2A step-down converter meets portable system rising power needs
(Technology News, 25 Apr 2008 )
Advanced Analogic Technologies has announced the AAT1153, a 1.2 MHz constant frequency, current mode step-down converter capable of delivering up to 2A of output current. Available in a compact, 3x3-mm TDFN package, this new highly efficient synchronous device helps portable system designers meet rising power requirements and still deliver a small, power-efficient solution.
The AAT1153 supplies up to 2A output current from a 2.5V to 5.5V input. Output voltage can range from 0.6V to VIN. Current mode operation offers excellent line and load transient response.
The new step-down converter extends battery life by running at efficiency levels as high as 95% and can achieve 90% efficiency at its full rated 2A load. It also uses low RDS(ON) internal switches which can run at 100% duty-cycle for low-dropout operation. In addition, light load operation minimizes output ripple for noise sensitive applications.
Using a high 1.2 MHz constant switching frequency, the AAT1153 allows designers to use small external components including lower cost ceramic capacitors. The internal slope compensation setting helps minimize system footprint by allowing the designer to use smaller inductor values. . The AAT1153 offers both short-circuit and over-temperature protection. Soft start circuitry limits current surge at input and eliminates output voltage overshoot. It also offers a low shutdown current of < 1 µA.
