P-channel load switch in an 8-SOIC — the 20V, 6.7A IRF7404TRPBF
The IRF7404TRPBF is a P-Channel MOSFET from Infineon's HEXFET series, rated for a drain-to-source voltage of 20 V and a continuous drain current of 6.7 A at 25°C. It comes in an 8-SOIC surface-mount package, making it a fit for automated assembly on boards where a P-channel device is needed for high-side switching without a charge pump.
Switching performance — the numbers that matter for gate drive and loss budget
The Rds(on) is specified at 40 mOhm maximum at a gate drive of 4.5 V and 3.2 A drain current. That is the on-resistance you design your conduction losses around at the typical logic-level gate voltage. Gate charge Qg is 50 nC at 4.5 V Vgs, and input capacitance Ciss is 1500 pF at 15 V Vds. These set the switching speed and the drive current required from the gate driver — a 50 nC gate at 100 kHz draws 5 mA average from the driver, well within the SOA of a standard logic gate or dedicated driver. The gate threshold voltage is specified as a maximum of 700 mV at 250 µA drain current, with a minimum of 1.0 V implied by the 700 mV max at that low current.
Thermal and environmental limits — operating range and power dissipation
Maximum power dissipation is 2.5 W at 25°C ambient, derated to zero at 150°C junction. In an 8-SOIC with standard copper land area, the thermal resistance RthJA is around 50°C/W — the 2.5 W figure is achievable with good board-level heat sinking.