Hiccup Mode Overcurrent Protection Scheme for Decentralized Multiphase Current Mode DC-DC Converters

This paper proposes a robust hiccup mode over current protection scheme for decentralized current mode multiphase DC-DC converters. The current comparator for pulse width modulation is reused for peak current limiting. The latch-up issue in multiphase configuration, which is caused by the inevitable current limit thresholds mismatching between the paralleled controllers is analyzed. Without adding extra communication bus to the system, the proposed scheme synchronizes the hiccup protection using the existing shared signals between controllers. The proposed scheme features precise cycle-by-cycle instantaneous current limit, low power dissipation under fault condition, simple implementation and scalability in phase number. The proposed scheme is implemented in an integrated circuit controller for dual phase Boost converter. The experimental results prove the effectiveness of the proposed scheme.