AAT3171

High Current, High Efficiency Charge Pump with Auto-Timer General Description The AAT3171 is a high output current, high efficiency, low noise, low profile charge pump DC/DC converter. The device is ideal for multi-functional LED photo-flash applications where solution cost, size, and efficiency are critical. The AAT3171 is capable of driving a regulated output current up to 800mA. Output current levels can be easily programmed in 16 steps through AnalogicTech's Simple Serial Control™ (S2Cwire™) interface controlled by a single microcontroller GPIO line. This allows smooth transitions and flexible adjustment of brightness in flash or other lighting modes. The maximum output current can also be set with an external RSET resistor. The tri-mode (1X/1.5X/2X) operation of the internal charge pump offers excellent power efficiency throughout the output current range for both flash and movie modes. Combined with a low external parts count (two 1µF flying capacitors and two small bypass capacitors at VIN and OUT), the AAT3171 is ideally suited for small battery-powered applications. The AAT3171 has a thermal management system to protect the device in the event of a short-circuit condition at the output pin. Built-in soft-start circuitry prevents excessive inrush current during start-up. The shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1µA. The AAT3171 is available in a Pb-free, thermallyenhanced 12-pin 3x3mm TDFN package and is specified over the -40°C to +85°C temperature range. AAT3171 Features • • • • • • • • • • ChargePump™ Up to 800mA Output Current Tri-Mode 1X/1.5X/2X in Current Mode 16 Current Level Steps Set by S2Cwire External RSET to Set Maximum Current