Pre-biased NPN — what the built-in resistors buy you
It integrates a 22 kΩ base resistor (R1) and a 47 kΩ emitter-base resistor (R2), eliminating two external passives from the board — a space and placement-cost win for high-volume switching loads like relay drivers, LED indicators, and logic-level interface circuits. DC current gain minimum is 70 at 5 mA, 5 V, and collector cutoff current is just 100 nA, so off-state leakage won't load a CMOS output or pull down a bias rail.
Infineon lists the BCR142B6327HTLA1 as Obsolete. No last-time-buy window remains open through the factory channel. Because the pre-biased resistor network is the distinguishing feature, a direct replacement must match the 22 kΩ / 47 kΩ divider ratio and the PG-SOT23 footprint. The BCR142 family shares the same base part number; other suffix variants may carry different resistor values or package options — verify the full order code before substituting.
