MPS3904 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: 0.1 A
• Collector Dissipation: 0.625 W
• DC Current Gain (h_fe): 100 to 300
• Transition Frequency, min: 300 MHz
• Noise Figure, max: 5 dB
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92

The MPS3904 is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, base, and collector leads.
Here is an image showing the pin diagram of this transistor.The 2SC1623 (SOT-23), KSC1623 (SOT-23) and PMBS3904 (SOT-23) is the SMD version of the MPS3904 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the MPS3904 with the 2N3904, 2N4401, 2SC1008, 2SC1210, 2SC1211, 2SC815, BC537, BC538, HS945, KN2222A, KN3904, KSC1008, KSC815, KSC945, KSP05, KSP06, KSP2222A, KSP8098, KSP8099, KTC9014, KTC9014B, KTN2222A, MPS2222A, MPS2222AG, MPS650, MPS650G, MPS651, MPS651G, MPS8098, MPS8098G, MPS8099, MPS8099G, MPSA05, MPSA05G, MPSA06, MPSA06G, MPSW01A, MPSW01AG, MPSW05, MPSW05G, MPSW06, MPSW06G, NTE123AP, P2N2222A, P2N2222AG, PN100, PN2219A, PN2222A, PN2484, PN3569, PN4033, S9014, S9014B, SS9014, SS9014B or ZTX450.