12.2 mOhm Rds(on) — the conduction-loss floor for a 40 V dual switch
The Infineon IPG20N04S412AATMA1 is a dual N-channel MOSFET from the OptiMOS™ family, rated 40 V drain-to-source and 20 A continuous drain at 25°C. Its on-resistance is specified at 12.2 mOhm maximum with a 17 A drain current and 10 V gate drive — that is the conduction-loss floor for a 40 V dual switch in a PG-TDSON-8-10 package. AEC-Q101 qualification and a 175°C junction temperature rating place it in automotive under-hood and chassis-domain applications where both reliability and thermal headroom are non-negotiable.
The PG-TDSON-8-10 package includes a wettable flank, which means the side pads accept solder and are visible to automated optical inspection after reflow. For automotive production lines that require AOI coverage on every joint, this eliminates the need for X-ray inspection on hidden solder fillets.
Gate charge and input capacitance — the driver budget
Maximum gate charge is 18 nC at 10 V, and input capacitance is 1470 pF at 25 V drain-to-source. A 100 kHz switching frequency with 18 nC gate charge draws 1.8 mA from the gate driver per channel — well within the capability of a standard automotive gate-driver IC. The 1470 pF Ciss means the driver sees a moderate capacitive load; no special high-current driver is needed for the target switching speed.