The MP9403 is a monolithic synchronous buck regulator. The device integrates a 150mΩ high side MOSFET and a 100mΩ low side MOSFET that provides 3A continuous load current over input voltage of 4.3V to 7V. Current mode control provides fast transient response and cycle-by-cycle current limit. An adjustable soft-start prevents inrush current at turn-on. In shutdown mode, the supply current drops to 1μA. This device, available in an 8-pin SOIC package with exposed pad, provides a very compact system solution with minimal reliance on external components.