AAT3175 Datasheet PDF - Analog Technology Inc

General Description
The AAT3175 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 flash applications. The AAT3175 is capable of driving up to three flash LEDs at 300mA total current from a 2.7V to 5.5V input. A low external parts count (two 1µF flying capacitors and two small 1µF capacitors at VIN and VOUT) make this part ideally suited for small battery-powered applications.

FEATUREs
• VIN Range: 2.7V to 5.5V
• Up to 300mA Total Flash Current
• Fully Programmable Current with Single Wire
    — 16 Logarithmic Current Levels
• Tri-Mode 1X, 1.5X, and 2X Charge Pump for Maximum Efficiency and VF Coverage
• Drives 3-in-1 or 2-in-1 Flash LEDs
    — 0.5% Current Matching
• No Inductors, Low Noise Operation
• 1MHz Constant Switching Frequency
• Small Application Circuit
• Built-In Thermal Protection
• Automatic Soft-Start
• IQ <1µA in Shutdown
• TDFN33-12 Package

APPLICATIONs
• Programmable Current Sinks
• White LED Backlighting
• White Photo Flash for Mobile Phones