NCV8405AonsemiAutomotive low-side gate driver · SOT-223NCV8405A is an onsemi AEC-Q101 self-protected low-side driver — an integrated N-channel power switch with built-in current limit, thermal shutdown and voltage clamping, for driving relays, solenoids, lamps and heaters in automotive and industrial loads from a logic-level signal. The integration is the selection point: one 3-pin device replaces a discrete MOSFET plus sense resistor, clamp diode and protection circuitry, and it reports fault state back through its gate-input current (distinct current-limit and thermal-limit fault signatures), so the host MCU can detect a faulted load without extra sense wiring. Key ratings: 42 V internally clamped drain-to-source voltage, 90 mΩ typical on-resistance at VGS = 10 V (105 mΩ typical at 5 V), current limit about 9 A typical at VGS = 5 V and 10.5 A typical at 10 V (25°C), thermal turn-off about 180°C typical at 5 V with 15°C hysteresis, 275 mJ single-pulse avalanche energy, 53 V load-dump capability, and -40°C to +150°C junction temperature. Selection advice: the A suffix is the ordering variant available in SOT-223 (STT1G/STT3G) and DPAK (ADTRKG) — pick SOT-223 for compact layouts and DPAK where higher dissipation (about 2.0–2.5 W versus 1.0–1.7 W) is needed. Drive it at 10 V where the lowest on-resistance matters; 5 V logic drive works but runs hotter at the same current. Do not substitute the B suffix: its only ordering code (DPAK) is discontinued. Featured on Mouser New Products (2026-10-15). Parameters verified against onsemi documentation. State quantity, packing and date-code requirements in your RFQ; we reconfirm the offered lot before quotation and reply within 24 hours.