiency vs. Output Current; V
OUT
= 36V
100
90
Figure 4. Efficiency vs. Output Current; V
OUT
= 24V
100
90
80
70
60
50
40
30
20
10
0
0.1
1 10
Output Current (mA)
Figure 5. Efficiency vs. Output Current; V
OUT
= 12V
100
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
100
90
80
70
60
50
40
30
20
10
0
0.1
1 10
Output Current (mA)
Figure 7. Efficiency vs. V
IN
; V
OUT
=18V, Split Supplies
100
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
100
80
70
60
50
40
30
20
10
0
0.1
1 10
Output Current (mA)
Figure 6. Efficiency vs. Output Current; V
OUT
= 6V
100
90
80
70
60
50
40
30
20
10
0
0.1
1 10
Output Current (mA)
Figure 8. Efficiency vs. V
IN
; I
OUT
= 10mA
100
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
100
100
90 90
80 80
70 70
60 60
50
Iout = 1mA
Iout = 10mA
Iout = 50mA
40
2 4 6 8
Input Voltage (V) www.ams.com/DC-DC_Step-Up/AS1340
Iout = 5mA
Iout = 20mA
10 12
50
Vout = 6V
Vout = 18V
Vout = 30V
Vout = 48V
Vout = 12V
Vout = 24V
Vout = 36V
40
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
Input Voltage (V)
Revision 1.20
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AS1340
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. Output Voltage vs. Temperature;
V
OUT
= 18V
18.5
18.4
18.3
18.2
Iout =1mA
Iout =5mA
Iout =10mA
Iout =20mA
Iout =50mA
18.1
18
17.9
17.8
17.7
17.6
17.5
-45 -30 -15 0 15 30 45 60 75 90
Temperature (C°)
Figure 10. Output Voltage vs. Load Current;
V
OUT
= 18V, V
IN
= 3.3V
18.5
18.4
18.3
18.2
18.1
18
17.9
17.8
17.7
17.6
17.5
0 10 20
Output Current (mA)
30 40
Figure 11. Output Voltage vs. Input Voltage;
V
OUT
= 18V, Split Supplies
18.5
18.4
18.3
18.2
18.1
18
17.9
17.8
17.7
17.6
17.5
Iout = 1mA
Iout = 5mA
Iout = 10mA
Iout = 20mA
2 3 4 5 6 7 8 9 10 11 12
Input Voltage (V)
Figure 12. Output Voltage vs. Input Voltage;
V
OUT
= 18V
18.5
18.4
18.3
18.2
18.1
18
17.9
17.8
17.7
17.6
Iout = 1mA
Iout = 5mA
Iout = 10mA
Iout = 20mA
17.5
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
Input Voltage (V)
Figure 13. Output Current vs. V
IN
; Split Supplies
500
450
Vout = 12V
Vout = 24V
Vout = 36V
Vout = 18V
Vout = 30V
400
350
300
250
200
150
100
50
0
2 3 4 5 6 7 8 9 10 11 12
Input Voltage (V)
Figure 14. Output Current vs. V
IN
500
450
Vout = 12V
Vout = 24V
Vout = 36V
400
350
300
Vout = 18V
Vout = 30V
250
200
150
100
50
0
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
Input Voltage (V) www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
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 15. Startup Voltage vs. Output Current;
V
IN
= 2.7 to 5.5V
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
Vout = 6V
Vout = 18V
Vout = 30V
Vout = 12V
Vout = 24V
Vout = 36V
0 5 10 15 20 25 30 35 40 45 50
Output Current (mA)
Figure 16. Input Current vs. Input Voltage;
I
OUT
= 0mA, switching
1
0.9
0.8
0.7
0.6
Vout = 6V
Vout = 12V
Vout = 18V
Vout = 24V
Vout = 30V
0.5
0.4
0.3
0.2
0.1
0
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
Input Voltage (V)
Figure 17. Input Current vs. Output Current;
V
OUT
= 12V
600
500
Vi n = 2.4V
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
400
300
200
100
0
0 10 20 30 40 50
Output Current (mA)
60 70
Figure 18. Input Current vs. Output Current;
V
OUT
= 18V
600
500
Vi n = 2.4V
Vi n = 2.7V
Vi n = 3.3V
Vi n = 5.5V
400
300
200
100
0
0 10 20 30 40 50
Output Current (mA)
60 70
Figure 19. Startup Waveform Figure 20. Startup Waveform - POK
200µs/Div www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
50µs/Div
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AS1340
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 21. Transient Line Regulation;
V
OUT
= 18V, I
LOAD
= 1mA
Figure 22. Transient Line Regulation;
V
OUT
= 18V, I
LOAD
= 20mA
500µs/Div
Figure 23. Output Voltage Ripple;
V
OUT
= 18V, I
OUT
= 1mA
V
IN
= 5.5V
V
IN
= 3.3V
V
IN
= 2.7V
1µs/Div
Figure 25. Load Transient Response;
V
IN
= 5.5V, V
OUT
= 18V
500µs/Div
Figure 24. Output Voltage Ripple;
V
OUT
= 18V, I
OUT
= 20mA
V
IN
= 5.5V
V
IN
= 3.3V
V
IN
= 2.7V
2ms/Div
Figure 26. Fixed Frequency vs. Powersave Operation;
V
IN
= 2.7V, V
OUT
= 18V
2ms/Div www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
2ms/Div
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AS1340
Datasheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
The AS1340 features a current limiting circuitry, a fixed-frequency PWM architecture, power-OK circuitry, thermal protection, and an automatic powersave mode in a tiny package, and maintains high efficiency at light loads.
Figure 27. AS1340 - Block Diagram with Shutdown Disconnect Switch
V
IN
= 2.7V to 5.5V
2
VCC
C
IN
1µF
1
EN
3 SWVIN 6 SWOUT
L
1
4.7µH
4 POK
PWM
Control
1 MHz
Spread
Spectrum
Ramp Generator
PWM
Comp
+
–
–
Shutdown
Control
Shutdown
Slope
Compensator
R
C
C
C
Powersave
Powersave
Operation
Control
Sync Drive
Control
C
P2
5 LX
V
OUT
Good
–
+
0.9
Current
Sense
V
C
AS1340
– g m
Error
Amp
+
1.13V
8
FB
C
FF
*
1.25V
Ref
7,9
GND
R
1
R
2
V
IN
to 50V
C
OUT
* Optional
Automatic powersave mode regulates the output and also reduces average current flow into the device, resulting in high efficiency at light loads.
When the output increases sufficiently, the powersave comparator output remains high, resulting in continuous operation.
For each oscillator cycle, the power switch is enabled. A voltage proportional to switch current is added to a stabilizing ramp and the resulting sum is delivered to the positive terminal of the PWM comparator.
The error amplifier compares the voltage at FB with the internal 1.25V reference and generates an error signal (V
C
). When V
C
is below the powersave mode threshold voltage the automatic powersave-mode is activated and the hysteretic comparator disables the power circuitry, with only the low-power circuitry still active (total current consumption is minimized).
When a load is applied, V
FB
decreases; V
C
increases and enables the power circuitry and the device starts switching. In light loads, the output voltage (and the voltage at FB) will increase until the powersave comparator disables the power circuitry, causing the output voltage to decrease again. This cycle is repeated resulting in low-frequency ripple at the output.
The POK output indicates whether the output voltage is within 90% of the nominal output voltage level or not. When EN is low, the circuit is not active and POK gives a high signal when connected to V
CC
by a pull-up resistor. When EN goes high, POK goes low after approximately 50µs and will go high when the output reaches 90% of the nominal output voltage
. When input and output voltage are almost the same, it may happen that the POK Signal does not go low because V
OUT
reaches 90% before the delay has expired. The open-drain
POK output sinks current, when EN is high and the output voltage is below 90% of the nominal output voltage.
Thermal protection circuitry shuts down the device when its temperature reaches 145ºC.
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AS1340
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
9.1 Power Supply Concept
The AS1340 has an operating voltage range from 2.7 to 5.5V. If the inductor is supplied from the same source the battery disconnect switch can be used as well
9.2 Shutdown
A logic low on pin EN shuts down the AS1340 and a logic high on EN powers on the device.
In shutdown mode the supply current drops to below 1µA to maximize battery life. In case that the battery disconnect switch is used, the battery is disconnected from the output during shutdown.
Note:
Pin EN should not be left floating. If the shutdown feature is not used, connect EN to V
IN
.
9.3 Battery Disconnect
The AS1340 has an integrated switch that can be used to disconnect the battery during shutdown. The operation voltage of this switch is limited to 5.5V. When EN is high, the switch is closed and supplies the inductor. Due to the R
ON
resistance the efficiency is slightly lower if the battery disconnect switch is used.
P
LOSS
= I
IN
² x R
ON
(EQ 1)
9.4 Setting Output Voltage
Output voltage can be adjusted by connecting a voltage divider between pins LX and FB
Figure 28. Typical Application (SWVIN and SWOUT not in use)
Supply
2.7V to
V
OUT
C
IN
10µF
V
IN
= 2.7V to 5.5V
C
1
0.1µF
2
VCC
3
SWVIN
6
SWOUT
L
1
4.7µH
C
OUT
1µF
V
OUT
= 18V
On
Off
4
POK
1
EN
AS1340
D1
5
LX
R
1
2.2M
8
FB
R
2
165k
7,9
GND
The output voltage can be adjusted by selecting different values for R
1
and R
2
. For R
2
, select a value between 10k and 200k
.
Calculate R
1
by:
R
1
=
R
2
V
-------------
– 1
V
FB
(EQ 2)
Where:
V
OUT
= V
IN
to 50V, V
FB
= 1.25V
The input bias current of FB has a maximum value of 100nA which allows for large-value resistors. For less than 1% error, the current through R
2 should be 100 times the feedback input bias current (I
FB
).
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AS1340
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.5 LED Power Supply Application
.
Figure 29. LED Supply Application
V
IN
= 2.7V to 5.5V
C
0.1µF
2
VCC
3
SWVIN
6
SWOUT
L
1
4.7µH
AS1340
On
Off
4
POK
1
EN
5
LX
D1
8
FB
R
2
100
I
LED
7,9
GND
C
OUT
1µF
The output voltage is adjusted automatically to the required voltage of the LEDs. This voltage depends on the forward voltage (V
F
LEDs and the Feedback Voltage V
FB
.
) of the used
Calculate V
OUT
by:
V
OUT
=
V
F
I
LED
n
+
V
FB
(EQ 3)
Note:
The brightness of the LEDs can directly be adjusted by setting the current I
LED
via the corresponding R
2
.
Calculate R
2
by:
I
LED
=
V
FB
R
2
(EQ 4)
Where:
V
FB
= 1.25V
n .... number of LED’s www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.6 Inductor Selection
For the external inductor, a 6.8µH inductor is recommended. Minimum inductor size is dependant on the desired efficiency and output current.
Inductors with low core losses and small DCR at 1MHz are recommended.
Table 4. Recommended Inductors
Part Number
LPS4018-472ML_
ME3220-472ML_
MOS6020-472ML_
MSS6122-472ML_
LPS4018-682ML_
ME3220-682ML_
MOS6020-682ML_
MSS6122-682ML_
L
4.7µH
4.7µH
4.7µH
4.7µH
6.8µH
6.8µH
6.8µH
6.8µH
DCR
0.125
0.190
0.050
0.065
0.150
0.270
0.078
0.100
Current Rating
1.9A
1.5A
1.94A
1.82A
1.3A
1.2A
1.72A
1.50A
Dimensions (L/W/T)
4.4x4.4x1.7mm
3.2x2.8x2mm
6.8x6x2.4mm
6.1x6.1x6mm
4.4x4.4x1.7mm
3.2x2.8x2mm
6.8x6x2.4mm
6.1x6.1x6mm
Manufacturer
Coilcraft www.coilcraft.com
30
20
10
0
70
60
50
40
1
Figure 30. Efficiency Comparison of Different Inductors, V
IN
= 3.3V, V
OUT
= 18V
100
90
100
90
80 80
10
Output Current (mA)
LPS4018-472
LPS4018-682
ME3220-472
ME3220-682
100
30
20
10
0
70
60
50
40
1 10
Output Current (mA)
MOS6020-472
MOS6020-682
MSS6122-472
MSS6122-682
100
30
20
10
0
70
60
50
40
1
Figure 31. Efficiency Comparison of Different Inductors, V
IN
= 5.5V, V
OUT
= 18V
100
90
100
90
80 80
10
Output Current (mA)
LPS4018-472
LPS4018-682
ME3220-472
ME3220-682
100
70
60
50
40
30
20
10
0
1 10
Output Current (mA)
MOS6020-472
MOS6020-682
MSS6122-472
MSS6122-472
100 www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.7 Capacitor Selection
A 4.7µF capacitor is recommended for C
IN
as well as a 2µF for C
OUT
. Small-sized ceramic capacitors are recommended. X5R and X7R ceramic capacitors are recommend as they retain capacitance over wide ranges of voltages and temperatures.
9.7.1 Output Capacitor Selection
Low ESR capacitors should be used to minimize V
OUT
ripple. Multi-layer ceramic capacitors are recommended since they have extremely low
ESR and are available in small footprints. A 2.2 to 10µF output capacitor is sufficient for most applications. Larger values up to 22µF may be used to obtain extremely low output voltage ripple and improve transient response.
X5R and X7R dielectric materials are recommended due to their ability to maintain capacitance over wide voltage and temperature ranges.
Table 5. Recommended Output Capacitor
Part Number
GRM31MR71H105KA88
GRM32ER71H475KA88
C1206C105K5RAC
C1206C225K5RAC
C
1µF
4.7µF
1µF
2.2µF
1206C105KAT2A 1µF
TC Code
X7R
X7R
X7R
X7R
X7R
Rated Voltage
50V
50V
50V
50V
50V
Dimensions (L/W/T)
C1206
C1210
C1206
C1210
C1206
Manufacturer
Murata www.murata.com
Kemet www.kemet.com
AVX www.avx.com
9.7.2 Input Capacitor Selection
Low ESR input capacitors reduce input switching noise and reduce the peak current drawn from the battery. Ceramic capacitors are recommended for input decoupling and should be located as close to the device as is practical. A 4.7µF input capacitor is sufficient for most applications. Larger values may be used without limitations.
Table 6. Recommended Input Capacitor
Part Number
GRM21BR71C105KA01
GRM21BR61C225KA88
GRM32DR71C106KA01
C
1µF
2.2µF
10µF
TC Code
X7R
X7R
X7R
Rated Voltage
16V
16V
16V
Dimensions (L/W/T)
C0805
C0805
C1210
Manufacturer
Murata www.murata.com
9.7.3 Diode Selection
A Schottky diode must be used to carry the output current for the time it takes the PMOS synchronous rectifier to switch on.
Note:
Do not use ordinary rectifier diodes, since the slow recovery times will compromise efficiency.
Table 7. Recommended Diodes
Part Number Reverse Voltage Forward Current Package
PMEG4010BEA
MBR0540
MBR0560
40V
40V
60V
1A
500mA
500mA
SOD123
SOD123
SOD123
Manufacturer
Philips www.nxp.com
MCC www.mccsemi.com
9.8 Thermal Protection
To protect the device from short circuit or excessive power dissipation of the auxiliary NPNs, the integrated thermal protection switches off the device when the junction temperature (T
J
) reaches 145ºC (typ). When T
J
decreases to approximately 125ºC, the device will resume normal operation. If the thermal overload condition is not corrected, the device will switch on and off while maintaining T
J
within the range between
125ºC and 145ºC.
www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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AS1340
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
Figure 32. TDFN-8 3x3mm Marking
Package Code:
XXXX - encoded Datecode www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
14 - 17
AS1340
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
Figure 33. TDFN-8 3x3mm Package
www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
15 - 17
AS1340
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. Ordering Information
Ordering Code
AS1340A-BTDT-10
Marking
ASM3
Description
50V, Micropower, DC-DC Boost Converter,
Automatic Power Save, 1MHz
Note:
All products are RoHS compliant.
Buy our products or get free samples online at ICdirect: http://www.ams.com/ICdirect
Technical Support is found at http://www.ams.com/Technical-Support
For further information and requests, please contact us mailto:[email protected]
or find your local distributor at http://www.ams.com/distributor
Delivery Form
Tape and Reel
Package
TDFN-8 3x3mm www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
16 - 17
AS1340
Datasheet
Copyrights
Copyright © 1997-2010, ams 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.
Disclaimer
Devices sold by ams AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. ams 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. ams 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 ams 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 ams 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.
The information furnished here by ams AG is believed to be correct and accurate. However, ams AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or 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 ams AG rendering of technical or other services.
Contact Information
Headquarters
ams AG
Tobelbaderstrasse 30
A-8141 Unterpremstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit: http://www.ams.com/contact www.ams.com/DC-DC_Step-Up/AS1340 Revision 1.20
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