Triple boundary multiphase with predictive interleaving technique for switched capacitor DC-DC converter regulation

Abstract

In this paper, we propose a new technique to regulate multi-phase interleaved switched-capacitor DC-DC converters. Traditionally, SC converters are either regulated by modulating the switching frequencies directly through a voltage-controlled-oscillator or by using hysteretic control where separate control loops are used for each converter core. Achieving fast regulation by modulating VCO is difficult because it requires a high speed error amplifier and proper loop compensation. Conventional hysteretic controller achieves fast regulation, but it uses N comparators or one shared comparator that operates at N times the single phase switching frequency, where N is the level of interleaving. The proposed technique avoids these problems by using triple boundary hysteretic control, where one comparator is used for defining the reference voltage, and the other two comparators enable coarse/fine operation to achieve both fast recovery and tight regulation.