SO-8 power switch for 30V rails
The IRF7403TRPBF: It comes in the industry-standard 8-SOIC package (0.154" wide, 3.90mm body width), which means the PCB footprint matches countless existing layouts for low-to-medium power switching. With a maximum Rds(on) of 22 milliohms at 4A with 10V gate drive, the conduction loss at rated current stays under 1.6W — within the 2.5W power dissipation limit at 25°C ambient. The 57 nC total gate charge at 10V tells the drive circuit what it needs to push into the gate each cycle; at 100 kHz switching, that's 5.7 mA average gate drive current, easily handled by a standard gate driver IC.
Switching performance and thermal budget
Input capacitance Ciss is 1200 pF at 25V Vds — this sets the Miller plateau charge time and therefore the switching losses. The 4.5V minimum drive voltage means it can be turned on from a 5V logic rail, though the 10V drive yields the lowest on-resistance. Gate threshold voltage is 1V max at 250µA, so the device is fully enhanced well before the gate reaches 4.5V. The operating junction temperature range spans -55°C to 150°C, covering industrial and some automotive under-hood environments. The 2.5W power dissipation at 25°C ambient is specified for the SO-8 on a standard FR4 board — real thermal performance depends on copper area on the drain pads. For continuous 8.5A operation, the PCB must sink the heat; a layout with thermal vias under the SO-8 body is recommended.
Active production, ROHS3 compliant
The base product number is IRF7403, and the TRPBF suffix indicates tape-and-reel packaging with lead-free (RoHS) plating.