Dual pre-biased transistor in a single SOT-363
The Toshiba RN4989(T5L,F,T) integrates one NPN and one PNP pre-biased transistor in a single 6-pin SOT-363 (US6) surface-mount package. Each transistor includes built-in bias resistors — 47 kΩ base (R1) and 22 kΩ emitter-base (R2) — eliminating the need for external resistor pairs in low-current switching and interface circuits. Collector-emitter breakdown is rated at 50 V, with a maximum collector current of 100 mA per transistor and total package dissipation of 200 mW.
Saturation and gain at typical drive
Vce(sat) is specified at 300 mV maximum with 250 µA base current driving 5 mA collector current — a common condition for logic-level interface and relay pre-drive. Transition frequency is 250 MHz for the NPN side and 200 MHz for the PNP, adequate for low-speed PWM and digital signal inversion up to a few megahertz.