What this PROFET switch does in a power distribution design
The Infineon BTS550PE3146HKSA1 is a single-channel high-side power switch from the PROFET® family, designed to replace a discrete MOSFET plus driver and protection circuitry in 12 V and 24 V automotive and industrial loads. It integrates a vertical N-channel power MOSFET with charge pump, current sensing, and a full set of fault protections — current limiting, open load detection, over-temperature shutdown, and over-voltage clamp — so the load sees a clean on/off command from a logic-level input without external clamp diodes or current-sense resistors.
The typical 2.8 mOhm on-resistance is the standout parametric here. At a 10 A continuous load, conduction loss is just 0.28 W — low enough that the TO-218-5 package can dissipate it without a heatsink in still air at 25°C ambient, provided the PCB copper area under the tab is adequate. The 90 A maximum output rating is a pulsed peak; the real continuous current is set by the junction temperature budget, the load voltage, and the thermal resistance of the mounting interface.
Infineon has marked the BTS550PE3146HKSA1 as obsolete. No last-time-buy window remains; procurement should plan for a one-time buy or a form-fit-function replacement qualification.
Load voltage range and application fit
The switch handles a 5 V to 34 V load supply, covering automotive 12 V (nominal 13.5 V, load-dump to 34 V), truck 24 V systems, and industrial 24 V PLC buses. The through-hole TO-218-5 package (also known as TO-218AB/5) provides a large copper tab for heatsink attachment, making it a practical choice for high-current retrofit or repair applications where a surface-mount D²PAK would need a thicker PCB.
Fault protection set — what is covered
Four integrated fault protections reduce external component count: fixed current limiting prevents the switch from exceeding a safe current level during a short circuit; open load detection flags a disconnected harness or blown fuse; over-temperature shutdown protects the die if the heatsink is undersized; and over-voltage clamping absorbs load-dump transients up to the 34 V load supply maximum. The input is non-inverting — a logic high turns the output on — and no external Vcc supply is needed; the charge pump runs from the load voltage.