MMST5551 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 160 V
• Collector-Base Voltage, max: 180 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 0.2 A
• Collector Dissipation: 0.2 W
• DC Current Gain (h_fe): 80 to 250
• Transition Frequency, min: 300 MHz
• Noise Figure, max: 8 dB
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: SOT-323
• Electrically Similar to the Popular 2N5551 transistor

Here is an image showing the pin diagram of this transistor.The MMST5551 transistor is marked as "K4N".The complementary PNP transistor to the MMST5551 is the MMST5401.The 2N5551 is the TO-92 version of the MMST5551.