STN851 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 150 V
• Emitter-Base Voltage, max: 7 V
• Collector Current − Continuous, max: 5 A
• Collector Dissipation: 1.6 W
• DC Current Gain (h_fe): 150 to 350
• Transition Frequency, min: 130 MHz
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: SOT-223

Here is an image showing the pin diagram of this transistor.The STN851 transistor is marked as "N851".The complementary PNP transistor to the STN851 is the STN951.You can replace the STN851 with the NZT44H8.