800 V, 6 A — the offline power switch in DPAK
The STD7N80K5: This voltage-current combination targets the primary-side switch in offline flyback converters, PFC boost stages, and auxiliary power supplies.
1.2 Ohm Rds(on) and 13.4 nC gate charge — conduction vs. switching trade-off
Maximum on-resistance is 1.2 Ohm at 3 A drain current with 10 V gate drive — the Rds(on) at the rated 6 A will be higher due to self-heating, so the designer should budget conduction loss using the typical Rds(on) vs. temperature curve from the datasheet. The 13.4 nC total gate charge at 10 V is low enough that many PWM controllers with 1 A peak drive capability can switch this FET at 65–100 kHz without an external driver stage. Input capacitance Ciss is 360 pF at 100 V Vds, which keeps the switching node capacitance manageable and reduces the turn-on energy loss in hard-switched topologies.