High-efficiency step-down DC-DC converter is targeted for operation from 3.3V input voltage. It is able to supply circuits with programmable output voltage 1.8V at 0.7A output current. The DC-DC converter contains overvoltage protection, and undervoltage-lockout circuit. During startup time DC-DC converter can operate both in the soft start mode, which provides the gradual increase of the output voltage and without it. The embedded Bias and LDO blocks provide a required voltage and current references to DC-DC sub-blocks.