A 1 MHz Boost DC-DC Converter with Turn on ZCS Capability to Reduce EMI

Abstract

This paper proposes a boost DC-DC converter with turn-on zero current switching (ZCS) capability to suppress electromagnetic interference (EMI) generated from an output diode. When a switching component turn on, reverse current flows from the output diode. In SiC-SBD, reverse recovery time is very short and conduction loss is small, but noise is increased by switching speed over MHz. By operating in discontinuous current mode, noise at turn-on can be reduced. However, at high frequency over MHz, the conduction loss increases because peak current flowing through the switching component and inductor increases. Radiated EMI of the boost DC-DC converter is reduced by the ZCS soft switching at turn on operating in the continuous current mode. Measurement results of EMI of the ZCS DC-DC converter were presented to confirm EMI suppression from the ZCS operation.