The Micrel MIC23051 is a high efficiency 600mA PWM synchronous buck (step-down) regulator featuring HyperLight Load™, a patented switching scheme that offers best in class light load efficiency and transient performance while providing very small external components and low output ripple at all loads. The MIC23051 has an output voltage scaling feature that can toggles between two different voltage levels. The MIC23051 also has a very low typical quiescent current draw of 20µA and can achieve over 85% efficiency even at 1mA. The device allows operation with a tiny inductor ranging from 0.47µH to 2.2µH and uses a small output capacitor that enables a sub-1mm height solution. In contrast to traditional light load schemes HyperLight Load™ architecture does not need to trade off control speed to obtain low standby currents and in doing so the device only needs a small output capacitor to absorb the load transient as the powered device goes from light load to full load. At higher loads the MIC23051 provides a constant switching frequency of greater than 4MHz while providing peak efficiencies greater than 93%. The MIC23051 is available in fixed output voltage options from 0.72V to 3.3V eliminating external feedback components. The MIC23051 is available in an 8-pin 2mm x 2mm MLF® with a junction operating range from –40°C to +125°C.