特点
Dynamically Adjustable Output from 0.3V to 3.5V
600mA Output Current
Internal 0.08 Ohm P-Channel MOSFET Bypass Transistor
High Efficiency: Up to 96%
1.5MHz Constant Frequency Operation
No Schottky Diode Required
Low Dropout Operation: 100% Duty Cycle
2.5V to 5V Input Voltage Range
Shutdown Mode Draws <1μA Supply Current
Current Mode Operation for Excellent Line and Load Transient Response
Overtemperature Protected
Available in 8-Lead 3mm x 3mm DFN Package
典型应用

典型应用

描述
The LTC?3408 is a high efficiency monolithic synchronous buck regulator optimized for WCDMA power amplifier applications. The output voltage can be dynamically programmed from 0.3V to 3.5V. At V OUT > 3.6V an internal 0.08? bypass P-channel MOSFET connects V OUT directly to V IN , eliminating power loss through the inductor.
The input voltage range is 2.5V to 5V making the LTC3408 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems.
Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode.
The LTC3408 is available in a low profile (0.75mm) 8-lead 3mm × 3mm DFN package.
U.S. Patent Numbers: 5481178, 6580258, 6304066, 6127815, 6498466, 6611131