250 V / 17 A N-channel — automotive-qualified, DPAK
The STD18NF25: It carries AEC-Q101 qualification, making it a fit for automotive power-train, DC-DC converter, and motor-drive circuits where the junction temperature can reach 175 °C.
At 17 A the conduction loss is I²R = 17² × 0.165 ≈ 48 W under the worst-case Rds(on) — the 110 W power-dissipation rating at the case gives headroom, but the junction-to-case thermal path in the DPAK requires a copper pour on the drain tab to keep Tj below 175 °C. Gate charge is 29.5 nC at 10 V, which means a gate-driver sourcing 1 A can charge the gate in roughly 30 ns — fast enough for a 100 kHz switching regulator without excessive cross-conduction.
AEC-Q101 — the automotive gate
The Automotive grade and AEC-Q101 qualification are the defining differentiators. This part is not just a general-purpose 250 V MOSFET in a DPAK — it has been through the AEC-Q101 stress tests (high-temperature reverse bias, temperature cycling, humidity) that an under-hood or chassis-domain ECU requires. Lifecycle status is Active per STMicroelectronics.