What this HEXFET does in the circuit
The Infineon AUIRF1405-INF is an automotive-qualified N-channel HEXFET power MOSFET in a TO-220AB through-hole package. It is designed for high-current switching in 12 V and 24 V automotive systems—motor drives, DC-DC converters, battery isolation, and solenoid drivers—where its 55 V drain-source breakdown and 75 A continuous drain rating provide the headroom for transient-rich environments like engine bays and chassis-mounted controllers.
5.3 mOhm Rds(on) — what it means for conduction losses
At 75 A continuous, the I²R loss is under 30 W, which the 330 W package dissipation ceiling handles with a properly heatsinked TO-220. The gate charge of 260 nC at 10 V means the gate driver must deliver a 2.6 µC pulse to switch the device; a standard automotive gate-driver IC with 2 A peak source will turn it on in roughly 130 ns.
Automotive temperature grade and construction
The HEXFET stripe-cell architecture keeps the Rds(on) positive-temperature-coefficient characteristic, which helps parallel operation and prevents thermal runaway at high current. The TO-220AB package is a standard through-hole power package, compatible with existing heatsink clips and PCB layouts for 75 A-class designs.
Lifecycle and sourcing posture
No last-time-buy or phase-out risk is indicated for this order code.