What this pre-biased NPN does on your board
The Infineon BCR112E6327HTSA1 is an NPN pre-biased transistor in a PG-SOT23 surface-mount package. It integrates two 4.7 kOhm resistors — one in series with the base (R1) and one between base and emitter (R2) — so you can drive it directly from a logic output or microcontroller GPIO without adding external bias components. This saves two resistors per transistor and shrinks the placement footprint to a single three-pin SOT-23.
Key ratings for the design decision
Collector current is rated 100 mA maximum, with a collector-emitter breakdown voltage of 50 V. The 140 MHz transition frequency means it handles switching up into the low-MHz range — fine for relay drivers, LED switching, or level translation at typical logic speeds. Saturation voltage is 300 mV at 500 µA base drive and 10 mA collector current, so it stays cool in low-drop applications. The integrated resistor divider sets a fixed base current ratio; the minimum DC current gain of 20 at 5 mA, 5 V tells you the forced beta is roughly 10, which guarantees hard saturation when the input is high. Collector cutoff leakage is 100 nA maximum, negligible for most loads.
Lifecycle status — last buy window
This part carries a Last Buy lifecycle status. Infineon has announced end-of-life and is accepting final orders through a defined last-time-buy window.