NPN pre-biased transistor with integrated bias network
The Infineon BCR135WE6327 is an NPN pre-biased transistor — a digital transistor that integrates the bias resistors directly into the package. It includes a 10 kOhm base resistor (R1) and a 47 kOhm emitter-base resistor (R2), eliminating two external components per transistor from the board. Rated for a maximum collector current of 100 mA and a collector-emitter breakdown voltage of 50 V, it suits low-current switching and interface applications where board space is tight.
Switching performance and power handling
Transition frequency is 150 MHz, adequate for typical switching speeds in digital input interfaces, relay drivers, and level shifters. The 250 mW power dissipation limit in the SC-70 package means the device is sized for signal-level loads rather than continuous high-current drive. Vce saturation is 300 mV maximum at 500 µA base current and 10 mA collector current — the on-state voltage drop is low enough to keep the transistor cool in saturated switching.
Package and mounting
Housed in the SC-70 (SOT-323) package, the supplier device package is PG-SOT323-3-1. Surface-mount assembly with a compact footprint — three leads, no exposed pad. The small body suits dense PCB layouts where every square millimetre counts.