A 50-MHz Fully Integrated Low-Swing Buck Converter Using Packaging Inductors

Abstract

Implementation of on-chip passive elements and efficient regulation schemes are key aspects of fully integrated dc-dc converter design. This paper presents a 50-MHz fully integrated buck converter equipped with packaging inductors. These inductors include parasitic inductances of the bonding wires and lead frames in the package. They have significantly better Q factors than the best on-chip inductors implemented on silicon. This paper also presents full-swing and low-swing gate drivers for efficient regulation of high-frequency switching converters. The low-swing driver uses the drop voltage of a diode-connected transistor and is applied in a fabricated converter to reduce the gate driving loss caused by the high switching operation. The proposed converter is designed and fabricated using a 0.13-mu m 1-poly 6-metal CMOS process. The fully integrated buck converter achieves 68.7% and 76.8% efficiency for 3.3 V/2.0 V and 2.5 V/1.8 V conversions, respectively, while providing a load current of 250 mA.