LTC3419 Datasheet | Linear Technology

Features n High Efficiency Dual Step-Down Outputs: Up to 96% n 600m A Current per Channel at VIN = 3V n Only 35μA Quiescent Current During Operation (Both Channels) n 2.25MHz Constant-Frequency Operation n 2.5V to 5.5V Input Voltage Range n Low Dropout Operation: 100% Duty Cycle n No Schottky Diodes Required n Internally pensated for All Ceramic Capacitors n Independent Internal Soft-Start for Each Channel n Available in Fixed Output Versions n Current Mode Operation for Excellent Line and Load Transient Response n 0.6V Reference Allows Low Output Voltages n User-Selectable Burst Mode® Operation n Short-Circuit Protected n Ultralow Shutdown Current: IQ < 1μA n Available in Small MSOP or 3mm × 3mm DFN-8 Packages APPLICATIONS n Cellular Telephones n Digital Still Cameras n Wireless and DSL Modems n Portable Media Players n PDAs/Palmtop PCs Dual Monolithic 600m A Synchronous Step-Down Regulator DESCRIPTION The LTC®3419 is a dual, 2.25MHz, constant-frequency, synchronous step-down DC/DC converter in a tiny 3mm × 3mm DFN package. 100% duty cycle provides low dropout operation, extending battery life in portable systems. Low output voltages are supported with the 0.6V feedback reference voltage. Each regulator can supply 600m A output current. The input voltage range is 2.5V to 5.5V, making it ideal for Li-Ion and USB powered applications. Supply current during operation is only 35μA and drops to <1μA in shutdown. A user-selectable mode input allows the user to trade off between high efficiency Burst Mode operation and pulse-skipping mode. An internally set 2.25MHz switching frequency allows the use of tiny surface mount inductors and capacitors. Internal soft-start reduces inrush current during start-up. Both outputs are internally pensated to work with ceramic output capacitors. The LTC3419 is available in a low profile (0.75mm) 3mm × 3mm DFN package. The LTC3419 is also available in a fixed output voltage configuration selected via internal resistor dividers...