5.7 mOhm at 15 A — the conduction loss number
The IRFR3711ZTRPBF is an Infineon HEXFET N-channel MOSFET in a D-Pak (TO-252-3) surface-mount package. Its headline rating is a maximum on-resistance of 5.7 mOhm at 15 A drain current with 10 V gate drive — that is the figure that sets the conduction loss and the copper area you need on the PCB to keep the junction below 175 °C.
20 V rail — tight headroom, low Rds(on) payoff
With a 20 V drain-to-source rating, this part is built for low-voltage rails — 12 V input converters, point-of-load regulators, and battery-management switches where the extra 5 mOhm from a 30 V part would burn efficiency. Gate charge is 27 nC at 4.5 V — the 4.5 V drive voltage matches the logic-level threshold of many gate drivers and MCU PWM outputs, so you can switch at moderate frequencies without a separate driver stage. The 2160 pF input capacitance at 10 V Vds helps size the drive impedance for the rise-time budget.
175 °C junction — under-hood and industrial ambient
The operating junction temperature range spans -55 to 175 °C. That places it in the class of parts used in engine-control modules, transmission controllers, and industrial drives.