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Lithium Ion Linear Charge Controllers - 34026 AAT2550178

TM

Total Power Solution for Portable ApplicationsSystemPower

General Description Features

The AAT2550 is a fully integrated total power solution with two step-down converters plus a single-cell lithium-ion / polymer battery charger. The step-down converter input voltage range spans 2.7V to 5.5V, making the AAT2550 ideal for systems powered by single-cell lithi-um-ion/polymer batteries.The battery charger is a complete constant current/ con-stant voltage linear charger. It offers an integrated pass device, reverse blocking protection, high current accu- racy and voltage regulation, charge status, and charge termination. The charging current is programmable via external resistor from 100mA to 1A. In addition to these standard features, the device offers over-voltage, over-current, and thermal protection.The two step-down converters are highly integrated, operating at a switching frequency of 1.4MHz, minimiz- ing the size of external components while keeping switching losses low. Each converter has independent input, enable, and feedback pins. The output voltage ranges from 0.6V to V • Two Step-Down Converters: 600mA Output Current per Converter V
IN Range: 2.7V to 5.5V 1.4MHz Switching Frequency Low R
DS(ON) 0.4 Integrated Power Switches Internal Soft Start 27A Quiescent Current per Converter• Highly Integrated Battery Charger: Programmable Charging Current from 100mA to 1A Pass Device Reverse Blocking Diodes Current Sensing Resistor Digital Thermal Regulation• Short-Circuit, Over-Temperature, and Current Limit Protection• QFN44-24 Package • -40°C to +85°C Temperature Range

Applications

IN . Each converter is capable of delivering up to 600mA of load current.The AAT2550 is available in a Pb-free, space-saving, thermally-enhanced QFN44-24 package and is rated over the -40°C to +85°C temperature range. • Cellular Telephones • Digital Cameras• Handheld Instruments• MP3, Portable Music, and Portable Media Players • PDAs and Handheld Computers

Typical Application

Battery Pack Adapter Serial Interface ADP BATTSCT Batt+

AAT2550

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