Micrel has a 2.5MHz dual 800mA synchronous buck regulator with a switching architecture which is designed for light load efficiency in Li-Ion battery powered systems.

The step-down regulator offers an input voltage range from 2.5 to 5.5V and a quiescent current of 28[micro]A at light loads.

The regulator’s design offers two modes of operation, a variable frequency Trickle Mode operation for highest light load efficiency with an automatic switchover into full load, and an option for running the device at a constant frequency. 

The device will also offer a power good output signal for sequencing capability.  The MIC2238 is available in a 12-pin 3x3mm package with a junction operating range from -40 to +125 deg C.