as1331 austriamicrosystems, as1331 Datasheet
as1331
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as1331 Summary of contents
Page 1
... This special device is a synchronous buck-boost DC/DC converter which can handle input voltages above, below, or equal to the output voltage. 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. ...
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... SW2 5 VIN EN 6 LBI 7 LBO 8 GND www.austriamicrosystems.com VOUT AS1331 SW2 2 GND 9 TDFN (3x3) PGND 3 LBO 8 10-pin SW1 4 LBI 7 VIN 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. ...
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... AS1331 Data Sheet - Absolute Maximum Ratings Stresses beyond those listed in Table 2 and functional operation of the device at these or any other conditions beyond those indicated in Characteristics on page 4 is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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... AS1331 Data Sheet - Electrical Characteristics V = 3.6V 3.3V -40°C to +85ºC. Typical values are OUT AMB Table 3. Electrical Characteristics Symbol Parameter Input V Input Voltage Range IN Minimum Startup Voltage ...
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... AS1331 Data Sheet - Table 3. Electrical Characteristics Symbol Parameter Thermal Protection Thermal Shutdown 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 > ...
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... AS1331 Data Sheet - Typical Operating Characteristics Circuit of Figure 24 on page 12 2.4V Figure 3. Efficiency vs. Output Current; V 100 0 Output Current (mA) Figure 5. Efficiency vs. Output Current; V ...
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... AS1331 Data Sheet - Figure 9. I Short Circuit vs. Input Voltage 1.8 2.2 2.6 3.0 3.4 3.8 4.2 4.6 5.0 5.4 Input Voltage (V) Figure 11. Load Regulation vs. Load Current 3.38 3.36 3.34 3.32 3.3 3.28 3.26 3.24 0 Load Current (mA) Figure 13. I vs. Temperature; V ...
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... AS1331 Data Sheet - Figure 15 4.4V 3.3V OUT OUT 5µs/Div Figure 17 3.6V 3.3V OUT OUT 5µs/Div Figure 19 2.5V 3.3V OUT OUT 5µs/Div www.austriamicrosystems.com = 200mA Figure 16 ...
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... AS1331 Data Sheet - Figure 21. Shorted Output 3.6V IN 1µs/Div www.austriamicrosystems.com Figure 22. Startup 3.6V 500µs/Div Revision 1.02 = 3.3kΩ load ...
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... EN Shutdown Modes of Operation When V drops below the reference threshold, the AS1331 switches on the transistors SW A and SW C until the OUT inductor current reaches approximately 400mA. In the next step SW A and SW D are closed and depending on the difference between V and V the inductor current raises, falls or stays constant. ...
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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. ...
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... AS1331 Data Sheet - Output Voltage Selection The AS1331 is available in two versions 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 Figure 24 ...
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... Only three power components are required to complete the design of the buck-boost converter. For the adjustable version V programming resistors are needed. The high operating frequency and low peak currents of the AS1331 OUT allow the use of low value, low profile inductors and tiny external ceramic capacitors. ...
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... AS1331 Data Sheet - Package Drawings and Markings The device is available in a 10-pin 3x3mm TDFN package. Figure 26. 10-pin 3x3mm TDFN package Diagram D PIN 1 INDEX AREA aaa C 2x (D/2 xE/2) 4 TOP VIEW ...
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... Table 8. Ordering Information Part Number Marking Output AS1331-BTDT-AD ASRP adjustable AS1331-BTDT-25* ASRR 2.5V AS1331-BTDT-30* ASRT 3.0V AS1331-BTDT-33 ASRU 3. request All devices are RoHS compliant and free of halogene substances. www.austriamicrosystems.com Table 8. Description Delivery Form 300mA Buck-Boost Synchronous DC/DC Converters Tape and Reel 10-pin 3x3mm TDFN 300mA Buck-Boost ...
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... AS1331 Data Sheet Copyrights Copyright © 1997-2009, austriamicrosystems AG, Schloss Premstaetten, 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. ...