DESCRIPTION
The LTC®3409A is a high efficiency, monolithic synchronous buck regulator using a constant frequency, current mode architecture. The LTC3409A improves upon the LTC3409’s light load regulation in Burst Mode operation. The output voltage is adjusted via an external resistor divider.

FEATURES
■ 1.6V to 5.5V Input Voltage Range
■ 0.62V to 5.5V Output Voltage Range
■ Internal Soft-Start
■ Selectable 1.7MHz or 2.6MHz Constant Frequency
   Operation
■ Internal Oscillator Can Be Synchronized to an
   External Clock, 1MHz to 3MHz Range
■ High Efficiency: Up to 95%
■ 65μA Quiescent Current, Burst Mode® Operation
■ 600mA Output Current (VIN = 1.8V, VOUT = 1.2V)
■ 750mA Peak Inductor Current
■ No Schottky Diode Required
■ Low Dropout Operation: 100% Duty Cycle
■ 0.612V Reference Voltage
■ Stable with Ceramic Capacitors
■ Shutdown Mode Draws <1μA Supply Current
■ Current Mode Operation for Excellent Line and Load
   Transient Response
■ Overtemperature Protection
■ Available in a Low Profile (0.75mm)
   8-Lead (3mm × 3mm) DFN Package

APPLICATIONS
■ Cellular Phones
■ Digital Cameras
■ MP3 Players