DESCRIPTION
The LTC®1503-1.8/LTC1503-2 are switched capacitor step-down DC/DC converters that produce a regulated output from a 2.4V to 6V input. The parts use switched capacitor fractional conversion to achieve high efficiency over the entire input range. No inductors are required. Internal circuitry controls the step-down conversion ratio to optimize efficiency as the input voltage and load conditions vary. Typical efficiency is 25% higher than that of a low dropout (LDO) linear regulator.

FEATURES
■ Input Voltage Range: 2.4V to 6V
■ Fixed Output Voltages: 1.8V ±4%, 2V ±4%
■ Output Current: Up to 100mA
■ No Inductors
■ Typical Efficiency 25% Higher than LDOs
■ Low Operating Current: 25µA
■ Low Shutdown Current: 5µA
■ 600kHz Switching Frequency
■ Shutdown Disconnects Load from VIN
■ Soft-Start Limits Inrush Current at Turn-On
■ Short-Circuit and Overtemperature Protected
■ Available in 8-Pin MSOP and SO Packages

APPLICATIONS
■ Cellular Phones
■ Handheld Computers
■ Smart Card Readers
■ Low Power DSP Supplies
■ Portable Electronic Equipment
■ Handheld Medical Instruments