as1324-ad austriamicrosystems, as1324-ad Datasheet
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as1324-ad Summary of contents
Page 1
... Typical supply current with no load is 30µA and decreases to ≤1µA in shutdown mode. The AS1324 is available as the standard versions listed in Table 1. Table 1. Standard Versions Model Output Voltage AS1324-AD Adjustable via External Resistors AS1324-12 Fixed: 1.2V AS1324-15 Fixed: 1.5V AS1324-18 Fixed: 1.8V An internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode ...
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... Output Voltage Feedback Pin. An internal resistor divider steps the output voltage down VOUT for comparison to the internal reference voltage. (Fixed voltage variants only.) www.austriamicrosystems.com EN 5 VFB 1 AS1324-12/ AS1324-15/ GND 2 AS1324-18 4 VIN SW 3 Description Revision 1.01 5 VOUT 4 VIN ...
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... AS1324 Data Sheet - Absolute Maximum Ratings Stresses beyond those listed in Table 3 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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... V FB OUT 103 0mA +25ºC OUT AMB Shutdown Mode 0V +25ºC EN AMB AS1324 100mA OUT V = 2. +25ºC AMB 2 AS1324-AD 100mA OUT AS1324-12 100mA OUT AS1324-15 100mA OUT AS1324-18 100mA OUT V = 2 100mA OUT 90%, IN ...
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... AS1324 Data Sheet - Typical Operating Characteristics Parts used for measurement: 4.7µH (MOS6020-472) Inductor, 10µF (GRM188R60J106ME47) C Figure 3. Efficiency vs. Input Voltage 2.7 3.1 3.5 3.9 4.3 Input Voltage (V) Figure 5. Efficiency vs. Output Current ...
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... AS1324 Data Sheet - Figure 9. Switching Frequency vs. Supply Voltage 1.6 1.55 1.5 1.45 1.4 2.7 3.1 3.5 3.9 4.3 Input Voltage (V) Figure 11. Feedback Voltage vs. Temperature 0.61 0.605 0.6 0.595 0.59 -45 -30 - Temperature (C°) Figure 13 1.2V OUT OUT OUTNOM 1 ...
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... AS1324 Data Sheet - Figure 15. Quiescent Current vs. Input Voltage 2.7 3.1 3.5 3.9 4.3 Input Voltage (V) Figure 17. Load Step 0mA to 600mA 500µs/DIV Figure 19. Startup 1ms/DIV www ...
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... Data Sheet - Detailed Description The AS1324 is a high-efficiency buck converter that uses a constant-frequency current-mode architecture. The device contains two internal MOSFET switches and is available in adjustable- and fixed-output voltage versions. Figure 21. Block Diagram ...
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... OSC Shutdown Connecting EN to GND or logic low places the AS1324 in shutdown mode and reduces the supply current to 0.1µA. In shutdown the control circuitry and the internal NMOS and PMOS turn off and SW becomes high impedance discon- necting the input from the output. The output capacitance and load current determine the voltage decay rate. For nor- mal operation connect logic high ...
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... Data Sheet - Application Information The AS1324 is perfect for mobile communications equipment like cell phones and smart phones, digital cameras and camcorders, portabel MP3 and DVD players, PDA’s and palmtop computers and any other handheld instruments. ...
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... Note: For highest efficiency, a low DC-resistance inductor is recommended. Accepting larger values of ripple current allows the use of low inductance values, but results in higher output voltage ripple, greater core losses, and lower output current capability. www.austriamicrosystems.com 4.7µ AS1324 OUT GND 2 V ...
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... Output Current (mA) Output Capacitor Selection The advanced fast-response voltage mode control scheme of the AS1324 allows the use of tiny ceramic capacitors. Because of their lowest output voltage ripple low ESR ceramic capacitors are recommended. X7R or X5R dielectric output capacitor are recommended. At high load currents, the device operates in PWM mode and the RMS ripple current is calculated as: ...
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... Because ceramic capacitors lose a lot of their initial capacitance at their maximum rated voltage recommended that either a higher input capacity or a capacitance with a higher rated voltage is used. Feedback Resistor Selection In the AS1324-AD, the output voltage is set by an external resistor divider connected to V cuitry allows for remote voltage sensing and adjustment. www.austriamicrosystems.com × ...
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... A higher resistance of R ommended to keep V 500mV higher than V IN Efficiency The efficiency of a switching regulator is equivalent to: For optimum design, an analysis of the AS1324 is needed to determine efficiency limitations and to determine design changes for improved efficiency. Efficiency can be expressed as: Efficiency = 100% – (L Where etc ...
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... Due to its high-efficiency design, the AS1324 will not dissipate much heat in most applications. However, in applica- tions where the AS1324 is running at high ambient temperature, uses a low supply voltage, and runs with high duty cycles (such as in dropout) the heat dissipated may exceed the maximum junction temperature of the device. ...
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... RMS current rating of at least 0.3A 0.25 Ω most cases, a ceramic capacitor will satisfy this requirement. For the feedback resistors, select the value for R Layout Considerations The AS1324 requires proper layout and design techniques for optimum performance. ! The power traces (GND, SW, and V ! ...
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... AS1324 Data Sheet - Figure 31. AS1324-18 Basic PCB Layout V OUT Figure 32. AS1324-18 Basic Diagram V OUT www.austriamicrosystems.com Via AS1324 OUT IN GND VOUT AS1324-18 2 GND ...
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... AS1324 Data Sheet - Package Drawings and Markings The device is available in an 5-pin TSOT-23 package. Figure 33. 5-pin TSOT-23 Package Symbol Min Typ A A1 0.01 0.05 A2 0.84 0.87 b 0.30 b1 0.31 0.35 c 0.12 0.15 c1 0.08 0.13 D 2.90BSC E 2.80BSC E1 1.60BSC e 0 ...
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... High-efficiency, constant-frequency synchronous AS1324-BTTT-12 ASKT buck converter; fixed output voltage (1.2V). High-efficiency, constant-frequency synchronous AS1324-BTTT-15 ASKU buck converter; fixed output voltage (1.5V). High-efficiency, constant-frequency synchronous AS1324-BTTT-18 ASKS buck converter; fixed output voltage (1.8V). www.austriamicrosystems.com Description Delivery Form Revision 1.01 Package T&R 5-pin TSOT-23 T& ...
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... AS1324 Data Sheet Copyrights Copyright © 1997-2008, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, trans- lated, 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. ...