2N3904 TO-92 is a widely used, general-purpose NPN bipolar junction transistor (BJT) designed for low-power, low-voltage, and moderate-speed amplification and switching applications. It comes in a plastic TO-92 package, handling up to 200mA of collector current and 40V, making it a staple in electronics for, among others, signal processing and prototyping.
Specification
Type: NPN Silicon Epitaxial Planar Transistor
Package: TO-92 (plastic)
Max Collector-Emitter Voltage(VCEO): 40V
Max Collector Current(IC): 200mA (0.2A)
Power Dissipation (PD): 625mW
DC Current Gain (hFE): 100 to 300
Transition Frequency (fT): 300MHz
Applications
Switching: Used in circuits to switch small loads.
Amplification: Ideal for audio and low-frequency signal amplification.
General Purpose: Common in hobbyist projects, sensor circuits, and electronic repairs.