As network data rates climb and mobile products such as smart phones add a dizzying array of complex applications, transient response becomes a major obstacle to high performance. By combining an architecture specifically tuned for fast transient response with a high switching frequency, AnalogicTech’s AAT1130 high performance step-down converter allows designers to both support rising performance requirements and reduce solution size by using compact, low profile inductors. The AAT1130 is a 500mA monolithic step-down converter. Using an innovative pseudo fixed-frequency architecture, the converter offers transient response at least 2X faster than a traditional 500mA, 2MHz, PWM-mode buck converter while supporting the use of extremely small, 1microH chip-scale inductors.
Designed for mobile electronics applications, the converter operates across a 2.7V to 5.5V input range and low quiescent current of 60microA and delivers an output between 0.6V and 1.8V. The AAT1130 delivers up to 500mA of maximum continuous output current. Internal MOSFET switches allow the converter to support efficiency rates up to 92% over a wide load range. The AAT1130’s architecture operates at a fixed switching frequency in steady-state operation while allowing the control circuit to react almost instantly to transients. With a programmed output voltage of 1.2V, the AAT1130 can handle severe load transients from 10mA to 500mA and still maintain output voltage accuracy within +/- 5%. Operating at a high 2.5MHz switching frequency, the step-down converter keeps output voltage ripple low while enabling the use of small, 1mm high 0603 inductors. The device is available with either fixed or adjustable output regulation voltage options.
In the adjustable configuration, output voltage is set with an external resistor voltage divider circuit. To manage output voltage overshoot, the AAT1130 features internal soft start. The IC also includes over-temperature and current limit protection circuits. The AAT1130 is qualified across the -40 to +85 degrees C temperature range. It comes in a 2 x 2.2mm,10-pin SC70JW package.
