HEXFET N-channel for high-current switching
The Infineon AUIRF2903Z is a 30 V, 160 A N-channel HEXFET MOSFET in a TO-220AB through-hole package, designed for low on-resistance switching in power conversion and motor drive circuits. Rds(on) is specified at 2.4 mOhm maximum with a 75 A drain current and 10 V gate drive — this is the conduction loss figure that sets the thermal budget for the heatsink. The 240 nC total gate charge at 10 V sets the gate drive current requirement for the target switching frequency.
Thermal and environment envelope
The 290 W power dissipation rating is the absolute maximum under ideal heatsinking; real-world continuous dissipation depends on the heatsink thermal resistance and airflow, so size the heatsink for the actual switching losses.
Gate drive and threshold
Gate threshold voltage is 4 V maximum at 250 µA drain current — this is the turn-on edge; a 10 V gate drive is recommended to fully enhance the channel and achieve the rated Rds(on). Maximum gate-source voltage is ±20 V.