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 20mA 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 1F flying capacitors and two small 1F capacitors at IN and OUTCP) make this part ideally suited for small, battery-powered applications.