HV MOSFETs target several-hundred-volt breakdown ranges, typically using super-junction structures to keep on-resistance low even at high voltage, mainly serving AC-DC power supplies, PFC stages and industrial inverter switching. Compared with low-voltage parts, HV MOSFETs need closer attention to how switching loss is split and to reliability when switching off inductive loads.
Reading the Key Parameters
- VDS_Max (drain-source voltage rating): listed parts span roughly 300V~800V. Evaluate against both line-voltage variation and switching spikes, typically keeping generous margin so bus ripple plus spikes don't approach the rating.
- RDS(ON) (on-resistance @VGS=10V, typical): listed parts range roughly 14.5mΩ~1100mΩ typical (up to about 1300mΩ by the max-value spec), with the lowest values on high-current super-junction parts (e.g. SMJ60R017CFY) and the high end on low-current 500V discretes. Conduction resistance spans widely within each package, so selection should go by the specific part's RDS(ON) figure — package mainly governs thermal capability and mechanical footprint, not a fixed correlation with resistance.
- Qg (gate charge): listed parts span roughly 6nC~260nC and, together with RDS(ON), set switching loss; high-frequency topologies such as PFC should weight low Qg to control drive loss and switching time.
- EAS_Max (avalanche energy rating): listed parts span roughly 62mJ~3420mJ, reflecting how much energy the device can absorb when switching off an inductive load — a key reliability spec at high voltage that on-resistance and switching-loss numbers alone don't capture.
- Package: TO247-3L, TO220-3L, TO263-3L and TO252-3L all appear; package thermal resistance directly caps the achievable thermal design in high-voltage, high-power use.
Three Steps to Select
- Size VDS margin against line-voltage variation plus switching spikes;
- Trade off RDS(ON) against Qg based on the topology's switching frequency;
- Confirm EAS covers the actual inductive-load turn-off condition, then match package and thermal design to the power level.
Common Pitfalls
- Selecting the VDS class from steady-state bus voltage alone, without accounting for line transients and switching spikes;
- Ignoring EAS and selecting purely on RDS(ON), leading to reliability issues under inductive loads or abnormal turn-off;
- Carrying low-frequency selection habits into high-frequency topologies — chasing low RDS(ON) alone while overlooking the switching-loss increase from higher Qg.
More parts can be filtered by VDS, RDS(ON), package and other criteria in the online selector; submit a part inquiry for specific fit questions.