Design of fully integrated resonance switched capacitor converters in FDSOI technology

Abstract

The integration of power supplies has the potential to reduce the form factor and cost of electronic systems. The resonance switched capacitor (ReSC) converters show a promising performance as it overcomes the charge-sharing losses in switched capacitor (SC) converters. However, the used inductors need an additional manufacture process. This paper investigates the design of ReSC using an integrated air-core inductors in 28 nm FDSOI technology. Different interleaved topologies are discussed using inductance around 1 nH. The flying and bypass capacitors are implemented using MOM capacitors on-chip. With an inductor quality factor around 6-8 and 1 mm 2 silicon, the ReSC converter shows 30 % lower losses with respect to the SC converter at power density of 0.1 W/mm 2. Although the integrated inductor has a relatively poor quality factor, the fully integrated ReSC converters improve the efficiency of the SC converters. It can be seamlessly implemented in the pre-existing technologies.