50 V, 100 mA NPN pre-biased — built-in resistors save board space
It integrates a 22 kΩ base resistor (R1) and a 47 kΩ emitter-base resistor (R2), eliminating two discrete passives from the BOM and shrinking the layout. Collector-emitter breakdown is rated at 50 V, continuous collector current at 100 mA, and transition frequency at 150 MHz — a general-purpose switching transistor for low-power loads up to 200 mW.
Infineon has placed the BCR142E6327HTSA1 into Last Buy status, meaning final production orders are being accepted for a limited window. After that, the part will be discontinued. For new designs or long-running production, identify a pin-compatible pre-biased NPN in the same SOT-23 footprint with matching resistor values — several Infineon BCR series parts share the pinout. For existing BOMs, the surplus and broker channel remains the supply path once the LTB window closes.
The 22 kΩ base resistor sets the turn-on threshold: with a 5 V logic signal, base current sits around (5 V − 0.7 V) / 22 kΩ ≈ 195 µA, enough to saturate the transistor with Ic up to 10 mA. The 47 kΩ emitter-base resistor provides a hard pull-down when the drive is off, keeping leakage below 100 nA. Vce(sat) is 300 mV at 500 µA base drive and 10 mA collector current — low enough for logic-level switching without excessive dissipation. The 150 MHz fT means it handles PWM into the low-MHz range cleanly.