Pre-biased NPN with integrated bias resistors — 50 V, 100 mA
The Infineon BCR135E6359HTMA1 is an NPN pre-biased transistor in the SOT-23-3 package, built with two integrated bias resistors — R1 of 10 kΩ between base and input, and R2 of 47 kΩ from base to emitter. This internal resistor network eliminates two external passives from the BOM, saving board space and reducing pick-and-place cost in high-volume automotive assemblies. Rated for a collector-emitter breakdown voltage of 50 V and a continuous collector current of 100 mA, the part handles typical low-side switching and digital interface loads found in automotive ECUs, body controllers, and sensor modules. The 150 MHz transition frequency keeps switching edges clean for logic-level signals up to a few megahertz.
Automotive qualification and temperature range
The part is listed as Last Buy per the lifecycle record. Buyers should plan for a final procurement window; once the last-time-buy closes, the only channel will be surplus or broker stock.
Bias resistor values and switching behaviour
The built-in R1 of 10 kΩ and R2 of 47 kΩ set the base drive and the off-state leakage path. With a minimum DC current gain (hFE) of 70 at Ic=5 mA, Vce=5 V, the transistor saturates with a Vce(sat) of 300 mV at Ib=500 µA, Ic=10 mA — a typical drive level for a logic output or a small relay coil. The collector cutoff current is specified at 100 nA maximum (ICBO), which keeps the off-state leakage negligible in battery-powered or low-quiescent automotive modules. The 200 mW power dissipation limit in the SOT-23-3 package means the part is suited for signal-level switching rather than continuous high-current loads.