What the 270 mOhm Rds(on) means for your load budget
The Infineon BTS308 E3062A is a single-channel PROFET high-side power switch rated for continuous loads up to 1.18 A. The 270 mOhm typical on-resistance at 25°C sets the conduction loss floor — at 1 A that's 270 mW dissipated in the die, which drives the junction temperature rise above the 150°C absolute maximum. If your load is a lamp inrush or a motor start, the current limit (fixed, non-programmable) clamps the peak before the die sees a short.
Load voltage range and supply rail fit
The 4.7 V to 34 V load voltage range covers 12 V and 24 V nominal systems with enough headroom for load-dump transients up to 40 V class. No external Vcc supply is needed — the switch is self-powered from the load pin, which simplifies the BOM for a simple on/off relay-replacement or solenoid driver.
Fault protection set — what is and is not included
Missing from the list: reverse-battery protection and short-to-ground latch-off — the auto-restart feature means the switch cycles back on after a fault clears, which is fine for a resettable load but not for a safety-critical path that needs a latched off state.
The TO-263-5 (D²Pak) package has a large exposed copper tab on the bottom. For continuous 1.18 A at 85°C ambient, budget at least 2 square inches of 2-oz copper on the bottom layer to keep TJ below 150°C.
No official second-source or pin-compatible cross-reference is published for this exact variant.