AAT3131_08 ANALOGICTECH [Advanced Analogic Technologies], AAT3131_08 Datasheet
AAT3131_08
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AAT3131_08 Summary of contents
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General Description The AAT3131 is a low noise, constant frequency charge pump DC/DC converter that uses a dual mode load switch (1X) and fractional (1.5X) con- version to maximize efficiency for white LED appli- cations. The device can be used ...
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Pin Descriptions Pin # Symbol Function 1 C2+ Flying capacitor 2 positive terminal. Connect a 1µF capacitor between C2+ and C2-. 2 OUT Charge pump output. Requires 1µF capacitor connected between this pin and ground. 3 C1- Flying capacitor 1 ...
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Absolute Maximum Ratings Symbol Description V Input Voltage IN V Charge Pump Output OUT EN/SET to GND Voltage B EN/SET V Maximum EN/SET to Input Voltage EN/SET(MAX Maximum DC Output Current OUT T ...
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Electrical Characteristics V = 3.5V 1.0µ OUT 1 2 Symbol Description Input Power Supply V Operation Range IN I Operating Current CC I Shutdown Current SHDN Maximum Output Current ...
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Typical Characteristics Unless otherwise noted 3.5V Efficiency vs. Input Voltage (4x20mA) 100 3.3V 90 DIODE 3.4V DIODE DIODE 65 V DIODE 2.7 2.9 ...
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Typical Characteristics Unless otherwise noted 3.5V Turn-On to Full-Scale Charge Pump ENSET (1V/div) OUT (2V/div) V DIODE (1V/div (200mA/div) Time (50µs/div) Charge Pump to Load Switch (80mA (10mV/div) OUT (2V/div) V DIODE ...
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Functional Block Diagram EN/SET Functional Description The AAT3131 is a dual mode load switch (1X) and high efficiency (1.5X) fractional charge pump device intended for white LED backlight applica- tions. The fractional charge pump consists of a low dropout linear ...
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can be controlled inde- pendently of output D4. For Addresses 16 24, and 25 to 32, outputs start at 0mA and increase from 0.5mA ...
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Current Level Settings (mA) Address D1-3 1 0.0 2 0.5 3 1.3 4 3.3 5 8.3 6 11.1 7 15.0 8 20.0 9 0.0 10 0.5 11 1.3 12 3.3 13 8.3 14 11.1 15 15.0 16 20.0 17 0.0 ...
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EN/SET Timing Diagram EN/SET Code OFF LED Selection The AAT3131 is specifically intended for driving white LEDs. However, the device design will allow the AAT3131 to drive most types of LEDs with for- ward voltage specifications ranging from 2.0V to ...
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Refer to the following two sections for explanations for each operational mode. Load Switch Mode Efficiency The AAT3131 load switch mode is operational at all times and functions alone to enhance device power conversion efficiency when V ...
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Equivalent Series Resistance ESR is an important characteristic to consider when selecting a capacitor. ESR is a resistance internal to a capacitor that is caused by the leads, internal connections, size or area, material composition, and ambient temperature. Capacitor ESR ...
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BATTERY 1µF EN/SET *In some applications, white LED forward voltages (V for balancing the forward voltage differences. The ballast resistor value may be approximated by the following equation: Figure 2: AAT3131 Driving Two Groups of Paralleled White ...
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Ordering Information Package TSOPJW-12 All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For ...