650 V, 15 A N-channel MDmesh™ II in TO-220FP
The STF20NM65N is a 650 V drain-source, 15 A continuous drain N-channel power MOSFET from STMicroelectronics' MDmesh™ II series. The MDmesh™ II technology reduces on-resistance and gate charge compared to planar MOSFETs of the same voltage class. Gate charge totals 44 nC at 10 V gate-source, which keeps switching losses manageable in hard-switched topologies up to the 100 kHz range. Input capacitance measures 1280 pF at 50 V drain-source bias. This saves assembly time and improves thermal interface reliability. Maximum power dissipation is 30 W at case temperature. Junction temperature rating is 150 °C maximum.
The 650 V drain-source voltage gives headroom for 400 V DC bus rails in power factor correction stages or flyback converters, with derating margin for switching transients. The 15 A continuous rating at 25 °C case temperature derates with case heating; at elevated case temperatures the usable current drops per the datasheet curve. At 270 mOhm maximum on-resistance, conduction loss at 7.5 A is roughly 15 W. For lower-duty or lower-current applications the 270 mOhm figure directly scales the I²R loss. Gate charge of 44 nC at 10 V means a 1 A gate driver charges the gate in about 44 ns, which is fast enough for 100 kHz hard-switching without excessive cross-conduction. Slower gate drive or higher switching frequency may increase switching losses.