AAT3129_07

High Efficiency 1X/1.5X/2X Charge Pump for RGB Color LED Applications General Description The AAT3129 is a high efficiency charge pump DC/DC converter with tri-mode load switch (1X) fractional (1.5X) and doubling (2X) conversion for color LED applications. A single current source output provides a regulated current to drive R, G, and B LEDs via three internal switches. With a simple single wire serial bus, the RGB module can be easily controlled to display 4096 colors. AnalogicTech's Advanced Simple Serial Control™ (AS2Cwire™) serial digital input is used to enable, disable, and set the duty cycle of each internal MOSFET switch. Low external parts count (two 1μF flying capacitors and two small bypass capacitors at VIN and OUT) makes the AAT3129 ideally suited for small battery-powered applications. The AAT3129 has a thermal management system to protect the device in the event of a short-circuit condition on any of the output pins. Built-in softstart circuitry prevents excessive inrush current during start-up. High switching frequency enables the use of small external capacitors. A low current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1μA. The AAT3129 is available in a Pb-free, 12-pin TSOPJW package. AAT3129 Features • • • • • • • • • • • • ChargePump™ VIN Range: 2.7V to 5.5V Common Anode RGB LED Control 4096 Color with Single Wire Digital Control 40mA to 180mA Fixed Current Source AS2Cwire Digital Brightness Control Low Noise Constant Frequency Operation Small Application Circuit Regulated Output Current No Inductors 1MHz Switching Frequency IQ