Pre-biased NPN in a tiny leadless package
The BCR 101L3 E6327: The Infineon BCR 101L3 is an NPN pre-biased transistor with two 100 kOhm resistors integrated into the same die. Rated for 50 V collector-emitter breakdown and 50 mA continuous collector current, with a 250 mW power dissipation ceiling. The 100 MHz transition frequency is fine for low-speed switching up to a few megahertz — think GPIO-driven loads, small relays, or level translation. The part comes in a SC-101 / SOT-883 package, which Infineon calls PG-TSLP-3-4. That is a three-pin leadless package.
Matched 100 kOhm resistors — one less BOM line
The integrated base resistor (R1) and base-emitter resistor (R2) are both 100 kOhms. Vce saturation is 300 mV at 250 µA base drive and 5 mA collector current. The DC current gain is specified at 70 minimum at 5 mA collector current and 5 V Vce — typical for a pre-biased part where the gain is deliberately held moderate to guarantee saturation. Vce saturation is 300 mV maximum at 250 µA base drive and 5 mA collector current, which is adequate for driving a 5 V relay coil or an LED string. Collector cutoff current is 100 nA maximum — low enough that it will not leak through a MOSFET gate pull-down or a high-impedance logic input in the off state.
Active lifecycle — no LTB panic
No last-time-buy notice, no end-of-life flag. For the sourcing desk, that means it is still a standard-production line from Infineon, not a scavenger-hunt part.