Complementary NPN/PNP pair in a single SC-74 package
The Infineon BC817UPNB6327XT integrates an NPN and a PNP bipolar transistor in one SC-74 (SOT-457) surface-mount package, saving board space compared to two separate SOT-23 devices. With a collector-emitter breakdown voltage of 45 V and a maximum collector current of 500 mA per transistor, it suits low-to-moderate power switching, signal amplification, and push-pull driver stages in industrial control, power management, and general-purpose analog circuits.
45 V breakdown, 500 mA collector current, 330 mW power budget
Each transistor inside the package is rated for a 45 V Vce breakdown and 500 mA continuous collector current, with a total package power dissipation of 330 mW. The 700 mV Vce(sat) at 500 mA collector current gives a reasonable saturation voltage for a general-purpose switching transistor — expect about 350 mW conduction loss at full current in saturation. The 170 MHz transition frequency means usable gain into the low-MHz range for linear or switching applications.
hFE minimum 160 at 100 mA — consistent gain for complementary stages
The DC current gain is specified at a minimum of 160 when measured at 100 mA collector current and 1 V Vce. This guarantees a predictable base-drive requirement for both the NPN and PNP halves, which is useful when matching gain in a push-pull output or a current-mirror topology. The 100 nA maximum collector cutoff current keeps leakage negligible at room temperature, though it will increase with junction temperature — the 150 °C junction rating sets the thermal limit.
SC-74 / SOT-457 — small footprint for dense layouts
The part comes in an SC-74 (SOT-457) package with six leads, identified by the supplier as PG-SC74-6. This is a surface-mount package roughly 2.9 mm × 1.6 mm, suitable for automated assembly on standard FR-4 boards.