2N3906: Overview,parameter,Main uses,Features,application fields,working principle and alternative models


2N3906 Transistor Detailed Introduction:


The 2N3906 is a commonly used PNP bipolar junction transistor (BJT) that is typically employed for amplification and switching purposes in electronic circuits.



  • Collector Current (Ic): Maximum current flow through the collector.
  • Collector-Base Voltage (Vcbo): Maximum voltage between collector and base.
  • Collector-Emitter Voltage (Vceo): Maximum voltage between collector and emitter.
  • DC Current Gain (hFE): Transistor gain under specific conditions.
  • Power Dissipation (Pd): Maximum power handling capability.
  • DataSheet

    2N3906 PDF

Main Uses:

  • Amplification: Boosting signal strength in audio and RF circuits.
  • Switching: Controlling higher current/voltage loads with a low-power signal.
  • Electronic Control: Driving small motors, relays, and LEDs.
  • Voltage Regulation: Stabilizing voltages in various circuits.


  • Cost-Effective: Widely available at low cost.
  • Small Form Factor: Typically comes in a compact TO-92 package.
  • Moderate Power Handling: Suitable for low to moderate power applications.
  • Versatile: Used in various electronic applications.
  • Easy to Implement: Commonly used in educational electronics projects.

Application Fields:

  • Audio Amplification: Preamplifiers, audio signal processing.
  • Switching Circuits: Low-power switching applications.
  • Voltage Regulation: Linear voltage regulators.
  • Signal Processing: Various types of signal conditioning.

Working Principle:

  • Biasing: Applying proper voltages to the base terminal to control the transistor.
  • Amplification: Small current flowing from base to emitter controls a larger current flow from collector to emitter.
  • Switching: Transitioning the transistor between on (conductive) and off (non-conductive) states.
  • Current Control: Regulating currents based on base current variations.

Alternative Models:

  • 2N4403: Complementary PNP transistor to the 2N3906.
  • BC557: Commonly used PNP transistor with similar characteristics.
  • 2N5088: Another PNP transistor option suitable for similar applications.

The 2N3906 transistor is a fundamental component in electronic circuits, especially for amplification and switching purposes. Alternative models like the 2N4403 and BC557 offer similar functionality and can be used based on specific design requirements. Each alternative transistor may have distinct characteristics and specifications that make them suitable for different applications. For detailed technical information, always refer to the datasheets provided by the transistor manufacturers.