50 V / 150 mA PNP in SC-70 — signal-path switching and amplification
The 2SA1586-Y,LF is a general-purpose PNP epitaxial transistor from Toshiba, rated for 50 V collector-emitter breakdown and 150 mA continuous collector current. With a 100 mW power dissipation limit in the SC-70 (SOT-323) package, it is sized for low-power signal conditioning, relay or LED drivers, and level translation on mixed-voltage boards. The Y-grade gain bin guarantees a DC current gain (hFE) of 120 minimum at 2 mA collector current and 6 Vce — tight enough for matched-pair audio preamp stages or bias networks where beta consistency matters more than raw current capability.
Maximum Vce saturation is 300 mV at 10 mA base drive and 100 mA collector current. That means the collector-emitter drop stays under 0.3 V when the transistor is fully on — efficient enough to drive a 100 mA relay coil from a 5 V rail without a heatsink, as long as the average power stays within the 100 mW package limit. Collector cutoff current is 100 nA maximum (ICBO) — the off-state leakage is low enough for battery-powered circuits that spend most of their time in sleep mode, where every microamp counts.
Standard lead times apply through authorized distribution; no LTB or allocation signal at this point in the cycle. ROHS3 compliant — no exemptions expiring, no substance restrictions for EU or global markets. The SC-70 package is lead-free compatible with standard reflow profiles (MSL level not stated, but typical for this package is MSL1).
SC-70 footprint and board integration
The 3-pin SC-70 (SOT-323) package measures 2.0 mm × 1.25 mm with a 0.65 mm pin pitch. The collector is on pin 2 (the center tab), which also serves as the primary thermal path — the copper pad under the package on the PCB should connect to a ground plane or a wide trace to keep junction temperature within the 125°C max rating. Available in Tape & Reel (standard 3000-piece reel) or Cut Tape for prototype runs — the same die and package regardless of reel configuration, so qualification on one format transfers to the other.