MMST4401 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 40 V
• Collector-Base Voltage, max: 60 V
• Emitter-Base Voltage, max: 6 V
• Collector Current − Continuous, max: 0.6 A
• Collector Dissipation: 0.2 W
• DC Current Gain (h_fe): 100 to 300
• Transition Frequency, min: 250 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: SOT-323
• Electrically Similar to the Popular 2N4401 transistor

Here is an image showing the pin diagram of this transistor.The MMST4401 transistor is marked as "K3X".The complementary PNP transistor to the MMST4401 is the MMST4403.The 2N4401 is the TO-92 version of the MMST4401.You can replace the MMST4401 with the FJX2222A, KTN2222AU, MMST2222A or PMST4401.