7 Summary

The need to control ringing produced by the switching of power semiconductors has existed in industry as long as semiconductor devices have been used in switching mode power supplies. It is interesting to note that the boot resistor affects only the turn-on speed of the high-side FET, making this method an efficient approach to reduce ringing with a small impact on the total solution efficiency. Using this boot resistor method significantly reduces the noise in the entire system, which can be a good trade-off.

RBOOT does not reduce the frequency of the switch node ringing which can be needed to address EMI issues. In situations where additional switch-node ring control is required, a snubber can be added to reduce both the amplitude and the ring frequency found on SW node.