General Description
The AAT3141 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 device produces current levels up to 30mA on each of its 4 current source outputs to drive various arrangements of LEDs from a 2.7V to 5.5V input. Outputs 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 CP) make the AAT3141 ideally suited for small battery-powered applications.

FEATUREs
• Tri Mode 1x, 1.5x, and 2x Charge Pump for Maximum Efficiency and VF coverage
• Drives Low-VF & High-VF Type LEDs
• Up to 4, 30mA Outputs
• AS2Cwire Independent 3+1 output addressing
• 32 Position Logarithmic Scale with Digital Control
• Low Noise Constant Frequency Operation
• 1MHz Switching Frequency
• Small Application Circuit
• Regulated Output Current
• Automatic Soft-Start
• VIN Range: 2.7V to 5.5V
• No Inductors
• Iq < 1µA in Shutdown
• 12 pin TSOPJW package

APPLICATIONs
• White LED Backlighting
• White Photo-Flash for DSCs
• Color (RGB) Lighting
• Programmable Current Sources