Step-down converter will interest designers of a wide variety of portable systems

Most mid- to high-end handsets available today incorporate I2C, so they can easily take advantage of the power efficiencies of voltage scaling. More cost-sensitive handsets, however, simply cannot afford the hardware and firmware overhead associated with implementing I2C. Through its S2Cwire interface, the AAT1142 gives designers the ability to bring the power savings of voltage scaling to virtually any portable system.

The AAT1142 provides dynamic voltage management in programmable steps from as low as 0.6V up to 2.0V with 50mV resolution. The converter delivers up to 800mA output current over a wide 2.7V to 5.5V input range with up to 93 percent efficiency.

Designed to optimise power efficiency across the full load range, the AAT1142 features a multi-function MODE/SYNC pin that allows the user to maintain constant frequency and low noise across the operating range or synchronize the converter to an external clock.

Dynamic voltage management allows a host system to quickly adjust the AAT1142 output voltage on-the-fly to track microprocessor idle-active states, thereby providing high power to the processor only when needed, and saving precious battery life.

Operating at a 2MHz switching frequency, the AAT1142 reduces system footprint by supporting the use of a very small, space-saving external inductor and capacitors.
Over-temperature and short-circuit protection circuits safeguard both the device and system components from potential damage. The converter also features internal soft start and 100 percent duty cycle low-dropout operation.

The AAT1142 is available now in a Pb-free, 3x3mm, low-profile, 12-pin TDFN package or a Pb-free, 12-pin TSOPJW package. The device is specified over the -40 to +85 degrees C operating temperature range.