Why the built-in bias resistors save board space
The Infineon BCR108SH6327 packs two NPN pre-biased transistors into a single PG-SOT363-6-1 package, each with a 2.2kΩ base resistor (R1) and a 47kΩ base-emitter resistor (R2). That means you drop the external resistor pair per channel — two parts gone from the BOM. Rated for 50V collector-emitter breakdown and 100mA continuous collector current, it handles typical automotive loads like relay drivers, solenoid pre-drives, and logic-level interface buffers without extra passives.
This part carries Automotive AEC-Q101 qualification, so it's released for the stress profiles and reliability targets that tier-one ECU programs require. The 170MHz transition frequency is fast enough for PWM drive up through the low-MHz range, and the 300mV Vce saturation at 500µA base / 10mA collector keeps conduction losses low in switched loads. Off-state leakage is trimmed to 100nA max (ICBO), which matters when the transistor sits on a shared bus line in a module that sleeps.