30 mOhm Rds(on) — the conduction loss floor for a 9 A load
The BTS432E2E3043 is a single-channel high-side power switch from Infineon's PROFET® family, designed to replace a relay or discrete MOSFET in 12 V and 24 V automotive loads. The 30 mOhm typical on-resistance sets the conduction loss at 9 A continuous output — about 2.4 W dissipation at full load, which the TO-220-5 package sinks to the board or a heatsink. The 4.5 V to 42 V load supply range covers nominal 12 V car electrical systems and 24 V truck/bus systems without a separate gate-drive supply (Vcc/Vdd not required).
Fault protection suite — what the original design relied on
This part integrates fixed current limiting, open-load detection, over-temperature shutdown, and over-voltage clamping — the full protection set that makes a PROFET a self-protecting smart switch rather than a bare MOSFET. The auto-restart feature means the switch re-enables after a fault clears, which is useful for lamp or motor loads that draw inrush current. The status flag output (open-drain) feeds a microcontroller GPIO for diagnostic readback.
Obsolete — sourcing through independent distribution
Infineon lists the BTS432E2E3043 as obsolete. A buyer planning a new design should evaluate Infineon's current PROFET portfolio for a form-fit-function replacement; the TO-220-5 footprint and 30 mOhm Rds(on) class narrow the search.