The ROHM EMX18T2R is a dual NPN transistor in a tiny SOT-563 / SOT-666 package, rated for 12V collector-emitter breakdown and 500mA continuous collector current. With a 320MHz transition frequency and a minimum DC current gain of 270 at 10mA, it handles fast switching and logic-level drive without breaking a sweat. The 150mW power dissipation limit and 150°C junction temperature rating mean it can sit in warm environments — think LED lighting modules, portable audio amplifiers, or the secondary-side drive of a small DC-DC converter. The dual NPN configuration saves board space compared to two discrete SOT-23s, which matters when you're cramming a BOM into a 10mm PCB edge.
500mA collector current and 12V breakdown — sizing the load
The 500mA Ic max and 12V Vceo set the operating window. The 250mV saturation voltage at 200mA base drive keeps conduction losses low.
Package and footprint — SOT-563 / EMT6 reality
The EMX18T2R ships in a SOT-563 or SOT-666 case (the supplier device package is EMT6). That's a 1.6mm x 1.6mm body with six leads — two collectors, two bases, two emitters — so the footprint is about half the area of a single SOT-23. The datasheet's recommended land pattern calls for 0.5mm pad pitch and 0.3mm pad width. Hand-soldering is possible with fine tweezers and a small iron tip, but reflow is the production path. MSL is typically 1 for this package class, but verify the reel label — no bake needed unless the bag is breached.
Lifecycle and compliance — active and ROHS3
The ROHS3 compliance covers the full substance restriction list, including the four phthalates — no exemption paperwork needed for EU-market products.