DESCRIPTION
The LTC®3619B is a dual monolithic synchronous buck regulator using a constant frequency current mode architecture.
The input supply voltage range is 2.5V to 5.5V, making it ideal for Li-Ion and USB powered applications. 100% duty cycle capability provides low dropout operation, extending the run time in battery-operated systems. Low output voltages are supported with the 0.6V feedback reference voltage. Channel 1 and channel 2 can supply 400mA and 800mA output current, respectively.

FEATURES
■ Programmable Average Input Current Limit:
   ±5% Accuracy
■ Dual Step-Down Outputs: Up to 96% Efficiency
■ Low Noise Pulse-Skipping Operation at Light Loads
■ Input Voltage Range: 2.5V to 5.5V
■ Output Voltage Range: 0.6V to 5V
■ 2.25MHz Constant-Frequency Operation
■ Power Good Output Voltage Monitor for Each Channel
■ Low Dropout Operation: 100% Duty Cycle
■ Independent Internal Soft-Start for Each Channel
■ Current Mode Operation for Excellent Line and Load
   Transient Response
■ ±2% Output Voltage Accuracy
■ Short-Circuit Protected
■ Shutdown Current ≤ 1μA
■ Available in Small Thermally Enhanced 10-Lead MS
   and 3mm × 3mm DFN Packages

APPLICATIONS
■ High Peak Load Current Applications
■ USB Powered Devices
■ Supercapacitor Charging
■ Radio Transmitters and Other Handheld Devices