Advanced Analogic Technologies (AnalogicTech) has developed the AAT2556, a multi-function SystemPower IC that combines a battery charger and a step-down converter in one package. The device is suited for single-cell Li-Ion/Polymer battery-based ultraportable systems, such as Bluetooth headsets, handheld GPS devices, and high-end portable music players.
The step-down converter in the AAT2556 delivers up to 250 mA of output current. It operates in both fixed and variable frequency modes to support high-efficiency levels that range up to 96%. No-load quiescent current is 30 μA. A 1.5-MHz switching frequency minimizes the size of external components and keeps switching losses low.
The battery charger is a complete constant current/constant voltage (CCCV) linear charger. Designed to operate from USB or ac adapter inputs across a 4.0- to 6.5-V input range, it integrates a charging device and reverse blocking diode to regulate battery charge voltage and current for single-cell lithium-ion/polymer batteries. Charging current is programmable from 15 to 500 mA using an external resistor.
To ensure device integrity, the AAT2556 adds over-voltage, over-current, and thermal protection circuits. It's immediately now in a 3- by 3-mm, 12-pin, Pb-free, TDFN package. It sells for $1.68 each in 1000-piece quantities. For more information, visit AnalogicTech's Web site at www.analogictech.com.