Power loss analysis of dynamic threshold SOI power MOSFET used in a synchronized DC-DC converter

摘要

The power loss of dynamic threshold (DT) SOI power MOSFET and conventional SOI power MOSFET were compared. The on-resistance of DT 801 power MOSFET was about 10% lower and the gate-charge of it was about 5% higher than those of the conventional SOI device. These results demonstrate that the DT SOI power MOSFET is more suitable for large current and low voltage applications than conventional SOI device. From our analysis, we estimated that the power loss of DT SOI device as the synchronized rectification device was 9% lower than that of the conventional SOI device at a switching frequency of 1 MHz and root-mean-square current of 500 mA.