Infineon has marked the BCR148WE6327BTSA1 as Obsolete. No official Infineon successor order code is listed, so pin-compatible substitution requires a cross-reference search against the BCR148 base number.
What it is — pre-biased NPN in a tiny package
The BCR148WE6327BTSA1 is a pre-biased NPN transistor from Infineon, integrating two 47 kOhm resistors — one in series with the base (R1) and one between the emitter and base (R2). This built-in bias network eliminates two external resistors from the board, saving placement cost and PCB area. It is housed in a surface-mount SC-70 (SOT-323) package, specifically the PG-SOT323 variant, and rated for a maximum power dissipation of 250 mW.
Key ratings — 100 mA, 50 V, 100 MHz
Collector current is rated at 100 mA maximum, with a collector-emitter breakdown voltage of 50 V. The transition frequency (fT) is 100 MHz, making it suitable for switching applications up to low-MHz ranges. DC current gain (hFE) is minimum 70 at 5 mA collector current and 5 V Vce. Vce saturation is 300 mV maximum at 500 µA base current and 10 mA collector current. Collector cutoff current is just 100 nA (ICBO), useful for low-leakage designs.
Where it fits — switching and driver circuits
This pre-biased transistor is a natural fit for low-side switching, relay and solenoid drivers, and logic-level interface circuits where you want to drive a load from a microcontroller GPIO without adding external resistors. The SC-70 package suits space-constrained designs like sensor modules, portable devices, and IoT edge nodes.