40 V N-Channel HEXFET® — what the ratings mean for your switching design
The AUIRFS8403TRL is an Infineon N-Channel HEXFET® power MOSFET rated for a 40 V drain-source breakdown and a continuous drain current of 123 A. The low on-resistance of 3.3 mOhm (max) at 70 A and 10 V gate drive keeps conduction losses down in high-current switching stages — think DC-DC converters, motor drives, and battery management in automotive or industrial power trains. The total gate charge of 93 nC at 10 V is moderate for a device this size; your gate driver needs to source that charge fast enough to keep switching edges clean, especially if you are pushing frequency above 100 kHz.
Temperature range and environment
Rated for junction temperatures from -55°C to 175°C, this MOSFET is built for under-hood automotive and high-ambient industrial enclosures.
Sourcing and lifecycle
That means no last-time-buy pressure and no forced redesign for the foreseeable future. For a BOM freeze or a new design-in, this part is a clean choice from a supply perspective.