High-Efficiency CMOS Buck Converter with Wide Output Voltage Range

This paper presents an integrated DC-DC buck converter with variable output voltage (from 1.2 V up to 5 V) and capability for delivering a wide range of output currents. The converter is optimized for achieving high efficiency, which is in range from 88% to 94.4% for output voltages from 1.2 V to 3.1V and output currents from 0.4 A to 1.2 A. Also, an overview of the converter losses is given, especially considering the losses caused by the high-side (HS) and low-side (LS) switching transistors.