Dual NPN pre-biased transistor — R1=R2=10kΩ, 150mW, SOT-563
The ROHM EMH61T2R packs two NPN pre-biased transistors into a single SOT-563 package (also designated EMT6), each with 10kΩ base and 10kΩ emitter-base resistors integrated on-chip. This is the part you reach for when a board needs a couple of low-current digital switches — relay drivers, level shifters, or logic inverters — and you want to cut the resistor count from four passives to one tiny six-pin device. Collector current is rated 50mA max, collector-emitter breakdown at 50V, and the transition frequency hits 250MHz, so it handles modest-speed switching cleanly. Maximum power dissipation is 150mW for the whole package — that's the thermal ceiling for the SOT-563 footprint, so keep the total current through both transistors within that budget.
The 150mW max power rating is the hard limit for this tiny SOT-563 package. At 50V VCE, 5mA collector current per transistor (10mA total) you're already at 500mW if both transistors are saturated — that's over three times the package limit. In practice, this part is for signal-level loads: driving a few milliamps into an LED, switching a relay coil via a transistor buffer, or pulling a logic line low. If you need to switch more than about 10mA continuous per channel, step up to a larger package like SOT-23 or SOT-323. The 150mV saturation voltage at 500µA base, 5mA collector is tight — good for low-drop switching.
ROHS3 compliant.