DESCRIPTION
The LTC®3564 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. Supply current during operation is only 20μA, dropping to ≤1μA in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3564 ideally suited for single Li-Ion battery-powered or 3.3V to 5V input voltage 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 runtime.

FEATURES
■ High Efficiency: Up to 96%
■ Very Low Quiescent Current: Only 20μA
■ 1.25A Output Current
■ 2.5V to 5.5V Input Voltage Range
■ 2.25MHz 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 and
   6-Lead (2mm × 3mm) DFN Packages

APPLICATIONS
■ Cellular Telephones
■ Wireless and DSL Modems
■ Digital Still Cameras
■ Media Players
■ Portable Instruments
■ Point of Load Regulation