The AAT3166 is a low noise, constant frequencycharge pump DC/DC converter that uses a trimodeload switch (1X), fractional (1.5X), and doubling(2X) conversion to maximize efficiency forwhite LED applications. The AAT3166 is capable ofdriving four LEDs for a total of 108mA from a 2.7Vto 5.5V input. The current sinks may be operatedindividually or in parallel for driving higher-currentLEDs. A low external parts count (two 1μF flyingcapacitors and two small 1μF capacitors at IN andOUTCP) make this part ideally suited for small,battery-powered applications.