AAT3155 Datasheet | AAT

Description The AAT3155 is a low noise, constant frequency charge pump DC/DC converter that uses a trimode load switch (1X), fractional (1.5X), and doubling (2X) conversion to maximize efficiency for white LED applications. The AAT3155 is capable of driving up to four channels of LEDs at 20m A per channel 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 IN and OUTCP) make this part ideally suited for small, battery-powered applications. Analogic Tech's S2Cwire™ (Simple Serial Control™) serial digital input is used to enable, disable, and set current for each LED with 16 settings down to 50μA. The low-current mode supply current can be as low as 50μA to save power. Each output of the AAT3155 is equipped with builtin protection for output short-circuit and auto-disable for load short-circuit conditions. Built-in softstart circuitry prevents excessive inrush current during start-up. A low-current shutdown feature disconnects the load from the input and reduces quiescent current to less than 1μA. The AAT3155 is available in a Pb-free, space-saving 2.85x3.0mm 12-pin TSOPJW package. Features - - - - - - - - - - - - Charge Pump™ VIN Range: 2.7V to 5.5V Fully Programmable Current with Single Wire - 16 Current Levels - Four Low Current Settings Down to 50µA Low IQ (50µA) for Low Current Mode Tri-Mode 1X, 1.5X, and 2X Charge Pump for Maximum Efficiency and VF Coverage Drives up to Four Channels of LEDs No Inductors, Low Noise Operation 1MHz Constant Switching Frequency Small Application Circuit Built-In Thermal Protection Automatic Soft Start IQ <1µA in Shutdown 2.85x3.0mm TSOPJW-12 Package Applications - - - - Color (RGB) Lighting Programmable Current Sinks White LED Backlighting White Photo Flash for Digital Still Cameras Typical Application C1+ C1 1µF C2+ C2 1µF C12.7V to 5.5V CIN 1µF C2OUTCP COUT...