The TD1484B is a monolithic synchronous buck regulator.  The  device  integrates  two  90m? MOSFETs, and provides 3A of continuous load current over a wide input voltage of 4.75V to 23V.   Current    mode        control provides fast transient response and cycle-by-cycle current limit.

An adjustable soft-start prevents inrush current at turn-on, and in shutdown mode the supply current drops to 1μA. The TD1484B regulates the output voltage in automatic PSM/PWM mode operation, depending on the outputcurrent, for high efficiency operation over light to full load current.

This  device, available in an SOP8-PP package, provides a very compact solution with minimal external components. 

Features
* 3A Output Current
* Wide 4.75V to 23V Operating Input Range
* Integrated 90m? Power MOSFET Switches
* Output Adjustable from 0.923V to 20V
* Up to 93% Efficiency
* Pulse Save Mode(PSM)/PWM Mode Operation
* Programmable Soft-Start
* Stable with Low ESR Ceramic Output Capacitors
* Fixed 340KHz Frequency
* Cycle-by-Cycle Over Current Protection
* Input Under Voltage Lockout

Applications
* Distributed Power Systems
* Networking Systems
* FPGA, DSP, ASIC Power Supplies
* Green Electronics/ Appliances
* Notebook Computers