The MIC4684 is a high-efficiency 200kHz stepdown (buck) switching regulator. Power conversion efficiency of above 85% is easily obtainable for a wide variety of applications. The MIC4684 achieves 2A of continuous current in an 8-lead SO (small outline) package at 60°C ambient temperature. High efficiency is maintained over a wide output current range by utilizing a boost capacitor to increase the voltage available to saturate the internal power switch. As a result of this high efficiency, no external heat sink is required. The MIC4684, housed in an SO-8, can replace larger TO-220 and TO-263 packages in many applications. The MIC4684 allows for a high degree of safety. It has a wide input voltage range of 4V to 30V (34V transient), allowing it to be used in applications where input voltage transients may be present. Built-in safety features include over-current protection, frequency-foldback short-circuit protection, and thermal shutdown. The MIC4684 is available in an 8-lead SO package with a junction temperature range of -40°C to +125°C.