P-Channel high-side switch for 12V/24V automotive loads
The Infineon AUIRFR5305TRL is a P-Channel enhancement-mode MOSFET from the Automotive HEXFET® series, qualified to AEC-Q101 for stress reliability. It is designed for high-side switching in automotive and industrial applications where a positive supply rail must be switched without a charge-pump or bootstrap circuit — a P-Channel simplifies the gate drive by referencing to ground. The 55V drain-source rating (Vdss) provides headroom for 12V and 24V systems with load-dump transients, while the 31A continuous drain current (Id) at 25°C case temperature covers motor, solenoid, and DC-DC converter loads. The 65 mOhm maximum on-resistance at 16A, 10V gate drive keeps conduction losses manageable in a DPAK footprint.
Gate drive and switching performance
The gate threshold voltage (Vgs(th)) is 4V maximum at 250 µA drain current, meaning the device is fully off below that threshold and requires a gate drive of 10V to achieve the rated 65 mOhm Rds(on). The maximum gate-source voltage rating is ±20V, so the gate driver must not exceed that absolute maximum — a 12V gate drive is well within the window. The total gate charge (Qg) is 63 nC at 10V, which translates to moderate switching losses at frequencies up to a few tens of kHz; for higher-frequency PWM, the input capacitance of 1200 pF at 25V Vds should be factored into the gate-driver sizing.
Temperature range and thermal management
The junction temperature range spans -55°C to 175°C, covering automotive under-hood, engine bay, and military-grade environments. The maximum power dissipation is 110W at case temperature (Tc), but that figure assumes an ideal heatsink; in a real DPAK layout on a standard FR4 board, derating is significant. For a 31A continuous load, the case must be kept below 175°C, which typically requires a copper area on the PCB or an external heatsink. The 175°C TJ max is the absolute limit — nominal operation should stay well below that to avoid accelerated aging.
Package and mounting
The AUIRFR5305TRL is supplied in a TO-252-3 (DPak) surface-mount package, also known as SC-63, with the supplier device code PG-TO252-3. The tab is the drain terminal, so the PCB copper pour connected to the tab serves as both the drain node and the primary thermal path. Cut Tape (CT) quantities are also available for prototyping or low-volume builds.
Lifecycle and compliance
The AUIRFR5305TRL is listed as Active in production — no last-time-buy or obsolescence risk at this time. It is ROHS3 compliant, meeting the current EU restriction of hazardous substances directive.