DESCRIPTION
The LTC®3406 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in an adjustable version and fixed output voltages of 1.5V and 1.8V. Supply current during operation is only 20µA and drops to ≤1µA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3406 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. Automatic Burst Mode® operation increases efficiency at light loads, further extending battery life.

FEATURES
■ High Efficiency: Up to 96%
■ Very Low Quiescent Current: Only 20µA During Operation
■ 600mA Output Current
■ 2.5V to 5.5V Input Voltage Range
■ 1.5MHz Constant Frequency Operation
■ No Schottky Diode Required
■ Low Dropout Operation: 100% Duty Cycle
■ 0.6V Reference Allows Low Output Voltages
■ Shutdown Mode Draws ≤1µA Supply Current
■ Current Mode Operation for Excellent Line and Load Transient Response
■ Overtemperature Protected
■ Low Profile (1mm) ThinSOTTM Package

APPLICATIONS
■ Cellular Telephones
■ Personal Information Appliances
■ Wireless and DSL Modems
■ Digital Still Cameras
■ MP3 Players
■ Portable Instruments