Dual NPN with integrated bias — what it saves on the board
The ROHM EMG3T2R packs two NPN transistors each with a 4.7kΩ base resistor built into a single SC-75 package. That means one component replaces two discrete transistors plus two resistors, cutting placement cost and board area on low-side driver and logic-level switching circuits. The 250 MHz transition frequency keeps it useful for modest-speed switching up into the low MHz range.
150 mW total — thermal budget in a tiny package
At 150 mW total power dissipation for both transistors, this is a small-signal part, not a power switch. The SC-75 case has minimal copper area to sink heat; keep the sum of both channels under the 150 mW ceiling at 25°C ambient and derate above that. For a typical 5 mA load with 0.15 V VCE(sat), each transistor dissipates under 1 mW, so there is plenty of headroom for logic-level interface and signal gating.
Saturation voltage and gain — what to expect at 5 mA
VCE(sat) is specified at 150 mV maximum with 250 µA base drive into 5 mA collector current.