Skyworks Solutions, Inc. High Efficiency 1X/1.5X/2X Charge Pump for White LED Applications AAT3151

Please note: this product is being discontinued and is not recommended for new designs. The AAT3151 is a low noise, constant frequency charge pump DC/DC converter that uses a tri-mode load switch (1X), fractional (1.5X), and doubling (2X) conversion to maximize efficiency for white LED applications. The AAT3151 is capable of driving four white LEDs at a total of 120mA from a 2.7V to 5.5V input. The current sinks may be operated individually or in parallel for driving higher-current LEDs. A low external parts count (two 1μF flying capacitors and two small 1μF capacitors at VIN and VOUT) makes the AAT3151 ideally suited for small battery-powered applications. AnalogicTech’s AS2Cwire™ (Advanced Simple Serial Control™) serial digital input is used to enable, disable, and set current for each LED with a 16-level logarithmic scale plus four low-current settings down to 50μA for optimized efficiency, with a low housekeeping current ofonly 50μA. The charge pump output of the AAT3151 is equipped with built-in protection for VOUT. Each current sink input has short circuit and auto-disable to guard against LED failure conditions. Built-in soft-start circuitry prevents excessive inrush current during start-up. A low-current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1μA. The AAT3151 is available in a Pb-free, space-saving, thermally-enhanced, 12-pin 3x3mm TDFN package, or in the lower-profile STDFN package. Please note: AAT3151 is not recommended for new designs.