A novel step-up VRM — Two-phase interleaved coupled-boost converter

摘要

Two-phase boost converter operates at a very large duty cycle due to a high output voltage and a low input voltage. Using coupled-boost topology can extend duty cycle, but it has a huge spike across MOSFET voltage due to leakage energy. This paper proposes an active clamping scheme of the two-phase interleaved coupled-boost converter that the power switches have two functions: they serve as the control switches for their own channels and meanwhile, also serve as the active clamping switches for neighbor channels, and only adding a capacitor can realize active clamping function. Both analysis and experiment have shown that it has good effect for restraining spike voltage in a two-phase coupled-boost converter.