On-resistance and gate drive — what the numbers mean
The IRF7424TRPBF: Rds(on) is specified at 13.5 mOhm max with 11 A drain current and 10 V gate-source. For a 12 V battery-ORing design running at 5 A, the conduction loss at 10 V drive is under 0.4 W, well within the 2.5 W power dissipation limit at 25°C ambient. Gate charge is 110 nC at 10 V. This part is suited to DC or low-frequency switching.
Package and mounting
The 8-SOIC package has a 0.154-inch width. The copper pad on the PCB under the body is the primary heat path. Operating junction temperature range is -55°C to 150°C. The 2.5 W power dissipation at 25°C ambient assumes a standard board with minimal copper.
